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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
______________________________________
FORM 10-Q
______________________________________
(Mark One)

☒ | QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended September 30, 2021
OR

☐ | TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from to
Commission file number 0-12508
______________________________________
S&T BANCORP INC.
(Exact name of registrant as specified in its charter)
______________________________________

Pennsylvania |  |  |  | 25-1434426
(State or other jurisdiction of incorporation or organization) |  | (IRS Employer Identification No.)
800 Philadelphia Street | Indiana | PA |  | 15701
(Address of principal executive offices) |  | (zip code)

800-325-2265
(Registrant’s telephone number, including area code)
Not Applicable
(Former name, former address, and former fiscal year, if changed since last report)
Securities registered pursuant to Section 12(b) of the Act:

Title of each class | Trading Symbol(s) | Name of each exchange on which registered
Common Stock, $2.50 par value | STBA | The NASDAQ Stock Market LLC

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐
Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and "emerging growth company" in Rule 12b-2 of the Exchange Act.

Large accelerated filer | ☒ | Accelerated filer | ☐
Non-accelerated filer | ☐ | Smaller reporting company | ☐
|  | Emerging growth company | ☐
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒
APPLICABLE ONLY TO CORPORATE ISSUERS:
Indicate the number of shares outstanding of each of the issuer’s classes of common stock, as of the latest practical date.
Common Stock, $2.50 Par Value - 39,350,383 shares as of October 31, 2021

Table of Contents
S&T BANCORP, INC. AND SUBSIDIARIES
INDEX
S&T BANCORP, INC. AND SUBSIDIARIES

|  | Page No.
PART I. FINANCIAL INFORMATION |
Item 1. | Financial Statements |
| Consolidated Balance Sheets - September 30, 2021 and December 31, 2020 | 2
| Condensed Consolidated Statements of Comprehensive Income (L oss) - Three and Nine Months Ended September 30, 2021 and 2020 | 3
| Consolidated Statements of Changes in Shareholders' Equity - Three and Nine Months Ended September 30, 2021 and 2020 | 4
| Condensed Consolidated Statements of Cash Flows - Three and Nine Months Ended September 30, 2021 and 2020 | 6
| Notes to Consolidated Financial Statements | 7
Item 2. | Management's Discussion and Analysis of Financial Condition and Results of Operations | 38
Item 3. | Quantitative and Qualitative Disclosures About Market Risk | 55
Item 4. | Controls and Procedures | 57
PART II. OTHER INFORMATION |
Item 1. | Legal Proceedings | 57
Item 1A. | Risk Factors | 57
Item 2. | Unregistered Sales of Equity Securities and Use of Proceeds | 58
Item 3. | Defaults Upon Senior Securities | 58
Item 4. | Mine Safety Disclosures | 59
Item 5. | Other Information | 59
Item 6. | Exhibits | 59
| Signatures | 60

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S&T BANCORP, INC. AND SUBSIDIARIES
CONSOLIDATED BALANCE SHEETS
(Unaudited)

| September 30, 2021 |  | December 31, 2020
( in thousands, except share and per share data) | (Unaudited) |  | (Audited)
ASSETS |  |  |  |  |
Cash and due from banks, including interest-bearing deposits of $856,105 and $158,903 at September 30, 2021 and December 31, 2020 |  | $ | 934,377 |  |  |  | $ | 229,666 |
Securities, at fair value |  | 870,121 |  |  |  | 773,693 |
Loans held for sale |  | 4,303 |  |  |  | 18,528 |
Portfolio loans, net of unearned income |  | 6,970,087 |  |  |  | 7,225,860 |
Allowance for credit losses on loans |  | (108,348) |  |  |  | (117,612) |
Portfolio loans, net |  | 6,861,739 |  |  |  | 7,108,248 |
Bank owned life insurance |  | 83,259 |  |  |  | 82,303 |
Premises and equipment, net |  | 52,727 |  |  |  | 55,614 |
Federal Home Loan Bank and other restricted stock, at cost |  | 9,893 |  |  |  | 13,030 |
Goodwill |  | 373,424 |  |  |  | 373,424 |
Other intangible assets, net |  | 7,334 |  |  |  | 8,675 |
Other assets |  | 238,877 |  |  |  | 304,716 |
Total Assets |  | $ | 9,436,054 |  |  |  | $ | 8,967,897 |
LIABILITIES |  |  |  |  |
Deposits: |  |  |  |  |
Noninterest-bearing demand |  | $ | 2,652,314 |  |  |  | $ | 2,261,994 |
Interest-bearing demand |  | 971,321 |  |  |  | 864,510 |
Money market |  | 2,045,320 |  |  |  | 1,937,063 |
Savings |  | 1,074,896 |  |  |  | 969,508 |
Certificates of deposit |  | 1,201,268 |  |  |  | 1,387,463 |
Total Deposits |  | 7,945,119 |  |  |  | 7,420,538 |
Securities sold under repurchase agreements |  | 72,586 |  |  |  | 65,163 |
Short-term borrowings |  | — |  |  |  | 75,000 |
Long-term borrowings |  | 22,693 |  |  |  | 23,681 |
Junior subordinated debt securities |  | 64,128 |  |  |  | 64,083 |
Other liabilities |  | 129,847 |  |  |  | 164,721 |
Total Liabilities |  | 8,234,373 |  |  |  | 7,813,186 |
SHAREHOLDERS’ EQUITY |  |  |  |  |
Common stock ($2.50 par value) Authorized—50,000,000 shares Issued—41,449,444 shares at September 30, 2021 and December 31, 2020 Outstanding—39,367,847 shares at September 30, 2021 and 39,298,007 shares at December 31, 2020 |  | 103,623 |  |  |  | 103,623 |
Additional paid-in capital |  | 403,028 |  |  |  | 400,668 |
Retained earnings |  | 762,374 |  |  |  | 710,061 |
Accumulated other comprehensive (loss) income |  | (1,029) |  |  |  | 8,971 |
Treasury stock — 2,081,597 shares at September 30, 2021 and 2,151,437 shares at December 31, 2020, at cost |  | (66,315) |  |  |  | (68,612) |
Total Shareholders’ Equity |  | 1,201,681 |  |  |  | 1,154,711 |
Total Liabilities and Shareholders’ Equity |  | $ | 9,436,054 |  |  |  | $ | 8,967,897 |

See Notes to Consolidated Financial Statements
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S&T BANCORP, INC. AND SUBSIDIARIES
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS)
(Unaudited)

| Three Months Ended September 30, |  | Nine Months Ended September 30,
(dollars in thousands, except per share data) | 2021 |  | 2020 |  | 2021 |  | 2020
INTEREST AND DIVIDEND INCOME |  |  |  |  |  |  |  |  |  |  |
Loans, including fees |  | $ | 66,914 |  |  |  | $ | 72,263 |  |  |  | $ | 204,088 |  |  |  | $ | 229,812 |
Investment Securities: |  |  |  |  |  |  |  |  |  |  |
Taxable |  | 4,176 |  |  |  | 3,473 |  |  |  | 11,532 |  |  |  | 11,547 |
Tax-exempt |  | 595 |  |  |  | 885 |  |  |  | 2,098 |  |  |  | 2,646 |
Dividends |  | 84 |  |  |  | 227 |  |  |  | 409 |  |  |  | 911 |
Total Interest and Dividend Income |  | 71,769 |  |  |  | 76,848 |  |  |  | 218,127 |  |  |  | 244,916 |
INTEREST EXPENSE |  |  |  |  |  |  |  |  |  |  |
Deposits |  | 2,439 |  |  |  | 6,626 |  |  |  | 8,572 |  |  |  | 31,191 |
Borrowings and junior subordinated debt securities |  | 619 |  |  |  | 946 |  |  |  | 1,881 |  |  |  | 4,265 |
Total Interest Expense |  | 3,058 |  |  |  | 7,572 |  |  |  | 10,453 |  |  |  | 35,456 |
NET INTEREST INCOME |  | 68,711 |  |  |  | 69,276 |  |  |  | 207,674 |  |  |  | 209,460 |
Provision for credit losses |  | (3,388) |  |  |  | (17,485) |  |  |  | (9,087) |  |  |  | (124,294) |
Net Interest Income After Provision for Credit Losses |  | 65,323 |  |  |  | 51,791 |  |  |  | 198,587 |  |  |  | 85,166 |
NONINTEREST INCOME |  |  |  |  |  |  |  |  |  |  |
Net gain on sale of securities |  | — |  |  |  | — |  |  |  | 29 |  |  |  | 142 |
Debit and credit card |  | 4,579 |  |  |  | 4,171 |  |  |  | 13,486 |  |  |  | 11,264 |
Service charges on deposit accounts |  | 3,923 |  |  |  | 3,303 |  |  |  | 11,039 |  |  |  | 10,124 |
Wealth management |  | 3,464 |  |  |  | 2,522 |  |  |  | 9,576 |  |  |  | 7,471 |
Mortgage banking |  | 2,162 |  |  |  | 3,964 |  |  |  | 8,206 |  |  |  | 7,823 |
Commercial loan swap income |  | 184 |  |  |  | 499 |  |  |  | 577 |  |  |  | 3,928 |
Other |  | 1,534 |  |  |  | 2,024 |  |  |  | 5,595 |  |  |  | 3,358 |
Total Noninterest Income |  | 15,846 |  |  |  | 16,483 |  |  |  | 48,507 |  |  |  | 44,110 |
NONINTEREST EXPENSE |  |  |  |  |  |  |  |  |  |  |
Salaries and employee benefits |  | 25,228 |  |  |  | 24,571 |  |  |  | 73,070 |  |  |  | 67,326 |
Data processing and information technology |  | 4,001 |  |  |  | 4,218 |  |  |  | 12,012 |  |  |  | 11,671 |
Occupancy |  | 3,660 |  |  |  | 3,441 |  |  |  | 10,921 |  |  |  | 10,643 |
Furniture, equipment and software |  | 2,745 |  |  |  | 2,440 |  |  |  | 7,787 |  |  |  | 7,965 |
Other taxes |  | 1,830 |  |  |  | 1,612 |  |  |  | 5,098 |  |  |  | 4,816 |
Professional services and legal |  | 1,550 |  |  |  | 1,911 |  |  |  | 4,718 |  |  |  | 4,890 |
Marketing |  | 890 |  |  |  | 1,793 |  |  |  | 3,208 |  |  |  | 3,883 |
FDIC insurance |  | 1,210 |  |  |  | 1,900 |  |  |  | 3,180 |  |  |  | 3,718 |
Merger related expenses |  | — |  |  |  | — |  |  |  | — |  |  |  | 2,342 |
Other |  | 6,127 |  |  |  | 6,360 |  |  |  | 18,656 |  |  |  | 20,861 |
Total Noninterest Expense |  | 47,241 |  |  |  | 48,246 |  |  |  | 138,650 |  |  |  | 138,115 |
Income (Loss) Before Taxes |  | 33,928 |  |  |  | 20,028 |  |  |  | 108,444 |  |  |  | (8,839) |
Income tax expense (benefit) |  | 6,330 |  |  |  | 3,323 |  |  |  | 20,578 |  |  |  | (5,703) |
Net Income (Loss) |  | $ | 27,598 |  |  |  | $ | 16,705 |  |  |  | $ | 87,866 |  |  |  | $ | (3,136) |
Earnings per share—basic |  | $ | 0.71 |  |  |  | $ | 0.43 |  |  |  | $ | 2.25 |  |  |  | $ | (0.08) |
Earnings per share—diluted |  | $ | 0.70 |  |  |  | $ | 0.43 |  |  |  | $ | 2.24 |  |  |  | $ | (0.08) |
Dividends declared per share |  | $ | 0.28 |  |  |  | $ | 0.28 |  |  |  | $ | 0.84 |  |  |  | $ | 0.84 |
Comprehensive Income |  | $ | 22,964 |  |  |  | $ | 16,926 |  |  |  | $ | 77,866 |  |  |  | $ | 17,967 |

See Notes to Consolidated Financial Statements
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S&T BANCORP, INC. AND SUBSIDIARIES
CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY
(Unaudited)

| For the three months ended September 30, 2020
(dollars in thousands, except share and per share data) | Common Stock |  | Additional Paid-in Capital |  | Retained Earnings |  | Accumulated Other Comprehensive Income |  | Treasury Stock |  | Total
Balance at June 30, 2020 |  | $ | 103,623 |  |  |  | $ | 400,417 |  |  |  | $ | 692,240 |  |  |  | $ | 9,232 |  |  |  | $ | (69,735) |  |  |  | $ | 1,135,777 |
Net income for the three months ended September 30, 2020 |  | — |  |  |  | — |  |  |  | 16,705 |  |  |  | — |  |  |  | — |  |  |  | 16,705 |
Other comprehensive income, net of tax |  | — |  |  |  | — |  |  |  | — |  |  |  | 221 |  |  |  | — |  |  |  | 221 |
Cash dividends declared ($0.28 per share) |  | — |  |  |  | — |  |  |  | (10,960) |  |  |  | — |  |  |  | — |  |  |  | (10,960) |
Forfeitures of restricted stock awards 11,822 shares |  | — |  |  |  | — |  |  |  | 366 |  |  |  | — |  |  |  | (366) |  |  |  | — |
Recognition of restricted stock compensation expense |  | — |  |  |  | 372 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 372 |
Balance at September 30, 2020 |  | $ | 103,623 |  |  |  | $ | 400,789 |  |  |  | $ | 698,351 |  |  |  | $ | 9,453 |  |  |  | $ | (70,101) |  |  |  | $ | 1,142,115 |
See Notes to Consolidated Financial Statements |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
| For the three months ended September 30, 2021
(dollars in thousands, except share and per share data) | Common Stock |  | Additional Paid-in Capital |  | Retained Earnings |  | Accumulated Other Comprehensive Income (Loss) |  | Treasury Stock |  | Total
Balance at June 30, 2021 |  | $ | 103,623 |  |  |  | $ | 402,053 |  |  |  | $ | 746,472 |  |  |  | $ | 3,605 |  |  |  | $ | (67,020) |  |  |  | $ | 1,188,733 |
Net income for the three months ended September 30, 2021 |  | — |  |  |  | — |  |  |  | 27,598 |  |  |  | — |  |  |  | — |  |  |  | 27,598 |
Other comprehensive loss, net of tax |  | — |  |  |  | — |  |  |  | — |  |  |  | (4,634) |  |  |  | — |  |  |  | (4,634) |
Cash dividends declared ($0.28 per share) |  | — |  |  |  | — |  |  |  | (10,991) |  |  |  | — |  |  |  | — |  |  |  | (10,991) |
Treasury stock issued for restricted stock awards of 25,459 shares, net of forfeitures of 3,331 |  | — |  |  |  | — |  |  |  | (705) |  |  |  | — |  |  |  | 705 |  |  |  | — |
Recognition of restricted stock compensation expense |  | — |  |  |  | 975 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 975 |
Balance at September 30, 2021 |  | $ | 103,623 |  |  |  | $ | 403,028 |  |  |  | $ | 762,374 |  |  |  | $ | (1,029) |  |  |  | $ | (66,315) |  |  |  | $ | 1,201,681 |
See Notes to Consolidated Financial Statements |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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S&T BANCORP, INC. AND SUBSIDIARIES
CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY
(Unaudited)

| Nine months ended September 30, 2020
(dollars in thousands, except share and per share data) | Common Stock |  | Additional Paid-in Capital |  | Retained Earnings |  | Accumulated Other Comprehensive (Loss) Income |  | Treasury Stock |  | Total
Balance at January 1, 2020 |  | $ | 103,623 |  |  |  | $ | 399,944 |  |  |  | $ | 761,083 |  |  |  | $ | (11,670) |  |  |  | $ | (60,982) |  |  |  | $ | 1,191,998 |
Net loss for the nine months ended September 30, 2020 |  | — |  |  |  | — |  |  |  | (3,136) |  |  |  | — |  |  |  | — |  |  |  | (3,136) |
Other comprehensive income, net of tax |  | — |  |  |  | — |  |  |  | — |  |  |  | 21,123 |  |  |  | — |  |  |  | 21,123 |
Adoption of accounting standard - credit losses |  | — |  |  |  | — |  |  |  | (22,590) |  |  |  | — |  |  |  | — |  |  |  | (22,590) |
Cash dividends declared ($0.84 per share) |  | — |  |  |  | — |  |  |  | (32,972) |  |  |  | — |  |  |  | — |  |  |  | (32,972) |
Treasury stock issued for restricted stock awards (147,034 shares, net of forfeitures of 44,270 shares) |  | — |  |  |  | — |  |  |  | (4,034) |  |  |  | — |  |  |  | 3,440 |  |  |  | (594) |
Repurchase of common stock (411,430 shares) |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | (12,559) |  |  |  | (12,559) |
Recognition of restricted stock compensation expense |  | — |  |  |  | 845 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 845 |
Balance at September 30, 2020 |  | $ | 103,623 |  |  |  | $ | 400,789 |  |  |  | $ | 698,351 |  |  |  | $ | 9,453 |  |  |  | $ | (70,101) |  |  |  | $ | 1,142,115 |
| Nine months ended September 30, 2021
(dollars in thousands, except share and per share data) | Common Stock |  | Additional Paid-in Capital |  | Retained Earnings |  | Accumulated Other Comprehensive Income (Loss) |  | Treasury Stock |  | Total
Balance at January 1, 2021 |  | $ | 103,623 |  |  |  | $ | 400,668 |  |  |  | $ | 710,061 |  |  |  | $ | 8,971 |  |  |  | $ | (68,612) |  |  |  | $ | 1,154,711 |
Net income for the nine months ended September 30, 2021 |  | — |  |  |  | — |  |  |  | 87,866 |  |  |  | — |  |  |  | — |  |  |  | 87,866 |
Other comprehensive loss, net of tax |  | — |  |  |  | — |  |  |  | — |  |  |  | (10,000) |  |  |  | — |  |  |  | (10,000) |
Cash dividends declared ($0.84 per share) |  | — |  |  |  | — |  |  |  | (32,954) |  |  |  | — |  |  |  | — |  |  |  | (32,954) |
Treasury stock issued for restricted stock awards (125,170 shares, net of forfeitures of 55,330 shares) |  | — |  |  |  | — |  |  |  | (2,599) |  |  |  | — |  |  |  | 2,297 |  |  |  | (302) |
Recognition of restricted stock compensation expense |  | — |  |  |  | 2,360 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 2,360 |
Balance at September 30, 2021 |  | $ | 103,623 |  |  |  | $ | 403,028 |  |  |  | $ | 762,374 |  |  |  | $ | (1,029) |  |  |  | $ | (66,315) |  |  |  | $ | 1,201,681 |

See Notes to Consolidated Financial Statements
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S&T BANCORP, INC. AND SUBSIDIARIES
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS
(Unaudited)

| Nine Months Ended September 30, |
(dollars in thousands) |  | 2021 |  |  | 2020 |
Net Cash Provided by (Used in) Operating Activities |  | $ | 171,740 |  |  |  | $ | (3,002) |  |
INVESTING ACTIVITIES |  |  |  |  |  |
Purchases of securities |  | (226,971) |  |  |  | (90,348) |  |
Proceeds from maturities, prepayments and calls of securities |  | 109,499 |  |  |  | 176,103 |  |
Proceeds from sales of securities |  | 1,917 |  |  |  | 1,349 |  |
Net proceeds from sales of Federal Home Loan Bank stock |  | 3,137 |  |  |  | 7,200 |  |
Net decrease (increase) in loans |  | 220,854 |  |  |  | (350,884) |  |
Proceeds from sale of portfolio loans |  | 3,438 |  |  |  | — |  |
Purchases of premises and equipment |  | (2,110) |  |  |  | (4,356) |  |
Proceeds from the sale of premises and equipment |  | 14 |  |  |  | 15 |  |
Proceeds from life insurance settlement |  | 353 |  |  |  | — |  |
Net Cash Provided by (Used in) Investing Activities |  | 110,131 |  |  |  | (260,921) |  |
FINANCING ACTIVITIES |  |  |  |  |  |
Net increase in core deposits |  | 710,776 |  |  |  | 746,580 |  |
Net decrease in certificates of deposit |  | (186,115) |  |  |  | (148,573) |  |
Net increase in securities sold under repurchase agreements |  | 7,423 |  |  |  | 22,818 |  |
Net decrease in short-term borrowings |  | (75,000) |  |  |  | (198,319) |  |
Repayments on long-term borrowings |  | (988) |  |  |  | (1,792) |  |
Treasury shares issued-net |  | (302) |  |  |  | (594) |  |
Cash dividends paid to common shareholders |  | (32,954) |  |  |  | (32,972) |  |
Repurchase of common stock |  | — |  |  |  | (12,559) |  |
Net Cash Provided by Financing Activities |  | 422,840 |  |  |  | 374,589 |  |
Net increase in cash and cash equivalents |  | 704,711 |  |  |  | 110,666 |  |
Cash and cash equivalents at beginning of period |  | 229,666 |  |  |  | 197,823 |  |
Cash and Cash Equivalents at End of Period |  | $ | 934,377 |  |  |  | $ | 308,489 |  |
Supplemental Disclosures |  |  |  |  |  |
Loans transferred to held for sale |  | $ | 4,467 |  |  |  | $ | — |  |
Interest paid |  | $ | 12,200 |  |  |  | $ | 37,437 |  |
Income taxes paid, net of refunds |  | $ | 19,183 |  |  |  | $ | 6,210 |  |
Transfers of loans to other real estate owned |  | $ | 12,392 |  |  |  | $ | 631 |  |

See Notes to Consolidated Financial Statements
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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
NOTE 1. BASIS OF PRESENTATION
Principles of Consolidation
The interim Consolidated Financial Statements include the accounts of S&T Bancorp, Inc., or S&T, and its wholly owned subsidiaries. All significant intercompany transactions have been eliminated in consolidation. Investments of 20 percent to 50 percent of the outstanding common stock of investees are accounted for using the equity method of accounting.
Basis of Presentation
The accompanying unaudited interim Consolidated Financial Statements of S&T have been prepared in accordance with generally accepted accounting principles, or GAAP, in the United States for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements and should be read in conjunction with the audited Consolidated Financial Statements included in our Annual Report on Form 10-K for the year ended December 31, 2020, filed with the Securities and Exchange Commission, or SEC, on March 1, 2021. In the opinion of management, the accompanying interim financial information reflects all adjustments, consisting of normal recurring adjustments, necessary to present fairly our financial position and the results of operations for each of the interim periods presented. Results of operations for interim periods are not necessarily indicative of the results of operations that may be expected for a full year or any future period.
On June 5, 2019 we entered into an agreement to acquire DNB Financial Corporation, or DNB, and the transaction was completed on November 30, 2019. Refer to Note 2, Business Combinations in our Annual Report on Form 10-K for the year ended December 31, 2020 for further details on the merger.
Reclassification
A mounts in prior period financial statements and footnotes are reclassified whenever necessary to conform to the current period presentation. Reclassifications had no effect on our results of operations or financial condition.
Use of Estimates
The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements. Actual results could differ from those estimates.
Recently Adopted Accounting Standards Updates, or ASU or Update
Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes
In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes. The amendments in this ASU simplify the accounting for income taxes by removing certain exceptions and improve the consistent application of GAAP by clarifying and amending other existing guidance. We adopted this ASU on January 1, 2021. The amendments in this ASU did not impact our consolidated financial statements.
Amendments to certain SEC paragraphs from the Codification in response to issuance of SEC Final Rules (Topics 205 and 946)
In August 2021, the FASB issued ASU No. 2021-06, which amends certain SEC paragraphs from the Codification in response to the issuance of SEC Final Rule Nos. 33-10786, Amendments to Financial Disclosures About Acquired and Disposed Businesses, and 33-10835, Update of Statistical Disclosures for Bank and Savings and Loan Registrants. We adopted this ASU in August 2021. The amendments in this ASU did not impact our consolidated financial statements.
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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 1. BASIS OF PRESENTATION - continued
Accounting Standards Issued Not Yet Adopted
Reference Rate Reform (Topic 848) Facilitation of the Effects of Reference Rate Reform on Financial Reporting
In March 2020, the FASB issued ASU No. 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting. The amendments in this ASU provide optional guidance for a limited period of time to ease the potential burden in accounting for or recognizing the effects of reference rate reform on financial reporting. The amendments provide optional expedients and exceptions for applying GAAP to loan and lease agreements, derivative contracts, and other transactions affected by the anticipated transition away from LIBOR toward new interest rate benchmarks. Modified contracts that meet certain scope guidance are eligible for relief from the modification accounting requirements in GAAP. The optional guidance generally allows for the modified contract to be accounted for as a continuation of the existing contract and does not require contract remeasurement at the modification date or reassessment of a previous accounting determination. The amendments in this ASU are effective as of March 12, 2020 through December 31, 2022. We have established a committee to guide our transition from LIBOR and have begun efforts to transition to alternative rates consistent with industry timelines. We have identified products that utilize LIBOR and are revising fallback language to facilitate the transition to alternative reference rates. ASU 2020-04 is not expected to have a material impact on our consolidated financial statements.
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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 2. EARNINGS PER SHARE
Diluted earnings per share is calculated using both the two-class and the treasury stock methods with the more dilutive method used to determine diluted earnings per share. For the three and nine months ended September 30, 2021 and 2020, diluted EPS was reported using the two-class method. The following table reconciles the numerators and denominators of basic and diluted earnings per share calculations for the periods presented.

| Three Months Ended September 30, |  | Nine months ended September 30,
(in thousands, except share and per share data) | 2021 |  | 2020 |  | 2021 |  | 2020
Numerator for Earnings per Share—Basic: |  |  |  |  |  |  |  |  |  |  |
Net income (loss) |  | $ | 27,598 |  |  |  | $ | 16,705 |  |  |  | $ | 87,866 |  |  |  | $ | (3,136) |
Less: Income allocated to participating shares |  | 125 |  |  |  | 52 |  |  |  | 408 |  |  |  | — |
Net Income Allocated to Shareholders |  | $ | 27,473 |  |  |  | $ | 16,653 |  |  |  | $ | 87,458 |  |  |  | $ | (3,136) |
Numerator for Earnings per Share—Diluted: |  |  |  |  |  |  |  |  |  |  |
Net income (loss) |  | $ | 27,598 |  |  |  | $ | 16,705 |  |  |  | $ | 87,866 |  |  |  | $ | (3,136) |
Net Income Available to Shareholders |  | $ | 27,598 |  |  |  | $ | 16,705 |  |  |  | $ | 87,866 |  |  |  | $ | (3,136) |
Denominators for Earnings per Share: |  |  |  |  |  |  |  |  |  |  |
Weighted Average Shares Outstanding—Basic |  | 39,060,616 |  |  |  | 39,020,811 |  |  |  | 39,044,412 |  |  |  | 39,101,309 |
Add: Potentially dilutive shares |  | 86,157 |  |  |  | 20,656 |  |  |  | 89,194 |  |  |  | — |
Denominator for Treasury Stock Method—Diluted |  | 39,146,773 |  |  |  | 39,041,467 |  |  |  | 39,133,606 |  |  |  | 39,101,309 |
Weighted Average Shares Outstanding—Basic |  | 39,060,616 |  |  |  | 39,020,811 |  |  |  | 39,044,412 |  |  |  | 39,101,309 |
Add: Average participating shares outstanding |  | 1,464 |  |  |  | — |  |  |  | 458 |  |  |  | — |
Denominator for Two-Class Method—Diluted |  | 39,062,080 |  |  |  | 39,020,811 |  |  |  | 39,044,870 |  |  |  | 39,101,309 |
Earnings (loss) per share—basic |  | $ | 0.71 |  |  |  | $ | 0.43 |  |  |  | $ | 2.25 |  |  |  | $ | (0.08) |
Earnings (loss) per share—diluted |  | $ | 0.70 |  |  |  | $ | 0.43 |  |  |  | $ | 2.24 |  |  |  | $ | (0.08) |
Restricted stock considered anti-dilutive excluded from potentially dilutive shares |  | 163 |  |  |  | 19,449 |  |  |  | 615 |  |  |  | 1,137 |

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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 3. FAIR VALUE MEASUREMENTS
We use fair value measurements when recording and disclosing certain financial assets and liabilities. Debt securities, equity securities and derivative financial instruments are recorded at fair value on a recurring basis. Additionally, from time to time, we may be required to record other assets at fair value on a nonrecurring basis, such as loans held for sale, individually assessed loans, other real estate owned, or OREO, and other repossessed assets, mortgage servicing rights, or MSRs, and certain other assets.
Fair value is the price that would be received to sell an asset or paid to transfer a liability in the principal or most advantageous market in an orderly transaction between market participants at the measurement date. An orderly transaction is a transaction that assumes exposure to the market for a period prior to the measurement date to allow for marketing activities that are usual and customary for transactions involving such assets or liabilities; it is not a forced transaction. In determining fair value, we use various valuation approaches, including market, income and cost approaches. The fair value standard establishes a hierarchy for inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that observable inputs be used when available. Observable inputs are inputs that market participants would use in pricing an asset or liability, which are developed based on market data that we have obtained from independent sources. Unobservable inputs reflect our estimates of assumptions that market participants would use in pricing an asset or liability, which are developed based on the best information available in the circumstances.
The fair value hierarchy gives the highest priority to unadjusted quoted market prices in active markets for identical assets or liabilities (Level 1 measurement) and the lowest priority to unobservable inputs (Level 3 measurement). The fair value hierarchy is broken down into three levels based on the reliability of inputs as follows:
Level 1: valuation is based upon unadjusted quoted market prices for identical instruments traded in active markets.
Level 2: valuation is based upon quoted market prices for similar instruments traded in active markets, quoted market prices for identical or similar instruments traded in markets that are not active and model-based valuation techniques for which all significant assumptions are observable in the market or can be corroborated by market data.
Level 3: valuation is derived from other valuation methodologies, including discounted cash flow models and similar techniques that use significant assumptions not observable in the market. These unobservable assumptions reflect estimates of assumptions that market participants would use in determining fair value.
A financial instrument’s level within the fair value hierarchy is based on the lowest level of input that is significant to the fair value measurement. Our policy is to recognize transfers between any of the fair value hierarchy levels at the end of the reporting period in which the transfer occurred.
The following are descriptions of the valuation methodologies that we use for financial instruments recorded at fair value on either a recurring or nonrecurring basis.
Recurring Basis
Available-for-Sale Debt Securities
We obtain fair values for debt securities from a third-party pricing service which utilizes several sources for valuing fixed-income securities. We validate prices received from our pricing service through comparison to a secondary pricing service and broker quotes. We review the methodologies of the pricing services which provide us with a sufficient understanding of the valuation models, assumptions, inputs and pricing to reasonably measure the fair value of our debt securities. The fair value of U.S. treasury securities are based on quoted market prices in active markets and are classified as Level 1. The market valuation sources for other debt securities include observable inputs rather than significant unobservable inputs and are classified as Level 2. The service provider utilizes pricing models that vary by asset class and include available trade, bid and other market information. Generally, the methodologies include broker quotes, proprietary models and extensive quality control programs.
Equity Securities
Marketable equity securities that have an active, quotable market are classified as Level 1. Marketable equity securities that are quotable, but are thinly traded or inactive, are classified as Level 2. Marketable equity securities that are not readily traded and do not have a quotable market are classified as Level 3.
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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 3. FAIR VALUE MEASUREMENTS - continued
Securities Held in a Deferred Compensation Plan
We use quoted market prices to determine the fair value of our equity security assets. These securities are reported at fair value with the gains and losses included in noninterest income in our Condensed Consolidated Statements of Comprehensive Income (Loss). These assets are held in a deferred compensation plan and are invested in readily quoted mutual funds. Accordingly, these assets are classified as Level 1. Deferred compensation plan assets are reported in other assets in the Consolidated Balance Sheets.
Derivative Financial Instruments
We use derivative instruments, including interest rate swaps for commercial loans with our customers, interest rate lock commitments and forward commitments related to the sale of mortgage loans in the secondary market. We calculate the fair value for derivatives using accepted valuation techniques, including discounted cash flow analysis on the expected cash flows of each derivative. Each valuation considers the contractual terms of the derivative, including the period to maturity, and uses observable market-based inputs, such as interest rate curves and implied volatilities. Accordingly, interest rate swaps for commercial loans are classified as Level 2. Interest rate lock commitments and forward commitments related to mortgage loans are classified as Level 3 due to significant unobservable inputs. We incorporate credit valuation adjustments into the valuation models to appropriately reflect both our own nonperformance risk and the respective counterparties’ nonperformance risk in calculating fair value measurements. In adjusting the fair value of our derivative contracts for the effect of nonperformance risk, we have considered the impact of netting and any applicable credit enhancements and collateral postings.
Nonrecurring Basis
Loans Held for Sale
Loans held for sale are carried at the lower of cost or market and consist of 1-4 family residential loans originated for sale in the secondary market and, from time to time, certain loans are transferred from the loan portfolio to loans held for sale, all of which are carried at the lower of cost or fair value. The fair value of 1-4 family residential loans is based on the principal or most advantageous market currently offered for similar loans using observable market data. The fair value of the loans transferred from the loan portfolio is based on the amounts offered for these loans in currently pending sales transactions. Loans held for sale marked to fair value are classified as Level 2.
Loans Individually Evaluated
Loans that are individually evaluated to determine whether a specific allocation of ACL is needed are reported at the lower of amortized cost or fair value. Fair value is determined using the following methods: 1) the present value of expected future cash flows discounted at the loan’s original effective interest rate; 2) the loan’s observable market price; or 3) the fair value of the collateral less estimated selling costs when the loan is collateral dependent and we expect to liquidate the collateral. However, if repayment is expected to come from the operation of the collateral, rather than liquidation, then we do not consider estimated selling costs in determining the fair value of the collateral. Collateral values are generally based upon appraisals by approved, independent state certified appraisers. Appraisals may be discounted based on our historical knowledge, changes in market conditions from the time of appraisal or our knowledge of the borrower and the borrower’s business. Loans individually evaluated that are marked to fair value are classified as Level 3.
OREO and Other Repossessed Assets
OREO and other repossessed assets obtained in partial or total satisfaction of a loan are recorded at the lower of recorded investment in the loan or fair value less cost to sell. Subsequent to foreclosure, these assets are carried at the lower of the amount recorded at acquisition date or fair value less cost to sell. Accordingly, it may be necessary to record nonrecurring fair value adjustments. Fair value, when recorded, is generally based upon appraisals by approved, independent state certified appraisers. Appraisals on OREO may be discounted based on our historical knowledge, changes in market conditions from the time of appraisal or other information available to us. OREO and other repossessed assets marked to fair value are classified as Level 3. OREO and other repossessed assets are reported in other assets in the Consolidated Balance Sheets.
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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 3. FAIR VALUE MEASUREMENTS - continued
Mortgage Servicing Rights
MSRs are reported pursuant to the amortization method and evaluated for impairment quarterly by comparing the carrying to the fair value of the MSRs. Fair value of MSRs is determined by calculating the present value of estimated future net servicing cash flows, considering expected mortgage loan prepayment rates, discount rates, servicing costs and other economic factors, which are determined based on current market conditions. The expected rate of mortgage loan prepayments is the most significant factor driving the value of MSRs. MSRs are considered impaired if the carrying value exceeds fair value. Since the valuation model includes significant unobservable inputs as listed above, MSRs are classified as Level 3. MSRs are reported in other assets in the Consolidated Balance Sheets and are amortized into mortgage banking income in the Condensed Consolidated Statements of Comprehensive Income (Loss).
Financial Instruments
In addition to financial instruments recorded at fair value in our financial statements, fair value accounting guidance requires disclosure of the fair value of all of an entity’s assets and liabilities that are considered financial instruments. The majority of our assets and liabilities are considered financial instruments. Many of these instruments lack an available trading market as characterized by a willing buyer and a willing seller engaged in an exchange transaction. Also, it is our general practice and intent to hold our financial instruments to maturity and to not engage in trading or sales activities with respect to such financial instruments. For fair value disclosure purposes, we substantially utilize the fair value measurement criteria as required and explained above. In cases where quoted fair values are not available, we use present value methods to determine the fair value of our financial instruments.
Cash and Cash Equivalents
The carrying amounts reported in the Consolidated Balance Sheets for cash and due from banks, including interest-bearing deposits, approximate fair value.
Loans
Our methodology to fair value loans includes an exit price notion. The fair value of variable rate loans that may reprice frequently at short-term market rates is based on carrying values adjusted for liquidity and credit risk. The fair value of variable rate loans that reprice at intervals of one year or longer, such as adjustable-rate mortgage products, is estimated using discounted cash flow analyses that utilize interest rates currently being offered for similar loans and adjusted for liquidity and credit risk. The fair value of fixed rate loans is estimated using a discounted cash flow analysis that utilizes interest rates currently being offered for similar loans adjusted for liquidity and credit risk.
Federal Home Loan Bank, or FHLB, and Other Restricted Stock
It is not practical to determine the fair value of our FHLB and other restricted stock due to the restrictions placed on the transferability of these stocks; it is presented at carrying value.
Collateral Receivable
Collateral receivable is cash that is made available to counterparties as collateral for our interest rate swaps. The carrying amount included in other assets on our Consolidated Balance Sheets approximates fair value.
Deposits
The fair values disclosed for deposits without defined maturities (e.g., noninterest and interest-bearing demand, money market and savings accounts) are by definition equal to the amounts payable on demand. The carrying amounts for variable rate, fixed-term time deposits approximate their fair values. Estimated fair values for fixed rate and other time deposits are based on discounted cash flow analysis using interest rates currently offered for time deposits with similar terms.
Short-Term Borrowings
The carrying amounts of securities sold under repurchase agreements, or REPOs, and other short-term borrowings approximate their fair values.
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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 3. FAIR VALUE MEASUREMENTS - continued
Long-Term Borrowings
The fair values disclosed for fixed-rate long-term borrowings are determined by discounting their contractual cash flows using current interest rates for long-term borrowings of similar remaining maturities. The carrying amounts of variable rate long-term borrowings approximate their fair values.
Junior Subordinated Debt Securities
The interest rate on the variable-rate junior subordinated debt securities is reset quarterly; therefore, the carrying values approximate their fair values.
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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 3. FAIR VALUE MEASUREMENTS - continued
Assets and Liabilities Recorded at Fair Value on a Recurring Basis
The following tables present our assets and liabilities that are measured at fair value on a recurring basis by fair value hierarchy level at September 30, 2021 and December 31, 2020.

| September 30, 2021
(dollars in thousands) | Level 1 |  | Level 2 |  | Level 3 |  | Total
ASSETS |  |  |  |  |  |  |
Available-for-sale debt securities: |  |  |  |  |  |  |
U.S. Treasury securities | $ | 85,300 |  |  | $ | — |  |  | $ | — |  |  | $ | 85,300 |
Obligations of U.S. government corporations and agencies | — |  |  | 71,205 |  |  | — |  |  | 71,205 |
Collateralized mortgage obligations of U.S. government corporations and agencies | — |  |  | 208,985 |  |  | — |  |  | 208,985 |
Residential mortgage-backed securities of U.S. government corporations and agencies | — |  |  | 60,442 |  |  | — |  |  | 60,442 |
Commercial mortgage-backed securities of U.S. government corporations and agencies | — |  |  | 356,506 |  |  | — |  |  | 356,506 |
Corporate obligations | — |  |  | 500 |  |  | — |  |  | 500 |
Obligations of states and political subdivisions | — |  |  | 86,056 |  |  | — |  |  | 86,056 |
Total Available-for-sale Debt Securities | 85,300 |  |  | 783,694 |  |  | — |  |  | 868,994 |
Marketable equity securities | 1,051 |  |  | 76 |  |  | — |  |  | 1,127 |
Total Securities | 86,351 |  |  | 783,770 |  |  | — |  |  | 870,121 |
Securities held in a deferred compensation plan | 9,320 |  |  | — |  |  | — |  |  | 9,320 |
Derivative financial assets: |  |  |  |  |  |  |
Interest rate swaps | — |  |  | 42,177 |  |  | — |  |  | 42,177 |
Interest rate lock commitments | — |  |  | — |  |  | 812 |  |  | 812 |
Forward sale contracts | — |  |  | — |  |  | 101 |  |  | 101 |
Total Assets | $ | 95,671 |  |  | $ | 825,947 |  |  | $ | 913 |  |  | $ | 922,531 |
LIABILITIES |  |  |  |  |  |  |
Derivative financial liabilities: |  |  |  |  |  |  |
Interest rate swaps | $ | — |  |  | $ | 42,554 |  |  | $ | — |  |  | $ | 42,554 |
Total Liabilities | $ | — |  |  | $ | 42,554 |  |  | $ | — |  |  | $ | 42,554 |

| December 31, 2020
(dollars in thousands) | Level 1 |  | Level 2 |  | Level 3 |  | Total
ASSETS |  |  |  |  |  |  |
Available-for-sale debt securities: |  |  |  |  |  |  |
U.S. Treasury securities | $ | 10,282 |  |  | $ | — |  |  | $ | — |  |  | $ | 10,282 |
Obligations of U.S. government corporations and agencies | — |  |  | 82,904 |  |  | — |  |  | 82,904 |
Collateralized mortgage obligations of U.S. government corporations and agencies | — |  |  | 209,296 |  |  | — |  |  | 209,296 |
Residential mortgage-backed securities of U.S. government corporations and agencies | — |  |  | 67,778 |  |  | — |  |  | 67,778 |
Commercial mortgage-backed securities of U.S. government corporations and agencies | — |  |  | 273,681 |  |  | — |  |  | 273,681 |
Corporate obligations | — |  |  | 2,025 |  |  | — |  |  | 2,025 |
Obligations of states and political subdivisions | — |  |  | 124,427 |  |  | — |  |  | 124,427 |
Total Available-for-sale Debt Securities | 10,282 |  |  | 760,111 |  |  | — |  |  | 770,393 |
Marketable equity securities | 3,228 |  |  | 72 |  |  | — |  |  | 3,300 |
Total Securities | 13,510 |  |  | 760,183 |  |  | — |  |  | 773,693 |
Securities held in a deferred compensation plan | 6,794 |  |  | — |  |  | — |  |  | 6,794 |
Derivative financial assets: |  |  |  |  |  |  |
Interest rate swaps | — |  |  | 78,319 |  |  | — |  |  | 78,319 |
Interest rate lock commitments | — |  |  | — |  |  | 2,900 |  |  | 2,900 |
Total Assets | $ | 20,304 |  |  | $ | 838,502 |  |  | $ | 2,900 |  |  | $ | 861,706 |
LIABILITIES |  |  |  |  |  |  |
Derivative financial liabilities: |  |  |  |  |  |  |
Interest rate swaps | $ | — |  |  | $ | 79,033 |  |  | $ | — |  |  | $ | 79,033 |
Forward sale contracts | — |  |  | 385 |  |  | — |  |  | 385 |
Total Liabilities | $ | — |  |  | $ | 79,418 |  |  | $ | — |  |  | $ | 79,418 |

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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 3. FAIR VALUE MEASUREMENTS - continued
Loans held for sale were transferred to Level 2 from Level 3 during the nine months ended September 30, 2021. Interest rate lock commitments to borrowers were transferred from Level 2 to Level 3 during the year ended December 31, 2020 due to pull-through factors being a significant unobservable input.
Assets Recorded at Fair Value on a Nonrecurring Basis
We may be required to measure certain assets and liabilities at fair value on a nonrecurring basis. Nonrecurring assets are recorded at the lower of cost or fair value in our financial statements. There were no liabilities measured at fair value on a nonrecurring basis at either September 30, 2021 or December 31, 2020.
For Level 3 assets measured at fair value on a nonrecurring basis as of September 30, 2021 and December 31, 2020, the significant unobservable inputs used in the fair value measurements were as follows:

| September 30, 2021 |  | Valuation Technique |  |  | Significant Unobservable Inputs |  | Range | Weighted Average (1) (2) (3)
(dollars in thousands) |  |  |  |
Loans individually evaluated | $ | 41,135 |  |  | Collateral method |  |  | Appraisal adjustment |  | —% | - | 17.00% | 13.68%
Other real estate owned | 13,313 |  |  | Collateral method |  |  | Costs to sell |  | 4.00% | - | 7.00% | 6.77%
Mortgage servicing rights | 7,015 |  |  | Discounted cash flow method |  |  | Discount rate |  | 9.21% | - | 12.54% | 9.38%
|  |  | Constant prepayment rates |  | 7.93% | - | 14.96% | 10.69%
Loans held for sale | 1,669 |  |  | Contractual agreement |  |  | None |  | NA | NA
Total Assets | $ | 63,132 |  |  |  |  |  |  |  |  |  |  |  |

| December 31, 2020 |  | Valuation Technique |  |  | Significant Unobservable Inputs |  | Range | Weighted Average (1) (2) (3)
(dollars in thousands) |  |  |  |
Loans individually evaluated | $ | 67,402 |  |  | Collateral method |  |  | Appraisal adjustment |  | —% | - | 47.00% | 16.90%
Other real estate owned | 1,953 |  |  | Collateral method |  |  | Costs to sell |  | 4.00% | - | 7.00% | 4.92%
Mortgage servicing rights | 4,976 |  |  | Discounted cash flow method |  |  | Discount rate |  | 9.24% | - | 12.55% | 9.42%
|  |  | Constant prepayment rates |  | 8.82% | - | 14.58% | 13.37%
Loans held for sale | 586 |  |  | Contractual agreement |  |  | None |  | NA | NA
Total Assets | $ | 74,917 |  |  |  |  |  |  |  |  |  |  |  |
NA - not applicable |  |  |  |  |  |  |  |  |  |  |  |
(1) Weighted averages for loans individually evaluated were weighted by loan amounts. (2) Weighted averages for other real estate owned were weighted by OREO balances. (3) Weighted averages for mortgage servicing rights discount rate and prepayment rates are based on note rate tranches and voluntary constant prepayment rates.

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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 3. FAIR VALUE MEASUREMENTS - continued
The carrying values and fair values of our financial instruments at September 30, 2021 and December 31, 2020 are presented in the following tables:

| Carrying Value(1) |  | Fair Value Measurements at September 30, 2021
(dollars in thousands) |  | Total |  | Level 1 |  | Level 2 |  | Level 3
ASSETS |  |  |  |  |  |  |  |  |
Cash and due from banks, including interest-bearing deposits | $ | 934,377 |  |  | $ | 934,377 |  |  | $ | 934,377 |  |  | $ | — |  |  | $ | — |
Securities | 870,121 |  |  | 870,121 |  |  | 86,351 |  |  | 783,770 |  |  | — |
Loans held for sale | 4,303 |  |  | 4,303 |  |  | — |  |  | 4,303 |  |  | — |
Portfolio loans, net | 6,897,715 |  |  | 6,784,028 |  |  | — |  |  | — |  |  | 6,784,028 |
Collateral receivable | 43,193 |  |  | 43,193 |  |  | 43,193 |  |  | — |  |  | — |
Securities held in a deferred compensation plan | 9,320 |  |  | 9,320 |  |  | 9,320 |  |  | — |  |  | — |
Mortgage servicing rights | 7,015 |  |  | 7,015 |  |  | — |  |  | — |  |  | 7,015 |
Interest rate swaps | 42,177 |  |  | 42,177 |  |  | — |  |  | 42,177 |  |  | — |
Interest rate lock commitments | 813 |  |  | 813 |  |  | — |  |  | — |  |  | 813 |
Forward sale contracts | 101 |  |  | 101 |  |  | — |  |  | — |  |  | 101 |
LIABILITIES |  |  |  |  |  |  |  |  |
Deposits | $ | 7,945,119 |  |  | $ | 7,944,461 |  |  | $ | 6,743,851 |  |  | $ | 1,200,610 |  |  | $ | — |
Securities sold under repurchase agreements | 72,586 |  |  | 72,586 |  |  | 72,586 |  |  | — |  |  | — |
Short-term borrowings | — |  |  | — |  |  | — |  |  | — |  |  | — |
Long-term borrowings | 22,693 |  |  | 23,172 |  |  | 4,349 |  |  | 18,823 |  |  | — |
Junior subordinated debt securities | 64,128 |  |  | 64,128 |  |  | 64,128 |  |  | — |  |  | — |
Interest rate swaps | 42,554 |  |  | 42,554 |  |  | — |  |  | 42,554 |  |  | — |
(1) As reported in the Consolidated Balance Sheets |  |  |  |  |  |  |  |  |

| Carrying Value(1) |  | Fair Value Measurements at December 31, 2020
(dollars in thousands) |  | Total |  | Level 1 |  | Level 2 |  | Level 3
ASSETS |  |  |  |  |  |  |  |  |
Cash and due from banks, including interest-bearing deposits | $ | 229,666 |  |  | $ | 229,666 |  |  | $ | 229,666 |  |  | $ | — |  |  | $ | — |
Securities | 773,693 |  |  | 773,693 |  |  | 13,510 |  |  | 760,183 |  |  | — |
Loans held for sale | 18,528 |  |  | 18,528 |  |  | — |  |  | — |  |  | 18,528 |
Portfolio loans, net | 7,108,248 |  |  | 7,028,446 |  |  | — |  |  | — |  |  | 7,028,446 |
Collateral receivable | 77,936 |  |  | 77,936 |  |  | 77,936 |  |  | — |  |  | — |
Securities held in a deferred compensation plan | 6,794 |  |  | 6,794 |  |  | 6,794 |  |  | — |  |  | — |
Mortgage servicing rights | 4,976 |  |  | 4,976 |  |  | — |  |  | — |  |  | 4,976 |
Interest rate swaps | 78,319 |  |  | 78,319 |  |  | — |  |  | 78,319 |  |  | — |
Interest rate lock commitments | 2,900 |  |  | 2,900 |  |  | — |  |  | — |  |  | 2,900 |
LIABILITIES |  |  |  |  |  |  |  |  |
Deposits | $ | 7,420,538 |  |  | $ | 7,422,894 |  |  | $ | 6,033,075 |  |  | $ | 1,389,819 |  |  | $ | — |
Securities sold under repurchase agreements | 65,163 |  |  | 65,163 |  |  | 65,163 |  |  | — |  |  | — |
Short-term borrowings | 75,000 |  |  | 75,000 |  |  | 75,000 |  |  | — |  |  | — |
Long-term borrowings | 23,681 |  |  | 24,545 |  |  | 4,494 |  |  | 20,051 |  |  | — |
Junior subordinated debt securities | 64,083 |  |  | 64,083 |  |  | 64,083 |  |  | — |  |  | — |
Interest rate swaps | 79,033 |  |  | 79,033 |  |  | — |  |  | 79,033 |  |  | — |
Forward sale contracts | 385 |  |  | 385 |  |  | — |  |  | 385 |  |  | — |
(1) As reported in the Consolidated Balance Sheets |  |  |  |  |  |  |  |  |

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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 4. SECURITIES
The following table presents the fair values of our securities portfolio at the dates presented:

(dollars in thousands) | September 30, 2021 |  | December 31, 2020
Available-for-sale debt securities |  | $ | 868,994 |  |  |  | $ | 770,393 |
Marketable equity securities |  | 1,127 |  |  |  | 3,300 |
Total Securities |  | $ | 870,121 |  |  |  | $ | 773,693 |

Available-for-Sale Debt Securities
The following tables present the amortized cost and fair value of available-for-sale debt securities as of the dates presented:

| September 30, 2021 |  | December 31, 2020
(dollars in thousands) | Amortized Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Fair Value |  | Amortized Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Fair Value
U.S. Treasury securities |  | $ | 85,222 |  |  |  | $ | 326 |  |  |  | $ | (248) |  |  |  | $ | 85,300 |  |  |  | $ | 9,980 |  |  |  | $ | 302 |  |  |  | $ | — |  |  |  | $ | 10,282 |
Obligations of U.S. government corporations and agencies |  | 68,635 |  |  |  | 2,570 |  |  |  | — |  |  |  | 71,205 |  |  |  | 78,755 |  |  |  | 4,149 |  |  |  | — |  |  |  | 82,904 |
Collateralized mortgage obligations of U.S. government corporations and agencies |  | 206,325 |  |  |  | 3,858 |  |  |  | (1,198) |  |  |  | 208,985 |  |  |  | 202,975 |  |  |  | 6,410 |  |  |  | (89) |  |  |  | 209,296 |
Residential mortgage-backed securities of U.S. government corporations and agencies |  | 60,855 |  |  |  | 553 |  |  |  | (966) |  |  |  | 60,442 |  |  |  | 66,960 |  |  |  | 818 |  |  |  | — |  |  |  | 67,778 |
Commercial mortgage-backed securities of U.S. government corporations and agencies |  | 347,825 |  |  |  | 9,339 |  |  |  | (658) |  |  |  | 356,506 |  |  |  | 258,875 |  |  |  | 14,806 |  |  |  | — |  |  |  | 273,681 |
Corporate obligations |  | 500 |  |  |  | — |  |  |  | — |  |  |  | 500 |  |  |  | 2,021 |  |  |  | 5 |  |  |  | (1) |  |  |  | 2,025 |
Obligations of states and political subdivisions |  | 81,310 |  |  |  | 4,746 |  |  |  |  |  |  | 86,056 |  |  |  | 117,439 |  |  |  | 6,988 |  |  |  | — |  |  |  | 124,427 |
Total Available-for-Sale Debt Securities (1) |  | $ | 850,672 |  |  |  | $ | 21,392 |  |  |  | $ | (3,070) |  |  |  | $ | 868,994 |  |  |  | $ | 737,005 |  |  |  | $ | 33,478 |  |  |  | $ | (90) |  |  |  | $ | 770,393 |

(1) Excludes interest receivable of $3.2 million at September 30, 2021 and $3.1 million at December 31, 2020. Interest receivable is included in other assets in the consolidated balance sheets.
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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 4. SECURITIES – continued
The following tables present the fair value and the age of gross unrealized losses on available-for-sale debt securities by investment category as of the dates presented:

| September 30, 2021
| Less Than 12 Months |  | 12 Months or More |  | Total
(dollars in thousands) | Number of Securities |  | Fair Value |  | Unrealized Losses |  | Number of Securities |  | Fair Value |  | Unrealized Losses |  | Number of Securities |  | Fair Value |  | Unrealized Losses
U.S. Treasury securities | 4 |  | $ | 43,200 |  |  | $ | (248) |  |  | — |  | $ | — |  |  | $ | — |  |  | 4 |  | $ | 43,200 |  |  | $ | (248) |
Obligations of U.S. government corporations and agencies | — |  | — |  |  | — |  |  | — |  | — |  |  | — |  |  | — |  | — |  |  | — |
Collateralized mortgage obligations of U.S. government corporations and agencies | 7 |  | 88,290 |  |  | (1,198) |  |  | — |  | — |  |  | — |  |  | 7 |  | 88,290 |  |  | (1,198) |
Residential mortgage-backed securities of U.S. government corporations and agencies | 3 |  | 48,497 |  |  | (966) |  |  | — |  | — |  |  | — |  |  | 3 |  | 48,497 |  |  | (966) |
Commercial mortgage-backed securities of U.S. government corporations and agencies | 7 |  | 101,479 |  |  | (658) |  |  | — |  | — |  |  | — |  |  | 7 |  | 101,479 |  |  | (658) |
Corporate bonds | — |  | — |  |  | — |  |  | — |  | — |  |  | — |  |  | — |  | — |  |  | — |
Obligations of states and political subdivisions | 1 |  | 5,000 |  |  | — |  |  | — |  | — |  |  | — |  |  | 1 |  | 5,000 |  |  | — |
Total | 22 |  | $ | 286,466 |  |  | $ | (3,070) |  |  | — |  | $ | — |  |  | $ | — |  |  | 22 |  | $ | 286,466 |  |  | $ | (3,070) |

| December 31, 2020
| Less Than 12 Months |  | 12 Months or More |  | Total
(dollars in thousands) | Number of Securities |  | Fair Value |  | Unrealized Losses |  | Number of Securities |  | Fair Value |  | Unrealized Losses |  | Number of Securities |  | Fair Value |  | Unrealized Losses
U.S. Treasury securities | — |  | $ | — |  |  | $ | — |  |  | — |  | $ | — |  |  | $ | — |  |  | — |  | $ | — |  |  | $ | — |
Obligations of U.S. government corporations and agencies | — |  | — |  |  | — |  |  | — |  | — |  |  | — |  |  | — |  | — |  |  | — |
Collateralized mortgage obligations of U.S. government corporations and agencies | 2 |  | 35,697 |  |  | (89) |  |  | — |  | — |  |  | — |  |  | 2 |  | 35,697 |  |  | (89) |
Residential mortgage-backed securities of U.S. government corporations and agencies | — |  | — |  |  | — |  |  | — |  | — |  |  | — |  |  | — |  | — |  |  | — |
Commercial mortgage-backed securities of U.S. government corporations and agencies | — |  | — |  |  | — |  |  | — |  | — |  |  | — |  |  | — |  | — |  |  | — |
Corporate bonds | 1 |  | 499 |  |  | (1) |  |  | — |  | — |  |  | — |  |  | 1 |  | 499 |  |  | (1) |
Obligations of states and political subdivisions | — |  | — |  |  | — |  |  | — |  | — |  |  | — |  |  | — |  | — |  |  | — |
Total | 3 |  | $ | 36,196 |  |  | $ | (90) |  |  | — |  | $ | — |  |  | $ | — |  |  | 3 |  | $ | 36,196 |  |  | $ | (90) |

We evaluate securities with unrealized losses quarterly to determine if the decline in fair value has resulted from credit losses or other factors. There were 22 debt securities in an unrealized loss position at September 30, 2021 and 3 debt securities in an unrealized loss position at December 31, 2020. We do not intend to sell and it is more likely than not that we will not be required to sell the securities in an unrealized loss position before recovery of their amortized cost. The unrealized losses on the debt securities were attributable to changes in interest rates and not related to the credit quality of the issuers. All debt securities were determined to be investment grade and paying principal and interest according to the contractual terms of the security.
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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 4. SECURITIES – continued
The following table presents net unrealized gains and losses, net of tax, on available-for-sale debt securities included in accumulated other comprehensive income/(loss), for the periods presented:

| September 30, 2021 |  | December 31, 2020
(dollars in thousands) | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Net Unrealized Gains/(Losses) |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Net Unrealized Gains/(Losses)
Total unrealized gains/(losses) on available-for-sale debt securities | $ | 21,392 |  |  | $ | (3,070) |  |  | $ | 18,322 |  |  | $ | 33,478 |  |  | $ | (90) |  |  | $ | 33,388 |
Income tax (expense) benefit | (4,569) |  |  | 657 |  |  | (3,912) |  |  | (7,128) |  |  | 19 |  |  | (7,109) |
Net Unrealized Gains/(Losses), Net of Tax Included in Accumulated Other Comprehensive Income/(Loss) | $ | 16,823 |  |  | $ | (2,413) |  |  | $ | 14,410 |  |  | $ | 26,350 |  |  | $ | (71) |  |  | $ | 26,279 |

The amortized cost and fair value of available-for-sale debt securities at September 30, 2021 by contractual maturity are included in the table below. Actual maturities may differ from contractual maturities because issuers may have the right to call or prepay obligations with or without call or prepayment penalties.

| September 30, 2021
(dollars in thousands) | Amortized Cost |  | Fair Value
Obligations of the U.S. Treasury, U.S. government corporations and agencies, and obligations of states and political subdivisions |  |  |
Due in one year or less | $ | 30,428 |  |  | $ | 30,760 |
Due after one year through five years | 82,551 |  |  | 86,321 |
Due after five years through ten years | 101,252 |  |  | 102,563 |
Due after ten years | 20,936 |  |  | 22,917 |
Available-for-Sale Debt Securities With Fixed Maturities | 235,167 |  |  | 242,561 |
Debt Securities without a single maturity date |  |  |
Collateralized mortgage obligations of U.S. government corporations and agencies | 206,325 |  |  | 208,985 |
Residential mortgage-backed securities of U.S. government corporations and agencies | 60,855 |  |  | 60,442 |
Commercial mortgage-backed securities of U.S. government corporations and agencies | 347,825 |  |  | 356,506 |
Corporate Securities | 500 |  |  | 500 |
Total Available-for-Sale Debt Securities | $ | 850,672 |  |  | $ | 868,994 |

Debt securities with carrying values of $435.0 million at September 30, 2021 and $308.3 million at December 31, 2020 were pledged for various regulatory and legal requirements.
Marketable Equity Securities
The following table presents realized and unrealized net gains and losses for our marketable equity securities for the periods presented:

| Three Months Ended September 30, |  | Nine Months Ended September 30,
(dollars in thousands) | 2021 |  | 2020 |  | 2021 |  | 2020
Marketable Equity Securities |  |  |  |  |  |  |
Net market gains/(losses) recognized | $ | 31 |  |  | $ | 585 |  |  | $ | 175 |  |  | $ | (552) |
Less: Net gains recognized for equity securities sold | — |  |  | — |  |  | 29 |  |  | 142 |
Unrealized Gains/(Losses) on Equity Securities Still Held | $ | 31 |  |  | $ | 585 |  |  | $ | 146 |  |  | $ | (694) |

Total unrealized gains and losses on marketable equity securities recognized during the current period are included in other noninterest income on the Condensed Consolidated Statements of Comprehensive Income (Loss).
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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 5. LOANS AND LOANS HELD FOR SALE
Loans are presented net of unearned income of $14.5 million at September 30, 2021 and $16.0 million at December 31, 2020 and net of a discount related to purchase accounting fair value adjustments of $6.4 million at September 30, 2021 and $8.6 million at December 31, 2020. The following table presents loans as of the dates presented:

(dollars in thousands) | September 30, 2021 |  | December 31, 2020
Commercial |  |  |
Commercial real estate | $ | 3,225,863 |  |  | $ | 3,244,974 |
Commercial and industrial | 1,698,784 |  |  | 1,954,453 |
Commercial construction | 499,317 |  |  | 474,280 |
Total Commercial Loans | 5,423,964 |  |  | 5,673,707 |
Consumer |  |  |
Consumer real estate | 1,448,517 |  |  | 1,471,238 |
Other consumer | 97,606 |  |  | 80,915 |
Total Consumer Loans | 1,546,123 |  |  | 1,552,153 |
Total Portfolio Loans | 6,970,087 |  |  | 7,225,860 |
Loans held for sale | 4,303 |  |  | 18,528 |
Total Loans (1) | $ | 6,974,390 |  |  | $ | 7,244,388 |

(1) Excludes interest receivable of $19.1 million at September 30, 2021 and $24.7 million at December 31, 2020. Interest receivable is included in other assets in the consolidated balance sheets.
Commercial and industrial loans, or C&I, included $181.0 million of loans originated under the Paycheck Protection Program, or PPP, at September 30, 2021 compared to $465.0 million at December 31, 2020. On March 27, 2020, the Coronavirus Aid, Relief, and Economic Security, or CARES Act was signed into law. The CARES Act included the PPP, a program designed to aid small and medium sized businesses through federally guaranteed loans distributed through banks. PPP loans are forgivable, in whole or in part, if the proceeds are used for payroll and other permitted expenses in accordance with the requirements of the PPP. The loans are 100 percent guaranteed by the Small Business Administration, or SBA. These loans carry a fixed rate of 1.00 percent and a term of two years, or five years for loans approved by the SBA, on or after June 5, 2020. Payments are deferred for at least six months of the loan. The SBA pays us a processing fee ranging from 1 percent to 5 percent based on the size of the loan. Interest is accrued as earned and loan origination fees and direct costs are deferred and accreted or amortized into interest income over the life of the loan using the level yield method. When a PPP loan is paid off or forgiven by the SBA, the remaining unaccreted or unamortized net origination fees or costs will be immediately recognized into income.
At September 30, 2021, our business banking segment was $1.1 billion compared to $1.2 billion at December 31, 2020. $100.5 million of the business banking portfolio decline is due to the net change in business banking PPP loans. Business banking consists of commercial loans made to small businesses that are standard, non-complex products evaluated through a streamlined credit approval process that has been designed to maximize efficiency while maintaining high credit quality standards that meet small business market customers’ needs. Business banking consisted of $523.1 million of commercial real estate loans, $220.6 million of C&I loans of which $78.0 million are PPP loans, $13.4 million of commercial construction loans and $343.0 million of consumer real estate loans at September 30, 2021. At December 31, 2020 business banking consisted of $453.0 million of commercial real estate loans, $394.9 million of C&I loans of which $178.4 million are PPP loans, $8.2 million of commercial construction loans and $303.9 million of consumer real estate loans that have a commercial purpose. During the first quarter of 2021, $90.2 million of commercial loans and $23.2 million of consumer real estate loans were reclassified into the business banking segment.
We attempt to limit our exposure to credit risk by diversifying our loan portfolio by segment, geography, collateral and industry and actively managing concentrations. When concentrations exist in certain segments, we mitigate this risk by reviewing the relevant economic indicators and internal risk rating trends and through stress testing of the loans in these segments. Total commercial loans represented 77.8 percent of total portfolio loans at September 30, 2021 compared to 78.5 percent at December 31, 2020. Within our commercial portfolio, the CRE and commercial construction portfolios combined comprised $3.7 billion, or 68.7 percent, of total commercial loans at September 30, 2021 and $3.7 billion, or 65.6 percent, of total commercial loans at December 31, 2020 and 53.4 percent of total portfolio loans at September 30, 2021 and 51.5 percent at December 31, 2020.
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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 5. LOANS AND LOANS HELD FOR SALE - continued
We lend primarily in Pennsylvania and the contiguous states of Ohio, New York, West Virginia and Maryland. The majority of our commercial and consumer loans are made to businesses and individuals in this geography, resulting in a concentration. We believe our knowledge and familiarity with customers and conditions locally outweighs this geographic concentration risk. The conditions of the local and regional economies are monitored closely through publicly available data and information supplied by our customers. We also use subscription services for additional geographic and industry specific information. Our CRE and commercial construction portfolios have exposure outside of this geography of 5.0 percent of the combined portfolios and 2.7 percent of total portfolio loans at September 30, 2021. This compares to 5.9 percent of the combined portfolios and 3.0 percent of total portfolio loans at December 31, 2020.
We individually evaluate all substandard and nonaccrual commercial loans that have experienced a forbearance or change in terms agreement, and all substandard consumer and residential mortgage loans that entered into an agreement to modify their existing loan, to determine if they should be designated as troubled debt restructurings, or TDRs.
All TDRs will be reported as such for the remaining life of the loan, unless the restructuring agreement specifies an interest rate equal to or greater than the rate that would be accepted at the time of the restructuring for a new loan with comparable risk and it is fully expected that the remaining principal and interest will be collected according to the restructured agreement. TDRs can be returned to accruing status if the ultimate collectability of all contractual amounts due, according to the restructured agreement, is not in doubt and there is a period of a minimum of six months of satisfactory payment performance by the borrower either immediately before or after the restructuring.
The following tables summarize restructured loans as of the dates presented:

| September 30, 2021 |  | December 31, 2020
(dollars in thousands) | Performing TDRs |  | Nonperforming TDRs |  | Total TDRs |  | Performing TDRs |  | Nonperforming TDRs |  | Total TDRs
Commercial real estate | $ | 4,252 |  |  | $ | 11,093 |  |  | $ | 15,345 |  |  | $ | 14 |  |  | $ | 16,654 |  |  | $ | 16,668 |
Commercial and industrial | 1,762 |  |  | — |  |  | 1,762 |  |  | 7,090 |  |  | 9,885 |  |  | 16,975 |
Commercial construction | — |  |  | — |  |  | — |  |  | 3,267 |  |  | — |  |  | 3,267 |
Business banking | 1,647 |  |  | 1,492 |  |  | 3,139 |  |  | 1,503 |  |  | 430 |  |  | 1,933 |
Consumer real estate | 6,120 |  |  | 1,448 |  |  | 7,569 |  |  | 5,581 |  |  | 2,319 |  |  | 7,900 |
Other consumer | — |  |  | — |  |  | — |  |  | 5 |  |  | — |  |  | 5 |
Total | $ | 13,782 |  |  | $ | 14,033 |  |  | $ | 27,815 |  |  | $ | 17,460 |  |  | $ | 29,289 |  |  | $ | 46,748 |

There was one TDR for $0.1 million that returned to accruing status during the three months ended September 30, 2021 compared to two TDRs for a total of $0.1 million that returned to accruing status for the three months ended September 30, 2020. There were six TDRs for a total of $0.5 million that returned to accruing status during the nine months ended September 30, 2021 compared to three TDRs for a total of $22.7 million for the nine months ended September 30, 2020.
The following tables present the restructured loans by portfolio segment and by type of concession for the periods presented:

| Three Months Ended September 30, 2021
| Number of Contracts | Type of Modification | Total Post-Modification Outstanding Recorded Investment(2) | Total Pre-Modification Outstanding Recorded Investment(2)
(dollars in thousands) | Bankruptcy(1) | Other | Extend Maturity | Modify Rate | Modify Payments
Commercial real estate | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |
Commercial industrial | 2 |  | — |  | — |  | 341 |  | — |  | — |  | 341 |  | 342 |
Commercial construction | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |
Business banking | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |
Consumer real estate | 9 |  | 317 |  | — |  | 31 |  | — |  | — |  | 348 |  | 356 |
Other consumer | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |
Total | 11 |  | $ | 317 |  | $ | — |  | $ | 372 |  | $ | — |  | $ | — |  | $ | 689 |  | $ | 698 |
(1) Bankruptcy is consumer bankruptcy loans where the debt has been legally discharged through the bankruptcy court and not reaffirmed. (2) Excludes loans that were fully paid off or fully charged-off by period end. The pre-modification balance represents the balance outstanding prior to modification. The post-modification balance represents the outstanding balance at period end.

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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 5. LOANS AND LOANS HELD FOR SALE - continued

| Three Months Ended September 30, 2020
| Number of Contracts | Type of Modification | Total Post-Modification Outstanding Recorded Investment(2) | Total Pre-Modification Outstanding Recorded Investment(2)
(dollars in thousands) | Bankruptcy(1) | Other | Extend Maturity | Modify Rate | Modify Payments
Commercial real estate | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |
Commercial industrial | 2 |  | — |  | — |  | 3,735 |  | — |  | 287 |  | 4,022 |  | 4,021 |
Commercial construction | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |
Business banking | 1 |  | — |  | — |  | 171 |  | — |  | — |  | 171 |  | 333 |
Consumer real estate | 10 |  | 334 |  | — |  | 30 |  | — |  | — |  | 364 |  | 334 |
Other consumer | 1 |  | 4 |  | — |  | — |  | — |  | — |  | 4 |  | 5 |
Total | 14 |  | $ | 338 |  | $ | — |  | $ | 3,936 |  | $ | — |  | $ | 287 |  | $ | 4,561 |  | $ | 4,693 |
(1) Bankruptcy is consumer bankruptcy loans where the debt has been legally discharged through the bankruptcy court and not reaffirmed. (2) Excludes loans that were fully paid off or fully charged-off by period end. The pre-modification balance represents the balance outstanding prior to modification. The post-modification balance represents the outstanding balance at period end.

| Nine Months Ended September 30, 2021
| Number of Contracts | Type of Modification | Total Post-Modification Outstanding Recorded Investment(2) | Total Pre-Modification Outstanding Recorded Investment(2)
(dollars in thousands) | Bankruptcy(1) | Other | Extend Maturity | Modify Rate | Modify Payments
Commercial real estate | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |
Commercial industrial | 2 |  | — |  | — |  | 772 |  | — |  | 5,196 |  | 5,968 |  | 6,304 |
Commercial construction | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |
Business banking | 7 |  | — |  | 80 |  | 1,420 |  | — |  | — |  | 1,500 |  | 1,551 |
Consumer real estate | 20 |  | 866 |  |  | 31 |  |  | 147 |  | 1,045 |  | 1,064 |
Other consumer | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |
Total | 29 |  | $ | 866 |  | $ | 80 |  | $ | 2,223 |  | $ | — |  | $ | 5,343 |  | $ | 8,513 |  | $ | 8,919 |
(1) Bankruptcy is consumer bankruptcy loans where the debt has been legally discharged through the bankruptcy court and not reaffirmed. (2) Excludes loans that were fully paid off or fully charged-off by period end. The pre-modification balance represents the balance outstanding prior to modification. The post-modification balance represents the outstanding balance at period end.

| Nine Months Ended September 30, 2020
| Number of Contracts | Type of Modification | Total Post-Modification Outstanding Recorded Investment(2) | Total Pre-Modification Outstanding Recorded Investment(2)
(dollars in thousands) | Bankruptcy(1) | Other | Extend Maturity | Modify Rate | Modify Payments
Commercial real estate | 1 |  | $ | — |  | $ | — |  | $ | 2,210 |  | $ | — |  | $ | — |  | $ | 2,210 |  | $ | 2,210 |
Commercial industrial | 3 |  | — |  | — |  | 4,997 |  | — |  | 287 |  | 5,284 |  | 6,489 |
Commercial construction | 3 |  | — |  | — |  | 2,561 |  | — |  | — |  | 2,561 |  | 2,592 |
Business banking | 3 |  | — |  | — |  | 171 |  | — |  | 97 |  | 268 |  | 501 |
Consumer real estate | 23 |  | 1,052 |  | — |  | 206 |  | — |  | — |  | 1,258 |  | 1,237 |
Other consumer | 1 |  | 4 |  | — |  | — |  | — |  | — |  | 4 |  | 5 |
Total | 34 |  | $ | 1,056 |  | $ | — |  | $ | 10,145 |  | $ | — |  | $ | 384 |  | $ | 11,585 |  | $ | 13,034 |
(1) Bankruptcy is consumer bankruptcy loans where the debt has been legally discharged through the bankruptcy court and not reaffirmed. (2) Excludes loans that were fully paid off or fully charged-off by period end. The pre-modification balance represents the balance outstanding prior to modification. The post-modification balance represents the outstanding balance at period end.

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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 5. LOANS AND LOANS HELD FOR SALE - continued
In response to the coronavirus, or COVID-19, pandemic and its economic impact on our customers, we implemented a short-term modification program that complies with the CARES Act to provide temporary payment relief to those borrowers directly impacted by the pandemic who were not more than 30 days past due as of December 31, 2019. This program allows for a deferral of payments for 90 days and up to a maximum of 180 days for our commercial customers. The customer remains responsible for deferred payments along with any additional interest accrued during the deferral period. Under the applicable guidance, none of these loans were considered restructured as of September 30, 2021. We had 42 commercial loans that were modified totaling $58.9 million at September 30, 2021 compared to 52 commercial loans that were modified totaling $195.6 million at December 31, 2020.
As of September 30, 2021, we had 12 commitments to lend an additional $0.3 million on TDRs. Defaulted TDRs are defined as loans having a payment default of 90 days or more after the restructuring takes place. There were no TDRs that defaulted during the three and nine months ended September 30, 2021. There were no TDR's that defaulted during the three months ended September 30, 2020 and six TDRs that defaulted during the nine months ended September 30, 2020 for a total of $18.1 million that were restructured within the last 12 months prior to defaulting.
The following table is a summary of nonperforming assets as of the dates presented:

| Nonperforming Assets
(dollars in thousands) | September 30, 2021 |  | December 31, 2020
Nonperforming Assets |  |  |  |  |
Nonaccrual loans |  | $ | 97,279 |  |  |  | $ | 117,485 |
Nonaccrual TDRs |  | 14,033 |  |  |  | 29,289 |
Total Nonaccrual Loans(1) |  | 111,312 |  |  |  | 146,774 |
OREO |  | 13,370 |  |  |  | 2,155 |
Total Nonperforming Assets |  | $ | 124,682 |  |  |  | $ | 148,929 |
(1) Included in nonperforming commercial loans is $1.7 million of loans held for sale.

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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 6. ALLOWANCE FOR CREDIT LOSSES
We maintain an ACL at a level determined to be adequate to absorb estimated expected credit losses within the loan portfolio over the contractual life of an instrument that considers our historical loss experience, current conditions and forecasts of future economic conditions as of the balance sheet date. We develop and document a systematic ACL methodology based on the following portfolio segments: 1) Commercial Real Estate, or CRE, 2) Commercial and Industrial, or C&I, 3) Commercial Construction, 4) Business Banking, 5) Consumer Real Estate and 6) Other Consumer.
The following are key risks within each portfolio segment:
CRE—Loans secured by commercial purpose real estate, including both owner-occupied properties and investment properties for various purposes such as hotels, retail, multifamily and health care. Operations of the individual projects and global cash flows of the debtors are the primary sources of repayment for these loans. The condition of the local economy is an important indicator of risk, but there are also more specific risks depending on the collateral type and the business prospects of the lessee, if the project is not owner-occupied.
C&I—Loans made to operating companies or manufacturers for the purpose of production, operating capacity, accounts receivable, inventory or equipment financing. Cash flow from the operations of the company is the primary source of repayment for these loans. The condition of the local economy is an important indicator of risk, but there are also more specific risks depending on the industry of the company. Collateral for these types of loans often does not have sufficient value in a distressed or liquidation scenario to satisfy the outstanding debt.
Commercial Construction—Loans made to finance construction of buildings or other structures, as well as to finance the acquisition and development of raw land for various purposes. While the risk of these loans is generally confined to the construction/development period, if there are problems, the project may not be completed, and as such, may not provide sufficient cash flow on its own to service the debt or have sufficient value in a liquidation to cover the outstanding principal. The condition of the local economy is an important indicator of risk, but there are also more specific risks depending on the type of project and the experience and resources of the developer.
Business Banking—Commercial purpose loans made to small businesses that are standard, non-complex products evaluated through a streamlined credit approval process that has been designed to maximize efficiency while maintaining high credit quality standards that meet small business market customers’ needs. The business banking portfolio is monitored by utilizing a standard and closely managed process focusing on behavioral and performance criteria. The condition of the local economy is an important indicator of risk, but there are also more specific risks depending on the collateral type and business.
Consumer Real Estate—Loans secured by first and second liens such as home equity loans, home equity lines of credit and 1-4 family residential mortgages, including purchase money mortgages. The primary source of repayment for these loans is the income and assets of the borrower. The condition of the local economy, in particular the unemployment rate, is an important indicator of risk for this segment. The state of the local housing market can also have a significant impact on this segment because low demand and/or declining home values can limit the ability of borrowers to sell a property and satisfy the debt.
Other Consumer—Loans made to individuals that may be secured by assets other than 1-4 family residences, as well as unsecured loans. This segment includes auto loans, unsecured loans and lines. The primary source of repayment for these loans is the income and assets of the borrower. The condition of the local economy, in particular the unemployment rate, is an important indicator of risk for this segment. The value of the collateral, if there is any, is less likely to be a source of repayment due to less certain collateral values.
Management monitors various credit quality indicators for the commercial, business banking and consumer loan portfolios, including changes in risk ratings, nonperforming status and delinquency on a monthly basis.
We monitor the commercial loan portfolio through an internal risk rating system. Loan risk ratings are assigned based upon the creditworthiness of the borrower and are reviewed on an ongoing basis according to our internal policies. Loans within the pass rating generally have a lower risk of loss than loans risk rated as special mention or substandard.
Our risk ratings are consistent with regulatory guidance and are as follows:
Pass—The loan is currently performing and is of high quality.
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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 6. ALLOWANCE FOR CREDIT LOSSES – continued
Special Mention—A special mention loan has potential weaknesses that warrant management’s close attention. If left uncorrected, these potential weaknesses may result in deterioration of the repayment prospects or in the strength of our credit position at some future date.
Substandard—A substandard loan is not adequately protected by the net worth and/or paying capacity of the borrower or by the collateral pledged, if any. Substandard loans have a well-defined weakness or weaknesses that jeopardize the liquidation of the debt. These loans are characterized by the distinct possibility that we will sustain some loss if the deficiencies are not corrected.
Doubtful—Loans classified doubtful have all the weaknesses inherent in those classified substandard with the added characteristic that the weaknesses make collection or liquidation in full, on the basis of currently known facts, conditions, and values, highly questionable and improbable.
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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 6. ALLOWANCE FOR CREDIT LOSSES – continued
The following tables presents loan balances by year of origination and internally assigned risk rating for our portfolio segments as of the dates presented:

| September 30, 2021
| Risk Rating
(dollars in thousands) | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 and Prior | Revolving | Revolving-Term | Total
Commercial real estate |  |  |  |  |  |  |  |  |
Pass | $ | 255,876 |  | $ | 323,514 |  | $ | 443,487 |  | $ | 341,387 |  | $ | 224,258 |  | $ | 716,460 |  | $ | 42,326 |  | — |  | $ | 2,347,308 |
Special mention | — |  | 1,368 |  | 32,780 |  | 4,422 |  | 38,966 |  | 97,322 |  | — |  |  | 174,858 |
Substandard | — |  | 445 |  | 16,812 |  | 19,320 |  | 18,673 |  | 123,332 |  | 1,500 |  |  | 180,082 |
Doubtful | — |  | — |  | 532 |  | — |  | — |  | — |  | — |  | — |  | 532 |
Total commercial real estate | 255,876 |  | 325,327 |  | 493,611 |  | 365,129 |  | 281,897 |  | 937,114 |  | 43,826 |  | — |  | 2,702,780 |
Commercial and industrial |  |  |  |  |  |  |  |  |
Pass | 401,200 |  | 156,589 |  | 145,923 |  | 98,137 |  | 43,019 |  | 133,945 |  | 428,398 |  | — |  | 1,407,211 |
Special mention | 49 |  | 2,927 |  | 1,283 |  | 3,166 |  | 72 |  | 1,934 |  | 10,667 |  |  | 20,098 |
Substandard | 5,196 |  | — |  | 19,180 |  | 1,374 |  | 5,258 |  | 5,532 |  | 5,017 |  |  | 41,557 |
Doubtful | — |  | — |  | 9,332 |  | — |  | — |  | — |  | — |  | — |  | 9,332 |
Total commercial and industrial | 406,445 |  | 159,516 |  | 175,718 |  | 102,677 |  | 48,349 |  | 141,411 |  | 444,082 |  |  | 1,478,198 |
Commercial construction |  |  |  |  |  |  |  |  |
Pass | 100,774 |  | 134,440 |  | 172,508 |  | 33,903 |  | 996 |  | 4,298 |  | 21,714 |  | — |  | 468,633 |
Special mention | — |  | — |  | — |  | — |  | — |  | 4,491 |  | — |  |  | 4,491 |
Substandard | — |  | 2,149 |  | 7,416 |  | — |  | — |  | 3,235 |  | — |  |  | 12,800 |
Doubtful | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |
Total commercial construction | 100,774 |  | 136,589 |  | 179,924 |  | 33,903 |  | 996 |  | 12,024 |  | 21,714 |  |  | 485,924 |
Business banking |  |  |  |  |  |  |  |  |
Pass | 173,154 |  | 114,831 |  | 152,423 |  | 117,529 |  | 81,934 |  | 316,445 |  | 103,162 |  | 450 |  | 1,059,928 |
Special mention | 113 |  | 153 |  | 890 |  | 1,406 |  | 935 |  | 6,265 |  | 199 |  | 121 |  | 10,082 |
Substandard | 46 |  | 71 |  | 1,720 |  | 3,292 |  | 2,036 |  | 21,337 |  | 978 |  | 635 |  | 30,115 |
Doubtful | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |
Total business banking | 173,313 |  | 115,055 |  | 155,033 |  | 122,227 |  | 84,905 |  | 344,047 |  | 104,339 |  | 1,206 |  | 1,100,125 |
Consumer real estate |  |  |  |  |  |  |  |  |
Pass | 89,026 |  | 107,534 |  | 94,583 |  | 58,622 |  | 42,789 |  | 242,252 |  | 435,213 |  | 23,088 |  | 1,093,107 |
Special mention | — |  | — |  | — |  | — |  | — |  | 2,163 |  | — |  |  | 2,163 |
Substandard | — |  | — |  | 208 |  | 1,765 |  | 1,368 |  | 4,868 |  | 709 |  | 1,290 |  | 10,208 |
Doubtful | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |
Total consumer real estate | 89,026 |  | 107,534 |  | 94,791 |  | 60,387 |  | 44,157 |  | 249,283 |  | 435,922 |  | 24,378 |  | 1,105,478 |
Other consumer |  |  |  |  |  |  |  |  |
Pass | 9,833 |  | 10,852 |  | 8,470 |  | 3,852 |  | 1,442 |  | 2,888 |  | 50,725 |  | 1,113 |  | 89,175 |
Special mention | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |
Substandard | — |  | 52 |  | 105 |  | 150 |  | 368 |  | 5,930 |  | 255 |  | 1,547 |  | 8,407 |
Doubtful | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |
Total other consumer | 9,833 |  | 10,904 |  | 8,575 |  | 4,002 |  | 1,810 |  | 8,818 |  | 50,980 |  | 2,660 |  | 97,582 |
Pass | 1,029,863 |  | 847,760 |  | 1,017,394 |  | 653,430 |  | 394,438 |  | 1,416,288 |  | 1,081,538 |  | 24,651 |  | 6,465,362 |
Special mention | 162 |  | 4,448 |  | 34,953 |  | 8,994 |  | 39,973 |  | 112,175 |  | 10,866 |  | 121 |  | 211,692 |
Substandard | 5,242 |  | 2,717 |  | 45,441 |  | 25,901 |  | 27,703 |  | 164,234 |  | 8,459 |  | 3,472 |  | 283,169 |
Doubtful | — |  | — |  | 9,864 |  | — |  | — |  | — |  | — |  | — |  | 9,864 |
Total | $ | 1,035,267 |  | $ | 854,925 |  | $ | 1,107,652 |  | $ | 688,325 |  | $ | 462,114 |  | $ | 1,692,697 |  | $ | 1,100,863 |  | $ | 28,244 |  | $ | 6,970,087 |

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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 6. ALLOWANCE FOR CREDIT LOSSES – continued

| December 31, 2020
| Risk Rating
(dollars in thousands) | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 and Prior | Revolving | Revolving-Term | Total
Commercial real estate |  |  |  |  |  |  |  |  |
Pass | $ | 334,086 |  | $ | 422,800 |  | $ | 394,963 |  | $ | 277,724 |  | $ | 307,321 |  | $ | 615,217 |  | $ | 46,330 |  | $ | — |  | $ | 2,398,441 |
Special mention | — |  | 35,499 |  | 10,200 |  | 22,502 |  | 55,174 |  | 75,022 |  | — |  | — |  | 198,397 |
Substandard | — |  | 17,259 |  | 12,781 |  | 19,914 |  | 50,700 |  | 83,792 |  | 1,500 |  | — |  | 185,946 |
Doubtful | — |  | 645 |  | — |  | — |  | 1,989 |  | 6,529 |  | — |  | — |  | 9,163 |
Total commercial real estate | 334,086 |  | 476,203 |  | 417,944 |  | 320,140 |  | 415,184 |  | 780,560 |  | 47,830 |  | — |  | 2,791,947 |
Commercial and industrial |  |  |  |  |  |  |  |  |
Pass | 454,131 |  | 199,453 |  | 140,049 |  | 68,607 |  | 27,645 |  | 206,782 |  | 383,082 |  | — |  | 1,479,749 |
Special mention | 3,697 |  | 8,211 |  | 2,628 |  | 697 |  | 768 |  | 1,046 |  | 23,527 |  | — |  | 40,574 |
Substandard | — |  | 7,793 |  | 2,613 |  | 8,544 |  | 75 |  | 13,781 |  | 2,022 |  | — |  | 34,828 |
Doubtful | — |  | — |  | — |  | 4,401 |  | — |  | — |  | — |  | — |  | 4,401 |
Total commercial and industrial | 457,828 |  | 215,457 |  | 145,290 |  | 82,249 |  | 28,488 |  | 221,609 |  | 408,631 |  | — |  | 1,559,552 |
Commercial construction |  |  |  |  |  |  |  |  |
Pass | 131,235 |  | 224,794 |  | 59,649 |  | 2,420 |  | 6,346 |  | 4,555 |  | 12,778 |  | — |  | 441,777 |
Special mention | 1,578 |  | 2,533 |  | 3,886 |  | — |  | — |  | 8,593 |  | — |  | — |  | 16,590 |
Substandard | — |  | 3,580 |  | — |  | 501 |  | — |  | 3,629 |  | — |  | — |  | 7,710 |
Doubtful | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |
Total commercial construction | 132,813 |  | 230,907 |  | 63,535 |  | 2,921 |  | 6,346 |  | 16,777 |  | 12,778 |  | — |  | 466,077 |
Business banking |  |  |  |  |  |  |  |  |
Pass | 296,254 |  | 154,335 |  | 123,207 |  | 86,552 |  | 77,238 |  | 266,042 |  | 103,571 |  | 291 |  | 1,107,490 |
Special mention | — |  | 1,060 |  | 1,147 |  | 1,602 |  | 1,084 |  | 6,866 |  | 637 |  | 123 |  | 12,519 |
Substandard | 103 |  | 1,078 |  | 3,896 |  | 3,209 |  | 3,880 |  | 25,871 |  | 1,341 |  | 680 |  | 40,058 |
Doubtful | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |
Total business banking | 296,357 |  | 156,473 |  | 128,250 |  | 91,363 |  | 82,202 |  | 298,779 |  | 105,549 |  | 1,094 |  | 1,160,067 |
Consumer real estate |  |  |  |  |  |  |  |  |
Pass | 120,736 |  | 122,171 |  | 67,700 |  | 63,653 |  | 73,805 |  | 243,939 |  | 438,888 |  | 22,667 |  | 1,153,559 |
Special mention | — |  | — |  | 1,489 |  | — |  | — |  | 150 |  | 132 |  | — |  | 1,771 |
Substandard | — |  | 373 |  | 742 |  | 1,480 |  | 2,449 |  | 6,958 |  | — |  | — |  | 12,002 |
Doubtful | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |
Total consumer real estate | 120,736 |  | 122,544 |  | 69,931 |  | 65,133 |  | 76,254 |  | 251,047 |  | 439,020 |  | 22,667 |  | 1,167,332 |
Other consumer |  |  |  |  |  |  |  |  |
Pass | 18,849 |  | 13,162 |  | 6,784 |  | 3,395 |  | 2,082 |  | 687 |  | 26,647 |  | 2,767 |  | 74,373 |
Special mention | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |
Substandard | 15 |  | — |  | — |  | — |  | — |  | 3,367 |  | 744 |  | 2,386 |  | 6,512 |
Doubtful | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |  | — |
Total other consumer | 18,864 |  | 13,162 |  | 6,784 |  | 3,395 |  | 2,082 |  | 4,054 |  | 27,391 |  | 5,153 |  | 80,885 |
Pass | 1,355,292 |  | 1,136,716 |  | 792,352 |  | 502,350 |  | 494,436 |  | 1,337,222 |  | 1,011,297 |  | 25,724 |  | 6,655,389 |
Special Mention | 5,274 |  | 47,302 |  | 19,350 |  | 24,802 |  | 57,026 |  | 91,677 |  | 24,296 |  | 124 |  | 269,851 |
Substandard | 118 |  | 30,083 |  | 20,032 |  | 33,648 |  | 57,105 |  | 137,398 |  | 5,606 |  | 3,066 |  | 287,056 |
Doubtful | — |  | 645 |  | — |  | 4,401 |  | 1,989 |  | 6,529 |  | — |  | — |  | 13,564 |
Total | $ | 1,360,684 |  | $ | 1,214,746 |  | $ | 831,734 |  | $ | 565,201 |  | $ | 610,556 |  | $ | 1,572,826 |  | $ | 1,041,199 |  | $ | 28,914 |  | $ | 7,225,860 |

We monitor the delinquent status of the commercial and consumer portfolios on a monthly basis. Loans are considered nonperforming when interest and principal are 90 days or more past due or management has determined that a material deterioration in the borrower’s financial condition exists. The risk of loss is generally highest for nonperforming loans.
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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 6. ALLOWANCE FOR CREDIT LOSSES – continued
The following tables presents loan balances by year of origination and performing and nonperforming status for our portfolio segments as of September 30, 2021 and December 31, 2020:

| September 30, 2021
(dollars in thousands) | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 and Prior | Revolving | Revolving-Term | Total
Commercial real estate |  |  |  |  |  |  |  |  |
Performing | $ | 255,876 |  | $ | 325,327 |  | $ | 477,766 |  | $ | 362,382 |  | $ | 275,458 |  | $ | 907,348 |  | $ | 43,826 |  | $ | — |  | $ | 2,647,983 |
Nonperforming | — |  | — |  | 15,845 |  | 2,747 |  | 6,439 |  | 29,766 |  | — |  | — |  | 54,797 |
Total commercial real estate | 255,876 |  | 325,327 |  | 493,611 |  | 365,129 |  | 281,897 |  | 937,114 |  | 43,826 |  | — |  | 2,702,780 |
Commercial and industrial |  |  |  |  |  |  |  |  |
Performing | 401,249 |  | 159,516 |  | 153,731 |  | 102,310 |  | 44,963 |  | 141,201 |  | 441,319 |  | — |  | 1,444,289 |
Nonperforming | 5,196 |  |  | 21,987 |  | 367 |  | 3,386 |  | 210 |  | 2,763 |  | — |  | 33,909 |
Total commercial and industrial | 406,445 |  | 159,516 |  | 175,718 |  | 102,677 |  | 48,349 |  | 141,411 |  | 444,082 |  |  | 1,478,198 |
Commercial construction |  |  |  |  |  |  |  |  |
Performing | 100,774 |  | 136,589 |  | 176,567 |  | 33,903 |  | 996 |  | 11,328 |  | 21,714 |  | — |  | 481,871 |
Nonperforming | — |  | — |  | 3,357 |  | — |  | — |  | 696 |  | — |  | — |  | 4,053 |
Total commercial construction | 100,774 |  | 136,589 |  | 179,924 |  | 33,903 |  | 996 |  | 12,024 |  | 21,714 |  |  | 485,924 |
Business banking |  |  |  |  |  |  |  |  |
Performing | 173,267 |  | 115,055 |  | 154,639 |  | 120,811 |  | 84,187 |  | 336,486 |  | 104,310 |  | 1,149 |  | 1,089,904 |
Nonperforming | 46 |  | — |  | 394 |  | 1,416 |  | 718 |  | 7,561 |  | 29 |  | 57 |  | 10,221 |
Total business banking | 173,313 |  | 115,055 |  | 155,033 |  | 122,227 |  | 84,905 |  | 344,047 |  | 104,339 |  | 1,206 |  | 1,100,125 |
Consumer real estate |  |  |  |  |  |  |  |  |
Performing | 89,026 |  | 107,482 |  | 94,501 |  | 60,140 |  | 43,392 |  | 244,339 |  | 434,893 |  | 23,562 |  | 1,097,335 |
Nonperforming | — |  | 52 |  | 290 |  | 247 |  | 765 |  | 4,944 |  | 1,029 |  | 816 |  | 8,143 |
Total consumer real estate | 89,026 |  | 107,534 |  | 94,791 |  | 60,387 |  | 44,157 |  | 249,283 |  | 435,922 |  | 24,378 |  | 1,105,478 |
Other consumer |  |  |  |  |  |  |  |  |
Performing | 9,833 |  | 10,904 |  | 8,575 |  | 3,813 |  | 1,810 |  | 8,818 |  | 50,980 |  | 2,660 |  | 97,393 |
Nonperforming | — |  | — |  | — |  | 189 |  | — |  | — |  | — |  | — |  | 189 |
Total other consumer | 9,833 |  | 10,904 |  | 8,575 |  | 4,002 |  | 1,810 |  | 8,818 |  | 50,980 |  | 2,660 |  | 97,582 |
Performing | 1,030,025 |  | 854,873 |  | 1,065,779 |  | 683,359 |  | 450,806 |  | 1,649,520 |  | 1,097,042 |  | 27,371 |  | 6,858,775 |
Nonperforming(1) | 5,242 |  | 52 |  | 41,873 |  | 4,966 |  | 11,308 |  | 43,177 |  | 3,821 |  | 873 |  | 111,312 |
Total | $ | 1,035,267 |  | $ | 854,925 |  | $ | 1,107,652 |  | $ | 688,325 |  | $ | 462,114 |  | $ | 1,692,697 |  | $ | 1,100,863 |  | $ | 28,244 |  | $ | 6,970,087 |
(1) Included in nonperforming commercial loans is $1.7 million of loans held for sale with $0.3 million in 2010, $0.9 million in 2012 and $0.5 million in 2013.

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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 6. ALLOWANCE FOR CREDIT LOSSES – continued

| December 31, 2020
(dollars in thousands) | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 and Prior | Revolving | Revolving-Term | Total
Commercial real estate |  |  |  |  |  |  |  |  |
Performing | $ | 334,086 |  | $ | 459,799 |  | $ | 417,944 |  | $ | 313,465 |  | $ | 394,972 |  | $ | 722,781 |  | $ | 47,830 |  | $ | — |  | $ | 2,690,877 |
Nonperforming | — |  | 16,404 |  | — |  | 6,675 |  | 20,212 |  | 57,779 |  | — |  | — |  | 101,070 |
Total commercial real estate | 334,086 |  | 476,203 |  | 417,944 |  | 320,140 |  | 415,184 |  | 780,560 |  | 47,830 |  | — |  | 2,791,947 |
Commercial and industrial |  |  |  |  |  |  |  |  |
Performing | 457,828 |  | 214,144 |  | 143,706 |  | 69,411 |  | 28,426 |  | 220,701 |  | 408,351 |  | — |  | 1,542,567 |
Nonperforming | — |  | 1,313 |  | 1,584 |  | 12,838 |  | 62 |  | 908 |  | 280 |  | — |  | 16,985 |
Total commercial and industrial | 457,828 |  | 215,457 |  | 145,290 |  | 82,249 |  | 28,488 |  | 221,609 |  | 408,631 |  | — |  | 1,559,552 |
Commercial construction |  |  |  |  |  |  |  |  |
Performing | 132,813 |  | 230,907 |  | 63,535 |  | 2,921 |  | 6,346 |  | 16,393 |  | 12,778 |  | — |  | 465,693 |
Nonperforming | — |  | — |  | — |  | — |  | — |  | 384 |  | — |  | — |  | 384 |
Total commercial construction | 132,813 |  | 230,907 |  | 63,535 |  | 2,921 |  | 6,346 |  | 16,777 |  | 12,778 |  | — |  | 466,077 |
Business Banking |  |  |  |  |  |  |  |  |
Performing | 296,327 |  | 156,164 |  | 126,432 |  | 90,414 |  | 80,106 |  | 286,970 |  | 105,494 |  | 1,037 |  | 1,142,944 |
Nonperforming | 30 |  | 309 |  | 1,818 |  | 949 |  | 2,096 |  | 11,809 |  | 55 |  | 57 |  | 17,123 |
Total business banking | 296,357 |  | 156,473 |  | 128,250 |  | 91,363 |  | 82,202 |  | 298,779 |  | 105,549 |  | 1,094 |  | 1,160,067 |
Consumer real estate |  |  |  |  |  |  |  |  |
Performing | 120,736 |  | 122,315 |  | 69,225 |  | 63,647 |  | 74,690 |  | 245,331 |  | 438,701 |  | 21,571 |  | 1,156,216 |
Nonperforming | — |  | 229 |  | 706 |  | 1,486 |  | 1,564 |  | 5,716 |  | 319 |  | 1,096 |  | 11,116 |
Total consumer real estate | 120,736 |  | 122,544 |  | 69,931 |  | 65,133 |  | 76,254 |  | 251,047 |  | 439,020 |  | 22,667 |  | 1,167,332 |
Other consumer |  |  |  |  |  |  |  |  |
Performing | 18,864 |  | 13,162 |  | 6,784 |  | 3,395 |  | 2,082 |  | 3,958 |  | 27,391 |  | 5,153 |  | 80,789 |
Nonperforming | — |  | — |  | — |  | — |  | — |  | 96 |  | — |  | — |  | 96 |
Total other consumer | 18,864 |  | 13,162 |  | 6,784 |  | 3,395 |  | 2,082 |  | 4,054 |  | 27,391 |  | 5,153 |  | 80,885 |
Performing | 1,360,654 |  | 1,196,492 |  | 827,626 |  | 543,253 |  | 586,622 |  | 1,496,134 |  | 1,040,545 |  | 27,760 |  | 7,079,086 |
Nonperforming | 30 |  | 18,254 |  | 4,108 |  | 21,948 |  | 23,934 |  | 76,692 |  | 654 |  | 1,154 |  | 146,774 |
Total | $ | 1,360,684 |  | $ | 1,214,746 |  | $ | 831,734 |  | $ | 565,201 |  | $ | 610,556 |  | $ | 1,572,826 |  | $ | 1,041,199 |  | $ | 28,914 |  | $ | 7,225,860 |

The following tables present the age analysis of past due loans segregated by class of loans as of the dates presented:

| September 30, 2021
(dollars in thousands) | Current |  | 30-59 Days Past Due |  | 60-89 Days Past Due |  |  |  | Non - performing(2) |  | Total Past Due Loans |  | Total Loans
Commercial real estate | $ | 2,647,983 |  |  | $ | — |  |  | $ | — |  |  |  |  | $ | 54,797 |  |  | $ | 54,797 |  |  | 2,702,780 |
Commercial and industrial | 1,444,289 |  |  | — |  |  | — |  |  |  |  | 33,909 |  |  | 33,909 |  |  | 1,478,198 |
Commercial construction | 481,871 |  |  | — |  |  | — |  |  |  |  | 4,053 |  |  | 4,053 |  |  | 485,924 |
Business banking | 1,088,013 |  |  | 970 |  |  | 921 |  |  |  |  | 10,221 |  |  | 12,112 |  |  | 1,100,125 |
Consumer real estate | 1,095,557 |  |  | 833 |  |  | 945 |  |  |  |  | 8,143 |  |  | 9,921 |  |  | 1,105,478 |
Other consumer | 97,151 |  |  | 219 |  |  | 23 |  |  |  |  | 189 |  |  | 431 |  |  | 97,582 |
Total(1) | $ | 6,854,864 |  |  | $ | 2,022 |  |  | $ | 1,889 |  |  |  |  | $ | 111,312 |  |  | $ | 115,223 |  |  | $ | 6,970,087 |

(1) We had 42 loans that were modified totaling $58.9 million under the CARES Act at September 30, 2021. These customers were not considered past due as a result of their delayed payments. Upon exiting the loan modification deferral program, the measurement of loan delinquency will resume where it left off upon entry into the program. Due to the modifications, this delinquency table may not accurately reflect the credit risk associated with these loans.
(2) Included in nonperforming commercial loans is $1.7 million of loans held for sale.
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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 6. ALLOWANCE FOR CREDIT LOSSES – continued

| December 31, 2020
(dollars in thousands) | Current |  | 30-59 Days Past Due |  | 60-89 Days Past Due |  | Past Due 90+ Days Still Accruing (2) |  | Non - performing |  | Total Past Due Loans |  | Total Loans
Commercial real estate | $ | 2,690,877 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 101,070 |  |  | $ | 101,070 |  |  | $ | 2,791,947 |
Commercial and industrial | 1,542,567 |  |  | — |  |  | — |  |  | — |  |  | 16,985 |  |  | 16,985 |  |  | 1,559,552 |
Commercial construction | 462,094 |  |  | 19 |  |  | 3,580 |  |  | — |  |  | 384 |  |  | 3,983 |  |  | 466,077 |
Business banking | 1,140,581 |  |  | 1,614 |  |  | 379 |  |  | 371 |  |  | 17,122 |  |  | 19,486 |  |  | 1,160,067 |
Consumer real estate | 1,153,028 |  |  | 1,087 |  |  | 1,968 |  |  | 132 |  |  | 11,117 |  |  | 14,304 |  |  | 1,167,332 |
Other consumer | 80,583 |  |  | 168 |  |  | 37 |  |  | — |  |  | 96 |  |  | 302 |  |  | 80,885 |
Total(1) | $ | 7,069,730 |  |  | $ | 2,888 |  |  | $ | 5,965 |  |  | $ | 503 |  |  | $ | 146,774 |  |  | $ | 156,130 |  |  | $ | 7,225,860 |
(1) We had 52 loans that were modified totaling $195.6 million under the CARES Act at December 31, 2020. These customers were not considered past due as a result of their delayed payments. Upon exiting the loan modification deferral program, the measurement of loan delinquency will resume where it left off upon entry into the program. Due to the modification program, this delinquency table may not accurately reflect the credit risk associated with these loans. (2) Represents acquired loans that were recorded at fair value at the acquisition date and remain performing at December 31, 2020.

The following table presents loans on nonaccrual status by class of loan:

|  |  |  |  |  |  |  |  | September 30, 2021
| September 30, 2021 |  | For the three and nine months ended
(dollars in thousands) | Beginning of Period Nonaccrual |  | End of Period Nonaccrual(2) |  | Nonaccrual With No Related Allowance |  |  |  | Interest Income Recognized on Nonaccrual(1) |  | Interest Income Recognized on Nonaccrual(1)
Commercial real estate | $ | 101,070 |  |  | $ | 54,797 |  |  | $ | 47,730 |  |  |  |  | $ | 493 |  |  | $ | 556 |
Commercial and industrial | 16,985 |  |  | 33,909 |  |  | 12,566 |  |  |  |  | 6 |  |  | 88 |
Commercial construction | 384 |  |  | 4,053 |  |  | 3,357 |  |  |  |  | — |  |  | — |
Business banking | 17,122 |  |  | 10,221 |  |  | 1,492 |  |  |  |  | 57 |  |  | 333 |
Consumer real estate | 11,117 |  |  | 8,143 |  |  | — |  |  |  |  | 86 |  |  | 405 |
Other consumer | 96 |  |  | 189 |  |  | — |  |  |  |  | — |  |  | 1 |
Total | $ | 146,774 |  |  | $ | 111,312 |  |  | $ | 65,145 |  |  |  |  | $ | 642 |  |  | $ | 1,383 |

(1) Represents only cash payments received and applied to interest on nonaccrual loans.
(2) Included in nonperforming commercial loans is $1.7 million of loans held for sale.
.

|  |  |  |  |  |  |  |  | December 31, 2020
| December 31, 2020 |  | For the twelve months ended
(dollars in thousands) | Beginning of Period Nonaccrual |  | End of Period Nonaccrual |  | Nonaccrual With No Related Allowance |  | Past Due 90+ Days Still Accruing |  | Interest Income Recognized on Nonaccrual(1)
Commercial real estate | $ | 25,356 |  |  | $ | 101,070 |  |  | $ | 60,401 |  |  | $ | — |  |  | $ | 22 |
Commercial and industrial | 10,911 |  |  | 16,985 |  |  | 6,436 |  |  | — |  |  | 101 |
Commercial construction | 737 |  |  | 384 |  |  | 285 |  |  | — |  |  | — |
Business banking | 9,863 |  |  | 17,122 |  |  | 3,890 |  |  | 371 |  |  | 275 |
Consumer real estate | 6,063 |  |  | 11,117 |  |  | 398 |  |  | 132 |  |  | 423 |
Other consumer | 1,127 |  |  | 96 |  |  | — |  |  | — |  |  | 4 |
Total | $ | 54,057 |  |  | $ | 146,774 |  |  | $ | 71,410 |  |  | $ | 503 |  |  | $ | 826 |

(1) Represents only cash payments received and applied to interest on nonaccrual loans.
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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 6. ALLOWANCE FOR CREDIT LOSSES – continued
The following tables present collateral-dependent loans by class of loan as of the dates presented:

| September 30, 2021
| Type of Collateral
(dollars in thousands) | Real Estate |  | Business Assets |  | Investment/Cash |  | Other
Commercial real estate | $ | 51,006 |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Commercial and industrial | 272 |  |  | 13,738 |  |  | — |  |  | 21,730 |
Commercial construction | 6,057 |  |  | — |  |  | — |  |  | — |
Business banking | 1,714 |  |  | 1,424 |  |  | — |  |  | — |
Consumer real estate | — |  |  | — |  |  | — |  |  | — |
Total | $ | 59,049 |  |  | $ | 15,162 |  |  | $ | — |  |  | $ | 21,730 |

| December 31, 2020
| Type of Collateral
(dollars in thousands) | Real Estate |  | Business Assets |  | Investment/Cash |  | Other
Commercial real estate | $ | 100,450 |  | $ | — |  | $ | — |  | $ | —
Commercial and industrial | 1,040 |  | 15,080 |  | — |  | —
Commercial construction | 3,552 |  | — |  | — |  | —
Business banking | 3,085 |  | 1,619 |  | — |  | 689
Consumer real estate | 398 |  | — |  | — |  | —
Total | $ | 108,525 |  | $ | 16,699 |  | $ | — |  | $ | 689

The following tables present activity in the ACL for the periods presented:

| Three Months Ended September 30, 2021
(dollars in thousands) | Commercial Real Estate |  | Commercial and Industrial |  | Commercial Construction |  | Business Banking |  | Consumer Real Estate |  | Other Consumer |  | Total Loans
Allowance for credit losses on loans: |  |  |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of period | $ | 63,186 |  |  | $ | 14,426 |  |  | $ | 5,905 |  |  | $ | 14,756 |  |  | $ | 8,647 |  |  | $ | 2,717 |  |  | $ | 109,636 |
Provision for credit losses on loans(1) | (7,856) |  |  | 11,599 |  |  | 1,391 |  |  | (2,689) |  |  | (80) |  |  | (63) |  |  | 2,302 |
Charge-offs | (3,661) |  |  | (2) |  |  | (56) |  |  | (167) |  |  | (76) |  |  | (245) |  |  | (4,207) |
Recoveries | 1 |  |  | 216 |  |  | 2 |  |  | 241 |  |  | 33 |  |  | 123 |  |  | 616 |
Net (Charge-offs)/Recoveries | (3,660) |  |  | 214 |  |  | (54) |  |  | 74 |  |  | (43) |  |  | (122) |  |  | (3,591) |
Balance at End of Period | $ | 51,670 |  |  | $ | 26,239 |  |  | $ | 7,242 |  |  | $ | 12,141 |  |  | $ | 8,524 |  |  | $ | 2,532 |  |  | $ | 108,348 |
(1) Excludes unfunded commitments |  |  |  |  |  |  |  |  |  |  |  |  |

| Three Months Ended September 30, 2020
(dollars in thousands) | Commercial Real Estate |  | Commercial and Industrial |  | Commercial Construction |  | Business Banking |  | Consumer Real Estate |  | Other Consumer |  | Total Loans
Allowance for credit losses on loans: |  |  |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of period | $ | 57,730 |  |  | $ | 19,164 |  |  | $ | 8,874 |  |  | $ | 14,404 |  |  | $ | 11,585 |  |  | $ | 2,852 |  |  | $ | 114,609 |
Provision for credit losses on loans(1) | 23,839 |  |  | (4,155) |  |  | (1,617) |  |  | 2,072 |  |  | (797) |  |  | (40) |  |  | 19,302 |
Charge-offs | (10,187) |  |  | (1,196) |  |  | — |  |  | (1,748) |  |  | (252) |  |  | (284) |  |  | (13,667) |
Recoveries | 172 |  |  | 398 |  |  | 1 |  |  | 64 |  |  | 41 |  |  | 78 |  |  | 754 |
Net (Charge-offs)/Recoveries | (10,015) |  |  | (798) |  |  | 1 |  |  | (1,684) |  |  | (211) |  |  | (206) |  |  | (12,913) |
Balance at End of Period | $ | 71,554 |  |  | $ | 14,211 |  |  | $ | 7,258 |  |  | $ | 14,792 |  |  | $ | 10,577 |  |  | $ | 2,606 |  |  | $ | 120,998 |

(1) Excludes unfunded commitments
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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 6. ALLOWANCE FOR CREDIT LOSSES – continued

| Nine Months Ended September 30, 2021
(dollars in thousands) | Commercial Real Estate |  | Commercial and Industrial |  | Commercial Construction |  | Business Banking |  | Consumer Real Estate |  | Other Consumer |  | Total Loans
Allowance for credit losses on loans: |  |  |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of period | $ | 65,656 |  |  | $ | 16,100 |  |  | $ | 7,239 |  |  | $ | 15,917 |  |  | $ | 10,014 |  |  | $ | 2,686 |  |  | $ | 117,612 |
Provision for credit losses on loans(1) | (2,922) |  |  | 14,552 |  |  | 54 |  |  | (2,736) |  |  | (1,335) |  |  | (1) |  |  | 7,612 |
Charge-offs | $ | (12,030) |  |  | $ | (4,777) |  |  | $ | (56) |  |  | $ | (1,494) |  |  | $ | (422) |  |  | $ | (698) |  |  | $ | (19,477) |
Recoveries | 966 |  |  | 364 |  |  | 5 |  |  | 454 |  |  | 267 |  |  | 545 |  |  | 2,601 |
Net (Charge-offs)/Recoveries | (11,064) |  |  | (4,413) |  |  | (51) |  |  | (1,040) |  |  | (155) |  |  | (153) |  |  | (16,876) |
Balance at End of Period | $ | 51,670 |  |  | $ | 26,239 |  |  | $ | 7,242 |  |  | $ | 12,141 |  |  | $ | 8,524 |  |  | $ | 2,532 |  |  | $ | 108,348 |
(1) Excludes the provision for credit losses for unfunded commitments.

| Nine Months Ended September 30, 2020
(dollars in thousands) | Commercial Real Estate |  | Commercial and Industrial |  | Commercial Construction |  | Business Banking |  | Consumer Real Estate |  | Other Consumer |  | Total Loans
Allowance for credit losses on loans: |  |  |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of period | $ | 30,577 |  |  | $ | 15,681 |  |  | $ | 7,900 |  |  | $ | — |  |  | $ | 6,337 |  |  | $ | 1,729 |  |  | $ | 62,224 |
Impact of CECL adoption | 4,810 |  |  | 7,853 |  |  | (3,376) |  |  | 12,898 |  |  | 4,525 |  |  | 642 |  |  | 27,352 |
Provision for credit losses on loans(1) | 52,185 |  |  | 62,949 |  |  | 2,712 |  |  | 4,197 |  |  | 32 |  |  | 1,489 |  |  | 123,564 |
Charge-offs | (16,229) |  |  | (72,692) |  |  | — |  |  | (2,469) |  |  | (470) |  |  | (1,556) |  |  | (93,416) |
Recoveries | 211 |  |  | 420 |  |  | 22 |  |  | 166 |  |  | 153 |  |  | 302 |  |  | 1,274 |
Net (Charge-offs)/Recoveries | (16,018) |  |  | (72,272) |  |  | 22 |  |  | (2,303) |  |  | (317) |  |  | (1,254) |  |  | (92,142) |
Balance at End of Period | $ | 71,554 |  |  | $ | 14,211 |  |  | $ | 7,258 |  |  | $ | 14,792 |  |  | $ | 10,577 |  |  | $ | 2,606 |  |  | $ | 120,998 |
(1) Excludes unfunded commitments |  |  |  |  |  |  |  |  |  |  |  |  |

The adoption of ASU 2016-13 resulted in an increase to our ACL of $27.4 million on January 1, 2020. The increase included $8.2 million for S&T legacy loans and $9.3 million for acquired loans from the DNB merger. We also recorded a day one adjustment of $9.9 million primarily related to a C&I relationship that was charged off in the first quarter of 2020. We obtained information on the relationship subsequent to filing our December 31, 2019 Form 10-K, but before the end of the first quarter of 2020. The updated information supported a loss existed at January 1, 2020.
The provision for credit losses, which includes a provision for losses on loans and on unfunded commitments, is a charge to earnings to maintain the ACL at a level consistent with management's assessment of expected losses in the loan portfolio at the balance sheet date. The provision for credit losses decreased $14.1 million and $115.6 million to $3.4 million and $8.7 million for the three and nine months ended September 30, 2021 compared to $17.5 million and $124.3 million for the same periods in 2020. The provision for credit losses included $1.1 million and $1.5 million for the reserve for unfunded commitments for the three and nine months ended September 30, 2021.
The significant decrease in the provision for credit losses during the three and nine months ended September 30, 2021 was mainly due to the customer fraud in June of 2020 and an improved economic forecast in 2021 compared to 2020. Our economic forecast covers a period of two years and is driven primarily by national unemployment data. The forecasted national unemployment rate improved at September 30, 2021 compared to the same time in 2020.
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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 7. DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES
Interest Rate Swaps
In accordance with applicable accounting guidance for derivatives and hedging, all derivatives are recognized as either assets or liabilities on the balance sheet at fair value. Interest rate swaps are contracts in which a series of cash flows (fixed and variable) are exchanged over a prescribed period. The notional amounts on which the interest payments are based are not exchanged. These derivative positions relate to transactions in which we enter into an interest rate swap with a commercial customer while at the same time entering into an offsetting interest rate swap with another financial institution. In connection with each transaction, we agree to pay interest to the customer on a notional amount at a variable interest rate and receive interest from the customer on the same notional amount at a fixed rate. At the same time, we agree to pay another financial institution the same fixed interest rate on the same notional amount and receive the same variable interest rate on the same notional amount. The transaction allows our customer to effectively convert a variable rate loan to a fixed rate loan with us receiving a variable rate. These agreements could have floors or caps on the contracted interest rates.
Pursuant to our agreements with various financial institutions, we may receive collateral or may be required to post collateral based upon mark-to-market positions. Beyond unsecured threshold levels, collateral in the form of cash or securities may be made available to counterparties of interest rate swap transactions. Our current collateral requirements do not have a material effect on our cash flow or liquidity position.
Derivatives contain an element of credit risk, the possibility that we will incur a loss because a counterparty, which may be a financial institution or a customer, fails to meet its contractual obligations. All derivative contracts with financial institutions may be executed only with counterparties approved by our Asset and Liability Committee, or ALCO, and derivatives with customers may only be executed with customers within credit exposure limits approved by our Senior Loan Committee. Interest rate swaps are considered derivatives but are not accounted for using hedge accounting. As such, changes in the estimated fair value of the derivatives are recorded in current earnings and included in other noninterest income in the Condensed Consolidated Statements of Comprehensive Income (Loss).
Interest Rate Lock Commitments and Forward Sale Contracts
In the normal course of business, we sell originated mortgage loans into the secondary mortgage loan market. We also offer interest rate lock commitments to potential borrowers. The commitments are generally for a period of 60 days and guarantee a specified interest rate for a loan if underwriting standards are met, but the commitment does not obligate the potential borrower to close on the loan. Accordingly, some commitments expire prior to becoming loans. We may encounter pricing risks if interest rates increase significantly before the loan can be closed and sold. We may utilize forward sale contracts in order to mitigate this pricing risk. Whenever a customer desires these products, a mortgage originator quotes a secondary market rate guaranteed for that day by the investor. The rate lock is executed between the mortgagee and us and in turn a forward sale contract may be executed between us and the investor. Both the rate lock commitment and the corresponding forward sale contract for each customer are considered derivatives but are not accounted for using hedge accounting. As such, changes in the estimated fair value of the derivatives during the commitment period are recorded in current earnings and included in mortgage banking in the Condensed Consolidated Statements of Comprehensive Income (Loss).
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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 7. DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES – continued
The following table indicates the amounts representing the value of derivative assets and derivative liabilities as of the dates presented:

| Derivatives (included in Other Assets) |  | Derivatives (included in Other Liabilities)
(dollars in thousands) | September 30, 2021 |  | December 31, 2020 |  | September 30, 2021 |  | December 31, 2020
Derivatives not Designated as Hedging Instruments: |  |  |  |  |  |  |  |  |  |  |
Interest Rate Swap Contracts - Commercial Loans |  |  |  |  |  |  |  |  |  |  |
Fair value |  | $ | 42,177 |  |  |  | $ | 78,319 |  |  |  | $ | 42,554 |  |  |  | $ | 79,033 |
Notional amount |  | 998,385 |  |  |  | 983,638 |  |  |  | 998,385 |  |  |  | 983,638 |
Collateral posted |  | — |  |  |  | — |  |  |  | 43,190 |  |  |  | 77,930 |
Interest Rate Lock Commitments - Mortgage Loans |  |  |  |  |  |  |  |  |  |  |
Fair value |  | 812 |  |  |  | 2,900 |  |  |  | — |  |  |  | — |
Notional amount |  | 22,674 |  |  |  | 51,053 |  |  |  | — |  |  |  | — |
Forward Sale Contracts - Mortgage Loans |  |  |  |  |  |  |  |  |  |  |
Fair value |  | 101 |  |  |  | — |  |  |  | — |  |  |  | 385 |
Notional amount |  | $ | 18,915 |  |  |  | $ | — |  |  |  | $ | — |  |  |  | $ | 47,062 |

Presenting offsetting derivatives that are subject to legally enforceable netting arrangements with the same party is permitted. For example, we may have a derivative asset and a derivative liability with the same counterparty to a swap transaction and we are permitted to offset the asset position and the liability position resulting in a net presentation.
The following table indicates the gross amounts of commercial loan swap derivative assets and derivative liabilities, the amounts offset and the carrying values in the Consolidated Balance Sheets as of the dates presented:

| Derivatives (included in Other Assets) |  | Derivatives (included in Other Liabilities)
(dollars in thousands) | September 30, 2021 |  | December 31, 2020 |  | September 30, 2021 |  | December 31, 2020
Derivatives not Designated as Hedging Instruments: |  |  |  |  |  |  |  |  |  |  |
Gross amounts recognized |  | $ | 43,746 |  |  |  | $ | 82,655 |  |  |  | $ | 44,170 |  |  |  | $ | 82,626 |
Gross amounts offset |  | (1,569) |  |  |  | (4,336) |  |  |  | (1,616) |  |  |  | (3,593) |
Net Amounts Presented in the Consolidated Balance Sheets |  | 42,177 |  |  |  | 78,319 |  |  |  | 42,554 |  |  |  | 79,033 |
Gross amounts not offset(1) |  | — |  |  |  | — |  |  |  | (43,190) |  |  |  | (77,930) |
Net Amount |  | $ | 42,177 |  |  |  | $ | 78,319 |  |  |  | $ | (636) |  |  |  | $ | 1,103 |

(1) Amounts represent collateral posted for the periods presented and included in other assets on our Consolidated Balance Sheets.
The following table indicates the gain or loss recognized in income on derivatives for the periods presented:

| Three Months Ended September 30, |  | Nine Months Ended September 30,
(dollars in thousands) | 2021 |  | 2020 |  | 2021 |  | 2020
Derivatives not Designated as Hedging Instruments |  |  |  |  |  |  |  |  |  |  |
Interest rate swap contracts—commercial loans |  | $ | 22 |  |  |  | $ | (537) |  |  |  | $ | 337 |  |  |  | $ | (485) |
Interest rate lock commitments—mortgage loans |  | 192 |  |  |  | 86 |  |  |  | 712 |  |  |  | 2,877 |
Forward sale contracts—mortgage loans |  | (325) |  |  |  | 144 |  |  |  | (2,314) |  |  |  | (451) |
Total Derivatives (Loss)/Gain |  | $ | (111) |  |  |  | $ | (307) |  |  |  | $ | (1,265) |  |  |  | $ | 1,941 |

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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 8. COMMITMENTS AND CONTINGENCIES
Commitments
In the normal course of business, we offer off-balance sheet credit arrangements to enable our customers to meet their financing objectives. These instruments involve, to varying degrees, elements of credit and interest rate risk in excess of the amount recognized in the financial statements. Our exposure to credit loss, in the event the customer does not satisfy the terms of the agreement, equals the contractual amount of the obligation less the value of any collateral. We apply the same credit policies in making commitments and standby letters of credit that are used for the underwriting of loans to customers. Commitments generally have fixed expiration dates, annual renewals or other termination clauses and may require payment of a fee. Because many of the commitments are expected to expire without being drawn upon, the total commitment amounts do not necessarily represent future cash requirements.
Estimates of the fair value of these off-balance sheet items were not made because of the short-term nature of these arrangements and the credit standing of the counterparties.
The following table sets forth our commitments and letters of credit as of the dates presented:

(dollars in thousands) | September 30, 2021 |  | December 31, 2020 |
Commitments to extend credit |  | $ | 2,500,541 |  |  |  | $ | 2,185,752 |  |
Standby letters of credit |  | 90,250 |  |  |  | 89,095 |  |
Total |  | $ | 2,590,791 |  |  |  | $ | 2,274,847 |  |

Allowance for Credit Losses on Unfunded Loan Commitments
We maintain an allowance for credit losses on unfunded commercial lending commitments and letters of credit to provide for the risk of loss inherent in these arrangements. The allowance is computed using a methodology similar to that used to determine the allowance for credit losses for loans, modified to take into account the probability of a draw-down on the commitment. The provision for credit losses on unfunded loan commitments is included in the provision for credit losses on our Condensed Consolidated Statements of Comprehensive Income (Loss). The allowance for unfunded commitments is included in other liabilities in the Consolidated Balance Sheets.
The following table presents activity in the allowance for credit losses on unfunded loan commitments as of the dates presented:

| Three Months Ended September 30, |  | Nine Months Ended September 30,
(dollars in thousands) | 2021 |  | 2020 |  | 2021 |  | 2020
Balance at beginning of period |  | $ | 4,858 |  |  |  | $ | 7,004 |  |  |  | $ | 4,467 |  |  |  | $ | 3,112 |
Impact of adopting ASU 2016-13 at January 1, 2020 |  | — |  |  |  | — |  |  |  | — |  |  |  | 1,349 |
Balance after adoption of ASU 2016-13 |  | 4,858 |  |  |  | 7,004 |  |  |  | 4,467 |  |  |  | 4,461 |
Provision for credit losses |  | 1,085 |  |  |  | (1,816) |  |  |  | 1,476 |  |  |  | 727 |
Total |  | $ | 5,943 |  |  |  | $ | 5,188 |  |  |  | $ | 5,943 |  |  |  | $ | 5,188 |

Litigation
In the normal course of business, we are subject to various legal and administrative proceedings and claims. While any type of litigation contains a level of uncertainty, we believe that the outcome of such proceedings or claims pending will not have a material adverse effect on our consolidated financial position or results of operations.
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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 9. OTHER COMPREHENSIVE INCOME (LOSS)
The following table presents the change in components of other comprehensive income (loss) for the periods presented, net of tax effects.

| Three Months Ended September 30, 2021 |  | Three Months Ended September 30, 2020
(dollars in thousands) | Pre-Tax Amount |  | Tax (Expense) Benefit |  | Net of Tax Amount |  | Pre-Tax Amount |  | Tax Benefit (Expense) |  | Net of Tax Amount
Change in net unrealized gains/(losses) on debt securities available-for-sale |  | $ | (5,676) |  |  |  | $ | 1,211 |  |  |  | $ | (4,465) |  |  |  | $ | (882) |  |  |  | $ | 188 |  |  |  | $ | (694) |
Adjustment to funded status of employee benefit plans (1) |  | (215) |  |  |  | 46 |  |  |  | (169) |  |  |  | 1,163 |  |  |  | (248) |  |  |  | 915 |
Other Comprehensive Income |  | $ | (5,891) |  |  |  | $ | 1,257 |  |  |  | $ | (4,634) |  |  |  | $ | 281 |  |  |  | $ | (60) |  |  |  | $ | 221 |
(1) Pension settlement accounting was recognized during the periods ended September 30, 2021 resulting in a charge of $0.4 million for the three months ended September 30, 2021 immediately recognizing a portion of unrecognized actuarial loss and a remeasurement of our pension obligation.
| Nine Months Ended September 30, 2021 |  | Nine Months Ended September 30, 2020
(dollars in thousands) | Pre-Tax Amount |  | Tax (Expense) Benefit |  | Net of Tax Amount |  | Pre-Tax Amount |  | Tax (Expense) Benefit |  | Net of Tax Amount
Change in net unrealized gains/(losses) on available-for-sale debt securities |  | $ | (15,065) |  |  |  | $ | 3,215 |  |  |  | $ | (11,850) |  |  |  | $ | 24,883 |  |  |  | $ | (5,294) |  |  |  | $ | 19,589 |
Reclassification adjustment for net (gains)/losses on debt securities available-for-sale included in net income (1) |  | — |  |  |  | — |  |  |  | — |  |  |  | (142) |  |  |  | 30 |  |  |  | (112) |
Adjustment to funded status of employee benefit plans (1) |  | 2,351 |  |  |  | (501) |  |  |  | 1,850 |  |  |  | 2,092 |  |  |  | (446) |  |  |  | 1,646 |
Other Comprehensive (Loss)/Income |  | $ | (12,714) |  |  |  | $ | 2,714 |  |  |  | $ | (10,000) |  |  |  | $ | 26,833 |  |  |  | $ | (5,710) |  |  |  | $ | 21,123 |
(1) Pension settlement accounting was recognized during the periods ended September 30, 2021 resulting in a charge of $1.3 million for the nine months ended September 30, 2021 immediately recognizing a portion of unrecognized actuarial loss and a remeasurement of our pension obligation.

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S&T BANCORP, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS – continued
NOTE 10. EMPLOYEE BENEFITS
Our qualified and nonqualified defined benefit plans were amended to freeze benefit accruals for all persons entitled to benefits under the plans in 2016. We will continue recording pension expense related to these plans, primarily representing interest costs on the projected benefit obligation and amortization of actuarial losses accumulated in the plans, as well as income from expected investment returns on pension assets. Since the plans have been frozen, no service costs are included in net periodic pension expense.
The investment policy for S&T's defined benefit plan is 90 percent fixed income and 10 percent equity and cash. The expected long-term rate of return on plan assets is 2.42 percent as of September 30, 2021 compared to 3.45 percent for the same period in 2020.
We remeasured our pension obligation and recognized a pension settlement charge of $0.4 million and $1.3 million for the three and nine months ended September 30, 2021. A settlement charge is incurred when the aggregate amount of lump-sum distributions during the year is greater than the sum of the interest cost component of the annual net periodic pension cost.
The following table summarizes the components of net periodic pension cost for the periods presented:

| Three Months Ended September 30, |  | Nine Months Ended September 30,
(dollars in thousands) | 2021 |  | 2020 |  | 2021 |  | 2020
Components of Net Periodic Pension Cost |  |  |  |  |  |  |  |  |  |  |
Interest cost on projected benefit obligation |  | $ | 721 |  |  |  | $ | 905 |  |  |  | $ | 2,221 |  |  |  | $ | 2,686 |
Expected return on plan assets |  | (668) |  |  |  | (970) |  |  |  | (2,029) |  |  |  | (2,913) |
Net amortization |  | 246 |  |  |  | 411 |  |  |  | 792 |  |  |  | 1,180 |
Settlement Charge |  | 370 |  |  |  | 671 |  |  |  | 1,296 |  |  |  | 671 |
Net Periodic Pension Expense |  | $ | 669 |  |  |  | $ | 1,017 |  |  |  | $ | 2,280 |  |  |  | $ | 1,624 |

The components of net periodic pension expense are included in salaries and employee benefits on the Condensed Consolidated Statements of Comprehensive Income (Loss).
NOTE 11. SHARE REPURCHASE PLAN
On March 15, 2021, our Board of Directors authorized an extension of its $50 million share repurchase plan, which was set to expire March 31, 2021. This authorization extended the expiration date of the repurchase plan through March 31, 2022. The plan permits S&T to repurchase from time to time up to the previously authorized $50 million in aggregate value of shares of S&T's common stock, with $37.4 million of capacity remaining at September 30, 2021, through a combination of open market and privately negotiated repurchases. The specific timing, price and quantity of repurchases will be at the discretion of S&T and will depend on a variety of factors, including general market conditions, the trading price of common stock, legal and contractual requirements, applicable securities laws and S&T's financial performance. The repurchase plan does not obligate us to repurchase any particular number of shares. We expect to fund any repurchases from cash on hand and internally generated funds. Any share repurchases will not begin until permissible under applicable laws. During the three and nine months ended September 30, 2021, we had no repurchases. Repurchase activity was suspended in March of 2020 due to the impact of the COVID-19 pandemic. During the year ended December 31, 2020, we repurchased 411,430 common shares at a total cost of $12.6 million, or an average of $30.52 per share.
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S&T BANCORP, INC. AND SUBSIDIARIES
Item 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS
Management’s Discussion and Analysis of Financial Condition and Results of Operations, or MD&A, represents an overview of our consolidated results of operations and financial condition and highlights material changes in our financial condition and results of operations at and for the three and nine month periods ended September 30, 2021 and 2020. Our MD&A should be read in conjunction with our Consolidated Financial Statements and Notes. The results of operations reported in the accompanying Consolidated Financial Statements are not necessarily indicative of results to be expected in future periods.
Important Note Regarding Forward-Looking Statements
This quarterly report on Form 10-Q contains or incorporates statements that we believe are “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements generally relate to our financial condition, results of operations, plans, objectives, outlook for earnings, revenues, expenses, capital and liquidity levels and ratios, asset levels, asset quality, financial position, and other matters regarding or affecting S&T and its future business and operations. Forward-looking statements are typically identified by words or phrases such as “will likely result”, “expect”, “anticipate”, “estimate”, “forecast”, “project”, “intend”, “ believe”, “assume”, “strategy”, “trend”, “plan”, “outlook”, “outcome”, “continue”, “remain”, “potential”, “opportunity”, “comfortable”, “current”, “position”, “maintain”, “sustain”, “seek”, “achieve” and variations of such words and similar expressions, or future or conditional verbs such as will, would, should, could or may. Although we believe the assumptions upon which these forward-looking statements are based are reasonable, any of these assumptions could prove to be inaccurate and the forward-looking statements based on these assumptions could be incorrect. The matters discussed in these forward-looking statements are subject to various risks, uncertainties and other factors that could cause actual results and trends to differ materially from those made, projected, or implied in or by the forward-looking statements depending on a variety of uncertainties or other factors including, but not limited to: credit losses and the credit risk of our commercial and consumer loan products; changes in the level of charge-offs and changes in estimates of the adequacy of the allowance for credit losses; cyber-security concerns; rapid technological developments and changes; operational risks or risk management failures by us or critical third parties, including fraud risk; our ability to manage our reputational risks; sensitivity to the interest rate environment including a prolonged period of low interest rates, a rapid increase in interest rates or a change in the shape of the yield curve; a change in spreads on interest-earning assets and interest-bearing liabilities; the transition from LIBOR as a reference rate; regulatory supervision and oversight, including changes in regulatory capital requirements and our ability to address those requirements; unanticipated changes in our liquidity position; changes in accounting policies, practices, or guidance, for example, our adoption of CECL; legislation affecting the financial services industry as a whole, and S&T, in particular; the outcome of pending and future litigation and governmental proceedings; increasing price and product/service competition; the ability to continue to introduce competitive new products and services on a timely, cost-effective basis; managing our internal growth and acquisitions; the possibility that the anticipated benefits from acquisitions, including DNB, cannot be fully realized in a timely manner or at all, or that integrating the acquired operations will be more difficult, disruptive or costly than anticipated; containing costs and expenses; reliance on significant customer relationships; an interruption or cessation of an important service by a third-party provider; our ability to attract and retain talented executives and employees; our ability to successfully manage our CEO transition; general economic or business conditions, including the strength of regional economic conditions in our market area; the duration and severity of the coronavirus (“COVID-19”) pandemic, both in our principal area of operations and nationally, including the ultimate impact of the pandemic on the economy generally and on our operations, as well as compliance with any vaccine or testing mandate issued by the U.S. Department of Labor's occupational Safety and Health Administration ("OSHA") or any other government agency; our participation in the Paycheck Protection Program; deterioration of the housing market and reduced demand for mortgages; deterioration in the overall macroeconomic conditions or the state of the banking industry that could warrant further analysis of the carrying value of goodwill and could result in an adjustment to its carrying value resulting in a non-cash charge to net income; the stability of our core deposit base and access to contingency funding; re-emergence of turbulence in significant portions of the global financial and real estate markets that could impact our performance, both directly, by affecting our revenues and the value of our assets and liabilities, and indirectly, by affecting the economy generally and access to capital in the amounts, at the times and on the terms required to support our future businesses.
Many of these factors, as well as other factors, are described in our Annual Report on Form 10-K for the year ended December 31, 2020, including Part I, Item 1A-"Risk Factors" and any of our subsequent filings with the SEC. Forward-looking statements are based on beliefs and assumptions using information available at the time the statements are made. We caution you not to unduly rely on forward-looking statements because the assumptions, beliefs, expectations and projections about future events may, and often do, differ materially from actual results. Any forward-looking statement speaks only to the date on which it is made, and we undertake no obligation to update any forward-looking statement to reflect developments occurring after the statement is made.
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S&T BANCORP, INC. AND SUBSIDIARIES
Item 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS
Critical Accounting Policies and Estimates
Our critical accounting policies involving significant judgments and assumptions used in the preparation of the Consolidated Financial Statements as of September 30, 2021 remained unchanged from the disclosures presented in our Annual Report on Form 10-K for the year ended December 31, 2020 under Part II, Item 7 - “Management’s Discussion and Analysis of Financial Condition and Results of Operations”.
Overview
We are a bank holding company that is headquartered in Indiana, Pennsylvania with assets of $9.4 billion at September 30, 2021. We operate in five markets including Western Pennsylvania, Eastern Pennsylvania, Northeast Ohio, Central Ohio and Upstate New York. We provide a full range of financial services with retail and commercial banking products, cash management services, trust and brokerage services. Our common stock trades on the NASDAQ Global Select Market under the symbol “STBA”.
We earn revenue primarily from interest on loans and securities and fees charged for financial services provided to our customers. We incur expenses for the cost of deposits and other funding sources, provision for credit losses and other operating costs such as salaries and employee benefits, data processing, occupancy and tax expense.
Our mission is to become the financial services provider of choice within the markets that we serve which will enable us to be a high performing regional community bank. We strive to do this by delivering exceptional service and value. Our strategic plan follows a disciplined approach focused on organic growth, which includes both growth within our current footprint and through market expansion. We employ a geographic, market-based growth platform in order to drive organic growth. We acknowledge that each of our five markets are in different stages of development and that our market-based strategy will allow us to customize our approach to each market given its developmental stage and unique characteristics. We also actively evaluate acquisition opportunities that align with our strategic objectives as another source of growth. Our strategic plan includes a collaborative model that combines expertise from all areas of our business and focuses on satisfying each customer’s individual financial objectives. We continuously work to maintain and improve the efficiency of our different lines of business.
COVID-19 Update
The extent to which the COVID-19 pandemic may adversely impact our business depends on future developments, which remain highly uncertain and unpredictable. The pandemic has had, and we expect that it will continue to have, negative impacts on S&T’s commercial and consumer loan customers and the economy as a whole. The severity and length of the pandemic’s impact on S&T and the U.S. and global economies continue to be unknown. On September 9, 2021, President Biden announced that OSHA is developing a rule that will require all employers with 100 or more employees to ensure their workforce is fully vaccinated or require unvaccinated workers to produce a negative test result on at least a weekly basis before coming to work. As an employer with more than 100 employees, S&T will be required to comply with the rule. We are currently monitoring the requirements and evaluating any potential impact of this rulemaking.
As we navigate through the uncertainty resulting from the pandemic, our first priority remains the safety of both our employees and customers. Our financial performance continues to be negatively impacted in many ways due to the pandemic. We are closely monitoring our asset quality with a focus on the loan portfolios that have been significantly impacted by the pandemic, including our hotel portfolio. We did experience some improvement in our asset quality during the three and nine months ended September 30, 2021, but remain cautious given the current environment. Our balance sheet is asset sensitive resulting in our net interest income and net interest margin, or NIM, being negatively impacted in this low interest rate environment. Loan demand was challenging in the first half of 2021, but we have seen growth trends improving late in the second quarter and for the third quarter of 2021. Net interest income was favorably impacted by PPP loans which contributed $4.2 million and $14.2 million for the three and nine months ended September 30, 2021 to interest income.
Earnings Summary
We recognized net income of $27.6 million, or $0.70 per diluted share and $87.9 million, or $2.24 per diluted share for the three and nine months ended September 30, 2021 compared to a net income of $16.7 million, or $0.43 per diluted share and a net loss of $(3.1) million, or $(0.08) per diluted share for the same periods in 2020. The increase in net income for the three and nine months ended September 30, 2021 was primarily due to a significant decrease of $14.1 million and $115.2 million in our provision for credit losses compared to the same periods in 2020. The significant decrease in the provision for credit losses during the three and nine months ended September 30, 2021 was mainly due to a customer fraud in 2020 that resulted in a $58.7 million charge-off in June of 2020 as well as the impact of the COVID-19 pandemic that resulted in the need for a greater provision in 2020 compared to 2021 based on the relevant economic forecast.
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Item 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS
Net interest income decreased $0.6 million and $1.8 million to $68.7 million and $207.7 million for the three and nine months ended September 30, 2021 compared to $69.3 million and $209.5 million in 2020. The decrease in interest income was primarily due to lower average loan balances and the low rate interest environment compared to the same periods in 2020. Average loan balances decreased $480.7 million and $320.8 million for the three and nine months ended September 30, 2021 compared to the same periods in 2020. Our net interest margin on an FTE basis (non-GAAP) decreased to 3.14 percent and 3.25 percent for the three and nine months ended September 30, 2021 compared to 3.29 percent and 3.37 percent for the same periods in 2020 primarily due to lower short-term interest rates and higher interest bearing deposits with banks. Net interest margin is reconciled to net interest income adjusted to an FTE basis in the "Net Interest Income" section of this MD&A.
The provision for credit losses, which includes a provision for losses on loans and on unfunded commitments, decreased $14.1 million and $115.2 million to $3.4 million and $9.1 million for the three and nine months ended September 30, 2021 compared to $17.5 million and $124.3 million for the same periods in 2020. The significant decrease in the provision for credit losses during the nine months ended September 30, 2021 was mainly due to the customer fraud previously described above and an improved economic forecast in 2021. The decrease in the provision for credit losses during the three months ended September 30, 2021 was due to an improved economic forecast in 2021 compared to 2020.
Noninterest income decreased $0.6 million and increased $4.4 million for the three and nine months ended September 30, 2021 compared to the same periods in 2020. Debit and credit card and service charges on deposit accounts increased in both the three and nine months ended September 30, 2021 as customer activity has increased in the improving economic environment. Wealth management income increased in both periods due to higher assets under management from market appreciation and an increase in customer activity. Partially offsetting these increases was a decrease in commercial loan swap income due to lower activity as a result of the pandemic and interest rate environment.
Noninterest expense decreased $1.0 million to $47.2 million for the three months ended September 30, 2021 and increased $0.5 million to $138.6 million for the nine months ended September 30, 2021 compared to $48.2 million and $138.1 million for the same periods in 2020. The decrease in noninterest expense for the three months ended September 30, 2021 was mainly due to lower marketing, FDIC insurance and professional services and legal services compared to the prior period. The higher noninterest expense for the nine months ended September 30, 2021 was mainly due to an increase of salaries and employee benefits of $5.7 million offset by lower FDIC insurance, marketing and $2.3 million less of merger-related expenses.
The provision for income taxes increased $3.0 million and $26.3 million to $6.3 million and $20.6 million for the three and nine months ended September 30, 2021 compared to the same periods in 2020. The increase in income tax expense was primarily due to the increase in pretax income for both periods compared to the same periods in 2020. The increase in pretax income in the nine months ended September 30, 2021 was primarily due to the loss incurred from the customer fraud in the same period in 2020 which resulted in a pretax loss and tax benefit. The increase in pretax income for the three months ended September 30, 2021, was primarily due to the reduced provision for credit losses as a result of the improved economic forecast. Our effective tax rate was 18.7 percent and 19.0 percent for the three and nine months ended September 30, 2021 compared to 16.6 percent and (64.5) percent for the same period in 2020. The change in our effective tax rate for the nine months ended September 30, 2021 was primarily due to the increase in pretax income compared to 2020.
Explanation of Use of Non-GAAP Financial Measures
In addition to the results of operations presented in accordance with generally accepted accounting principles, or GAAP, in the United States, management uses, and this quarterly report references, net interest income and net interest margin, each on a fully taxable equivalent, or FTE, basis, which are non-GAAP financial measures. Management believes net interest income and net interest margin on an FTE basis provide information useful to investors in understanding our underlying business, operational performance and performance trends as they facilitate comparisons with the performance of other companies in the financial services industry. Although management believes that these non-GAAP financial measures enhance investors’ understanding of our business and performance, these non-GAAP financial measures should not be considered alternatives to GAAP or considered to be more important than financial results determined in accordance with GAAP, nor are they necessarily comparable with non-GAAP measures which may be presented by other companies.
We believe the presentation of net interest income and net interest margin on an FTE basis ensures the comparability of net interest income arising from both taxable and tax-exempt sources and is consistent with industry practice. Interest income (GAAP) per the Condensed Consolidated Statements of Comprehensive Income (Loss) is reconciled to net interest income adjusted on an FTE basis and net interest margin adjusted on an FTE basis in the "Results of Operations - Three and Nine Months Ended September 30, 2021 Compared to Three and Nine Months Ended September 30, 2020 - Net Interest Income" section of this MD&A.
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S&T BANCORP, INC. AND SUBSIDIARIES
Item 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS
RESULTS OF OPERATIONS
Three and Nine Months Ended September 30, 2021 Compared to
Three and Nine Months Ended September 30, 2020
Net Interest Income
Our principal source of revenue is net interest income. Net interest income represents the difference between the interest and fees earned on interest-earning assets and the interest paid on interest-bearing liabilities. Net interest income is affected by changes in the average balance of interest-earning assets and interest-bearing liabilities and changes in interest rates and spreads. The level and mix of interest-earning assets and interest-bearing liabilities is managed by our Asset and Liability Committee, or ALCO, in order to mitigate interest rate and liquidity risks of the balance sheet. A variety of ALCO strategies were implemented, within prescribed ALCO risk parameters, to produce what we believe is an acceptable level of net interest income.
The interest income on interest-earning assets and the net interest margin are presented on an FTE basis. The FTE basis adjusts for the tax benefit of income on certain tax-exempt loans and securities using the federal statutory tax rate of 21 percent for each period and the dividend-received deduction for equity securities. We believe this to be the preferred industry measurement of net interest income that provides a relevant comparison between taxable and non-taxable sources of interest income.
The following table reconciles interest income per the Condensed Consolidated Statements of Comprehensive Income (Loss) to net interest income and rates on an FTE basis for the periods presented:

| Three Months Ended September 30, | Nine Months Ended September 30,
(dollars in thousands) | 2021 |  | 2020 | 2021 |  | 2020
Total interest income |  | $ | 71,769 |  |  |  | $ | 76,848 |  |  | $ | 218,127 |  |  |  | $ | 244,916 |
Total interest expense |  | 3,058 |  |  |  | 7,572 |  |  | 10,453 |  |  |  | 35,456 |
Net Interest Income per Condensed Consolidated Statements of Comprehensive Income (Loss) |  | 68,711 |  |  |  | 69,276 |  |  | 207,674 |  |  |  | 209,460 |
Adjustment to FTE basis |  | 557 |  |  |  | 780 |  |  | 1,806 |  |  |  | 2,477 |
Net Interest Income on an FTE Basis (Non-GAAP) |  | $ | 69,268 |  |  |  | $ | 70,056 |  |  | $ | 209,480 |  |  |  | $ | 211,937 |
Net interest margin |  | 3.11 | % |  |  | 3.25 | % |  | 3.22 | % |  |  | 3.33 | %
Adjustment to FTE basis |  | 0.03 | % |  |  | 0.04 | % |  | 0.03 | % |  |  | 0.04 | %
Net Interest Margin on an FTE Basis (Non-GAAP) |  | 3.14 | % |  |  | 3.29 | % |  | 3.25 | % |  |  | 3.37 | %

Income amounts are annualized for rate calculations.
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S&T BANCORP, INC. AND SUBSIDIARIES
Item 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS
Average Balance Sheet and Net Interest Income Analysis (FTE)
The following tables provide information regarding the average balances, interest and rates earned on interest-earning assets and the average balances, interest and rates paid on interest-bearing liabilities for the periods presented:

| Three Months Ended September 30, 2021 |  | Three Months Ended September 30, 2020
(dollars in thousands) | Average Balance | Interest | Rate |  | Average Balance | Interest | Rate
ASSETS |  |  |  |  |  |  |  |  |
Interest-bearing deposits with banks | $ | 914,370 |  |  | $ | 374 |  | 0.16 | % |  | $ | 213,051 |  |  | $ | 61 |  | 0.11 | %
Securities, at fair value(1)(2) | 836,019 |  |  | 4,577 |  | 2.19 | % |  | 759,094 |  |  | 4,570 |  | 2.41 | %
Loans held for sale | 3,656 |  |  | 31 |  | 3.35 | % |  | 4,432 |  |  | 34 |  | 3.09 | %
Commercial real estate | 3,239,867 |  |  | 30,091 |  | 3.68 | % |  | 3,322,656 |  |  | 33,569 |  | 4.02 | %
Commercial and industrial | 1,744,684 |  |  | 18,329 |  | 4.17 | % |  | 2,107,750 |  |  | 18,300 |  | 3.45 | %
Commercial construction | 490,940 |  |  | 3,964 |  | 3.20 | % |  | 469,214 |  |  | 4,047 |  | 3.43 | %
Total Commercial Loans | 5,475,491 |  |  | 52,384 |  | 3.80 | % |  | 5,899,620 |  |  | 55,916 |  | 3.77 | %
Residential mortgage | 875,684 |  |  | 8,792 |  | 4.00 | % |  | 954,861 |  |  | 10,365 |  | 4.33 | %
Home equity | 547,984 |  |  | 4,612 |  | 3.34 | % |  | 536,735 |  |  | 5,037 |  | 3.73 | %
Installment and other consumer | 92,615 |  |  | 1,366 |  | 5.85 | % |  | 79,649 |  |  | 1,295 |  | 6.47 | %
Consumer construction | 13,626 |  |  | 126 |  | 3.66 | % |  | 14,475 |  |  | 157 |  | 4.32 | %
Total Consumer Loans | 1,529,909 |  |  | 14,896 |  | 3.87 | % |  | 1,585,720 |  |  | 16,854 |  | 4.24 | %
Total Portfolio Loans | 7,005,400 |  |  | 67,279 |  | 3.81 | % |  | 7,485,340 |  |  | 72,770 |  | 3.87 | %
Total Loans(1)(3) | 7,009,056 |  |  | 67,310 |  | 3.81 | % |  | 7,489,772 |  |  | 72,804 |  | 3.87 | %
Federal Home Loan Bank and other restricted stock | 9,981 |  |  | 65 |  | 2.62 | % |  | 15,157 |  |  | 193 |  | 5.11 | %
Total Interest-earning Assets | 8,769,425 |  |  | 72,326 |  | 3.28 | % |  | 8,477,074 |  |  | 77,628 |  | 3.65 | %
Noninterest-earning assets | 724,759 |  |  |  |  |  | 815,930 |  |  |  |
Total Assets | $ | 9,494,184 |  |  |  |  |  | $ | 9,293,004 |  |  |  |
LIABILITIES AND SHAREHOLDERS’ EQUITY |  |  |  |  |  |  |  |  |
Interest-bearing demand | $ | 962,139 |  |  | $ | 184 |  | 0.08 | % |  | $ | 967,735 |  |  | $ | 434 |  | 0.18 | %
Money market | 2,062,958 |  |  | 911 |  | 0.18 | % |  | 2,074,862 |  |  | 1,713 |  | 0.33 | %
Savings | 1,059,904 |  |  | 70 |  | 0.03 | % |  | 923,208 |  |  | 162 |  | 0.07 | %
Certificates of deposit | 1,240,345 |  |  | 1,274 |  | 0.41 | % |  | 1,486,016 |  |  | 4,317 |  | 1.16 | %
Total Interest-bearing Deposits | 5,325,346 |  |  | 2,439 |  | 0.18 | % |  | 5,451,821 |  |  | 6,626 |  | 0.48 | %
Securities sold under repurchase agreements | 71,054 |  |  | 18 |  | 0.10 | % |  | 64,000 |  |  | 41 |  | 0.25 | %
Short-term borrowings | — |  |  | — |  | — | % |  | 84,310 |  |  | 81 |  | 0.38 | %
Long-term borrowings | 22,841 |  |  | 114 |  | 1.99 | % |  | 49,269 |  |  | 311 |  | 2.52 | %
Junior subordinated debt securities | 64,118 |  |  | 487 |  | 3.01 | % |  | 64,057 |  |  | 513 |  | 3.19 | %
Total Borrowings | 158,012 |  |  | 619 |  | 1.56 | % |  | 261,636 |  |  | 946 |  | 1.44 | %
Total Interest-bearing Liabilities | 5,483,358 |  |  | 3,058 |  | 0.22 | % |  | 5,713,457 |  |  | 7,572 |  | 0.53 | %
Noninterest-bearing liabilities | 2,812,185 |  |  |  |  |  | 2,433,665 |  |  |  |
Shareholders' equity | 1,198,641 |  |  |  |  |  | 1,145,882 |  |  |  |
Total Liabilities and Shareholders' Equity | $ | 9,494,184 |  |  |  |  |  | $ | 9,293,004 |  |  |  |
Net Interest Income (1)(2) |  |  | $ | 69,268 |  |  |  |  |  | $ | 70,056 |  |
Net Interest Margin (1)(2) |  |  |  | 3.14 | % |  |  |  |  | 3.29 | %

(1) Tax-exempt interest income is on an FTE basis (non-GAAP) using the statutory federal corporate income tax rate of 21 percent for 2021 and 2020.
(2) Taxable investment income is adjusted for the dividend-received deduction for equity securities.
(3) Nonaccruing loans are included in the daily average loan amounts outstanding.
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| Nine months ended September 30, 2021 |  | Nine months ended September 30, 2020
(dollars in thousands) | Average Balance | Interest | Rate |  | Average Balance | Interest | Rate
ASSETS |  |  |  |  |  |  |  |  |
Interest-bearing deposits with banks | $ | 669,593 |  |  | $ | 613 |  | 0.12 | % |  | $ | 158,771 |  |  | $ | 449 |  | 0.38 | %
Securities, at fair value(1)(2) | 815,197 |  |  | 13,672 |  | 2.24 | % |  | 776,995 |  |  | 14,590 |  | 2.50 | %
Loans held for sale | 4,780 |  |  | 108 |  | 3.02 | % |  | 5,407 |  |  | 129 |  | 3.17 | %
Commercial real estate | 3,248,417 |  |  | 90,158 |  | 3.71 | % |  | 3,373,466 |  |  | 109,278 |  | 4.33 | %
Commercial and industrial | 1,863,447 |  |  | 57,509 |  | 4.13 | % |  | 2,020,179 |  |  | 57,771 |  | 3.82 | %
Commercial construction | 479,733 |  |  | 11,851 |  | 3.30 | % |  | 428,977 |  |  | 12,562 |  | 3.91 | %
Total Commercial Loans | 5,591,597 |  |  | 159,518 |  | 3.81 | % |  | 5,822,622 |  |  | 179,611 |  | 4.12 | %
Residential mortgage | 878,709 |  |  | 27,204 |  | 4.13 | % |  | 974,144 |  |  | 30,934 |  | 4.24 | %
Home equity | 538,931 |  |  | 14,085 |  | 3.49 | % |  | 540,220 |  |  | 16,530 |  | 4.09 | %
Installment and other consumer | 85,640 |  |  | 3,884 |  | 6.06 | % |  | 79,757 |  |  | 3,942 |  | 6.60 | %
Consumer construction | 14,257 |  |  | 525 |  | 4.92 | % |  | 12,587 |  |  | 423 |  | 4.49 | %
Total Consumer Loans | 1,517,538 |  |  | 45,698 |  | 4.02 | % |  | 1,606,708 |  |  | 51,829 |  | 4.31 | %
Total Portfolio Loans | 7,109,135 |  |  | 205,216 |  | 3.86 | % |  | 7,429,330 |  |  | 231,440 |  | 4.16 | %
Total Loans(1)(3) | 7,113,915 |  |  | 205,324 |  | 3.86 | % |  | 7,434,737 |  |  | 231,569 |  | 4.16 | %
Federal Home Loan Bank and other restricted stock | 10,579 |  |  | 323 |  | 4.07 | % |  | 19,473 |  |  | 785 |  | 5.38 | %
Total Interest-earning Assets | 8,609,284 |  |  | 219,933 |  | 3.41 | % |  | 8,389,976 |  |  | 247,393 |  | 3.94 | %
Noninterest-earning assets | 728,314 |  |  |  |  |  | 772,404 |  |  |  |
Total Assets | $ | 9,337,598 |  |  |  |  |  | $ | 9,162,380 |  |  |  |
LIABILITIES AND SHAREHOLDERS’ EQUITY |  |  |  |  |  |  |  |  |
Interest-bearing demand | $ | 952,297 |  |  | $ | 636 |  | 0.09 | % |  | $ | 981,174 |  |  | $ | 2,425 |  | 0.33 | %
Money market | 2,023,583 |  |  | 2,748 |  | 0.18 | % |  | 2,048,466 |  |  | 10,610 |  | 0.69 | %
Savings | 1,033,581 |  |  | 291 |  | 0.04 | % |  | 880,673 |  |  | 801 |  | 0.12 | %
Certificates of deposit | 1,291,666 |  |  | 4,896 |  | 0.51 | % |  | 1,549,177 |  |  | 17,355 |  | 1.50 | %
Total Interest-bearing Deposits | 5,301,126 |  |  | 8,572 |  | 0.22 | % |  | 5,459,490 |  |  | 31,191 |  | 0.76 | %
Securities sold under repurchase agreements | 67,872 |  |  | 60 |  | 0.12 | % |  | 60,045 |  |  | 137 |  | 0.30 | %
Short-term borrowings | 8,425 |  |  | 12 |  | 0.19 | % |  | 182,623 |  |  | 1,392 |  | 1.02 | %
Long-term borrowings | 23,139 |  |  | 346 |  | 2.00 | % |  | 50,292 |  |  | 950 |  | 2.52 | %
Junior subordinated debt securities | 64,103 |  |  | 1,463 |  | 3.05 | % |  | 64,099 |  |  | 1,786 |  | 3.72 | %
Total Borrowings | 163,539 |  |  | 1,882 |  | 1.54 | % |  | 357,059 |  |  | 4,265 |  | 1.60 | %
Total Interest-bearing Liabilities | 5,464,665 |  |  | 10,453 |  | 0.26 | % |  | 5,816,549 |  |  | 35,456 |  | 0.81 | %
Noninterest-bearing liabilities | 2,693,530 |  |  |  |  |  | 2,170,447 |  |  |  |
Shareholders' equity | 1,179,403 |  |  |  |  |  | 1,175,384 |  |  |  |
Total Liabilities and Shareholders' Equity | $ | 9,337,598 |  |  |  |  |  | $ | 9,162,380 |  |  |  |
Net Interest Income (1) (2) |  |  | $ | 209,480 |  |  |  |  |  | $ | 211,937 |  |
Net Interest Margin |  |  |  | 3.25 | % |  |  |  |  | 3.37 | %

(1) Tax-exempt interest income is on an FTE basis (non-GAAP) using the statutory federal corporate income tax rate of 21 percent for 2021 and 2020.
(2) Taxable investment income is adjusted for the dividend-received deduction for equity securities.
(3) Nonaccruing loans are included in the daily average loan amounts outstanding.
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Net interest income on an FTE basis (non-GAAP) decreased $0.8 million and $2.5 million for the three and nine months ended September 30, 2021 compared to the same periods in 2020. The decline was primarily due to lower average loan balances compared to the prior periods. Net interest income was favorably impacted by PPP loans which contributed $4.2 million and $14.2 million for the three and nine months ended September 30, 2021 compared to $3.2 million and $6.4 million for the same periods in 2020. The net interest margin, or NIM, on an FTE basis (non-GAAP) decreased 15 and 12 basis points for the three and nine months ended September 30, 2021 compared to the same periods in 2020. The decrease in NIM on an FTE basis is primarily due to higher average cash balances in the current periods and the low interest rate environment. PPP loans positively impacted the net interest margin on an FTE basis (non-GAAP) by 10 and 8 basis points for the three and nine months ended September 30, 2021 compared to the negative impact of 7 and 4 basis points in the prior periods.
Interest income on an FTE basis (non-GAAP) decreased $5.3 million and $27.5 million for the three and nine months ended September 30, 2021 compared to the same periods in 2020. The decrease in interest income was primarily due to lower average loan balances and the low rate interest environment compared to the same periods in 2020. Average loan balances decreased $480.7 million and $320.8 million for the three and nine months ended September 30, 2021 compared to the same periods in 2020. Average PPP loans decreased $284.3 million and increased $58.1 million for the three and nine months ended September 30, 2021 compared to the same periods in 2020. The average rate earned on loans decreased 6 and 30 basis points for the three and nine months ended September 30, 2021 compared to the same periods in 2020 primarily due to lower short-term interest rates. Average interest-bearing deposits with banks increased $701.3 million and $510.8 million for the three and nine months ended September 30, 2021 compared to the same periods in 2020 due to PPP forgiveness, lower loan balances and a significant increase in average deposits as a result of customer PPP loans and stimulus payments along with customers' liquidity preferences. Overall, the FTE rate on interest-earning assets (non-GAAP) decreased 37 and 53 basis points for the three and nine months ended September 30, 2021 compared to the same periods in 2020.
Interest expense decreased $4.5 million and $25.0 million for the three and nine months ended September 30, 2021 compared to the same periods in 2020. The decreases were primarily due to lower short-term interest rates compared to the same periods in 2020. Average interest-bearing deposits decreased $126.5 million and $158.4 million for the three and nine months ended September 30, 2021 compared to the same periods in 2020. The average rate paid on interest-bearing deposits decreased 30 and 54 basis points compared to the same periods in 2020 primarily due to lower short-term interest rates. The interest-bearing deposit decreases are favorably offset by $425.2 million and $538.4 million increases in demand deposits for the three and nine months ended September 30, 2021. We experienced demand deposit growth due to customer PPP loans and stimulus payments along with customers' liquidity preferences. Brokered deposits decreased $163.1 million and $267.2 million for the three and nine months ended September 30, 2021 compared to the same periods in 2020 due to this funding source no longer being needed. Average total borrowings decreased $103.6 million and $193.5 million for the three and nine months ended September 30, 2021 compared to the same periods in 2020 due to this funding source no longer being needed. Overall, the cost of interest-bearing liabilities decreased 31 and 55 basis points for the three and nine months ended September 30, 2021 compared to the same periods in 2020.
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The following table sets forth for the periods presented a summary of the changes in interest earned and interest paid resulting from changes in volume and changes in rates:

| Three Months Ended September 30, 2021 Compared to September 30, 2020 |  | Nine Months Ended September 30, 2021 Compared to September 30, 2020
(dollars in thousands) | Volume (4) | Rate (4) | Total |  | Volume (4) | Rate (4) | Total
Interest earned on: |  |  |  |  |  |  |
Interest-bearing deposits with banks | $ | 200 |  | $ | 113 |  | $ | 313 |  |  | $ | 1,444 |  | $ | (1,280) |  | $ | 164 |
Securities, at fair value(1)(2) | 463 |  | (456) |  | 7 |  |  | 717 |  | (1,635) |  | (917) |
Loans held for sale | (6) |  | 2 |  | (4) |  |  | (15) |  | (5) |  | (21) |
Commercial real estate | (836) |  | (2,642) |  | (3,478) |  |  | (4,051) |  | (15,071) |  | (19,120) |
Commercial and industrial | (3,152) |  | 3,181 |  | 29 |  |  | (4,482) |  | 4,220 |  | (262) |
Commercial construction | 187 |  | (270) |  | (82) |  |  | 1,486 |  | (2,196) |  | (710) |
Total Commercial Loans | (3,801) |  | 270 |  | (3,532) |  |  | (7,047) |  | (13,047) |  | (20,093) |
Residential mortgage | (859) |  | (713) |  | (1,573) |  |  | (3,031) |  | (699) |  | (3,730) |
Home equity | 106 |  | (530) |  | (425) |  |  | (39) |  | (2,405) |  | (2,445) |
Installment and other consumer | 211 |  | (139) |  | 71 |  |  | 291 |  | (349) |  | (58) |
Consumer construction | (9) |  | (22) |  | (31) |  |  | 56 |  | 46 |  | 102 |
Total Consumer Loans | (552) |  | (1,405) |  | (1,958) |  |  | (2,723) |  | (3,408) |  | (6,131) |
Total Portfolio Loans | (4,354) |  | (1,136) |  | (5,491) |  |  | (9,770) |  | (16,455) |  | (26,224) |
Total Loans (1)(3) | (4,360) |  | (1,134) |  | (5,494) |  |  | (9,785) |  | (16,460) |  | (26,244) |
Federal Home Loan Bank and other restricted stock | (66) |  | (62) |  | (128) |  |  | (359) |  | (104) |  | (462) |
Change in Interest Earned on Interest-earning Assets | $ | (3,762) |  | $ | (1,539) |  | $ | (5,301) |  |  | $ | (7,981) |  | $ | (19,478) |  | $ | (27,460) |
Interest paid on: |  |  |  |  |  |  |
Interest-bearing demand | $ | (3) |  | $ | (247) |  | $ | (250) |  |  | $ | (71) |  | $ | (1,718) |  | $ | (1,789) |
Money market | (10) |  | (793) |  | (803) |  |  | (129) |  | (7,733) |  | (7,862) |
Savings | 24 |  | (117) |  | (93) |  |  | 139 |  | (649) |  | (510) |
Certificates of deposit | (714) |  | (2,329) |  | (3,043) |  |  | (2,885) |  | (9,574) |  | (12,459) |
Total Interest-bearing Deposits | (702) |  | (3,486) |  | (4,188) |  |  | (2,946) |  | (19,674) |  | (22,620) |
Securities sold under repurchase agreements | 4 |  | (27) |  | (23) |  |  | 18 |  | (95) |  | (77) |
Short-term borrowings | — |  | — |  | — |  |  | — |  | — |  | — |
Long-term borrowings | (167) |  | (30) |  | (197) |  |  | (513) |  | (91) |  | (604) |
Junior subordinated debt securities | — |  | (26) |  | (26) |  |  | — |  | (323) |  | (322) |
Total Borrowings | (162) |  | (84) |  | (246) |  |  | (495) |  | (508) |  | (1,003) |
Change in Interest Paid on Interest-bearing Liabilities | (864) |  | (3,569) |  | $ | (4,433) |  |  | (3,441) |  | (20,182) |  | (23,623) |
Change in Net Interest Income | $ | (2,898) |  | $ | 2,030 |  | $ | (868) |  |  | $ | (4,540) |  | $ | 703 |  | $ | (3,837) |

(1) Tax-exempt income is on an FTE basis (non-GAAP) using the statutory federal corporate income tax rate of 21 percent for 2021 and 2020.
(2) Taxable investment income is adjusted for the dividend-received deduction for equity securities.
(3) Nonaccruing loans are included in the daily average loan amounts outstanding.
(4) Changes to rate/volume are allocated to both rate and volume on a proportionate dollar basis.
Provision for Credit Losses
The provision for credit losses, which includes a provision for losses on loans and on unfunded commitments, is a charge to earnings to maintain the ACL at a level consistent with management's assessment of expected losses in the loan portfolio at the balance sheet date. The provision for credit losses decreased $14.1 million and $115.2 million to $3.4 million and $9.1 million for the three and nine months ended September 30, 2021 compared to $17.5 million and $124.3 million for the same periods in 2020. The provision for credit losses included $1.1 million and $1.5 million for the reserve for unfunded commitments for the three and nine months ended September 30, 2021 compared to $(1.8) million and $0.7 million for the same periods in 2020. The increase in the reserve for unfunded loan commitments for the three and nine months ended September 30, 2021 was due to an increase in overall unused commitments in the C&I portfolio and an increase in loss rates primarily in the construction portfolio
The significant decrease in the provision for credit losses during the nine months ended September 30, 2021 was mainly due to the customer fraud in 2020 discussed below. The decrease in the provision for credit losses during the three and nine months ended September 30, 2021 was due to an improved economic forecast in 2021 compared to 2020. Our economic
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forecast covers a period of two years and is driven primarily by national unemployment data. The forecasted national unemployment rate improved at September 30, 2021 compared to the same time in 2020.
For the three and nine months ended September 30, 2021, we had net charge-offs of $3.6 million and $16.9 million compared to $12.9 million and $92.1 million for the same periods in 2020. The most significant charge-offs for the nine months ended September 30, 2021 were to three CRE relationships totaling $10.1 million and a C&I relationship totaling $3.9 million.
During the three months ended June 30, 2020, we recognized a charge-off of $58.7 million related to a customer fraud from a check kiting scheme. We continue to pursue all available resources of recovery to mitigate the loss. The customer also had a lending relationship of $15.1 million that had $8.9 million of charge-offs during 2020 and $0.5 million during the three months ended March 31, 2021. We received recoveries of $0.9 million on the lending relationship for the nine months ended September 30, 2021.
Nonperforming loans increased $27.2 million to $111.3 million at September 30, 2021 compared to $84.1 million at September 30, 2020. The increase in nonperforming loans primarily related to the addition of $36.0 million of hotel loans which moved to nonperforming during the fourth quarter of 2020 as a result of continued deterioration due to the pandemic and the addition of a $21.7 million C&I relationship which moved to nonperforming during the three months ended September 30, 2021 due to financial deterioration that led to cash flow shortfalls. A specific reserve of $9.3 million was established based on an estimated enterprise value of the company. The increase in nonperforming loans was partially offset by two CRE hotel loans totaling $11.8 million that moved back to performing status and two CRE loans totaling $12.2 million that moved to OREO, all of which occurred during the three months ended September 30, 2021. An additional offset to the increase in nonperforming loans was a $4.9 million charge-off of a CRE relationship which occurred during the three months ended June 30, 2021.
Noninterest Income

| Three Months Ended September 30, | Nine Months Ended September 30,
(dollars in thousands) | 2021 | 2020 | $ Change | % Change | 2021 | 2020 | $ Change | % Change
Net gain on sale of securities |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | — |  |  | $ | 29 |  |  | $ | 142 |  |  | $ | (113) |  |  | (79.6) |
Debit and credit card |  | 4,579 |  |  | 4,171 |  |  | 408 |  |  | 9.8 | % |  | 13,486 |  |  | 11,264 |  |  | 2,222 |  |  | 19.7 | %
Mortgage banking |  | 2,162 |  |  | 3,964 |  |  | (1,802) |  |  | (45.5) | % |  | 8,206 |  |  | 7,823 |  |  | 383 |  |  | 4.9 | %
Service charges on deposit accounts |  | 3,923 |  |  | 3,303 |  |  | 620 |  |  | 18.8 | % |  | 11,039 |  |  | 10,124 |  |  | 915 |  |  | 9.0 | %
Wealth management |  | 3,464 |  |  | 2,522 |  |  | 942 |  |  | 37.4 | % |  | 9,576 |  |  | 7,471 |  |  | 2,105 |  |  | 28.2 | %
Commercial loan swap income |  | 184 |  |  | 499 |  |  | (315) |  |  | (63.1) | % |  | 577 |  |  | 3,928 |  |  | (3,351) |  |  | (85.3) | %
Other |  | 1,534 |  |  | 2,024 |  |  | (490) |  |  | (24.2) | % |  | 5,595 |  |  | 3,358 |  |  | 2,237 |  |  | 66.6 | %
Total Noninterest Income |  | $ | 15,846 |  |  | $ | 16,483 |  |  | $ | (637) |  |  | (3.9) | % |  | $ | 48,508 |  |  | $ | 44,110 |  |  | $ | 4,397 |  |  | 10.0 | %

Noninterest income decreased $0.6 million and increased $4.4 million for the three and nine months ended September 30, 2021 compared to the same periods in 2020. Debit and credit card income increased $0.4 million and $2.2 million for the three and nine months ended September 30, 2021 due to increased activity related to the improving economic environment and increased merchant revenue. Service charges on deposit accounts increased $0.6 million and $0.9 million due to fee changes and the improving economic environment. Wealth management income increased $0.9 million and $2.1 million due to higher assets under management from market appreciation and an increase in customer activity. Mortgage banking decreased $1.8 million for the three months ended and increased $0.4 million for the nine months ended September 30, 2021.The decrease for the three months ended primarily related to a lower volume of loans sold than in the prior year same period. The increase for the nine months ended was mainly due to changes in the valuation of the mortgage derivative and mortgage servicing rights compared to the same periods in 2020. Other income decreased $0.5 million for the three months ended September 30, 2021 and increased $2.2 million for the nine months ended September 30, 2021 due to changes in the valuation of our deferred compensation plan, which has a corresponding offset in salaries and employee benefits expense resulting in no impact to net income, and the change in value in the equity securities portfolio compared to the same periods in 2020. Commercial loan swap income decreased $0.3 million and $3.4 million for the three and nine months ended September 30, 2021 as activity was significant in the first half of 2020, but activity has declined due to the pandemic and the interest rate environment.
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Noninterest Expense

| Three Months Ended September 30, | Nine Months Ended September 30,
(dollars in thousands) | 2021 | 2020 | $ Change | % Change |  | 2021 | 2020 | $ Change | % Change
Salaries and employee benefits(1) |  | $ | 25,228 |  |  | $ | 24,571 |  |  | $ | 657 |  |  | 2.7 | % |  | $ | 73,070 |  |  | $ | 67,326 |  |  | $ | 5,744 |  |  | 8.5 | %
Data processing and information technology(1) |  | 4,001 |  |  | 4,218 |  |  | (217) |  |  | (5.1) | % |  | 12,012 |  |  | 11,671 |  |  | 341 |  |  | 2.9 | %
Occupancy(1) |  | 3,660 |  |  | 3,441 |  |  | 219 |  |  | 6.4 | % |  | 10,921 |  |  | 10,643 |  |  | 278 |  |  | 2.6 | %
Furniture, equipment and software(1) |  | 2,745 |  |  | 2,440 |  |  | 305 |  |  | 12.5 | % |  | 7,787 |  |  | 7,965 |  |  | (178) |  |  | (2.2) | %
Professional services and legal(1) |  | 1,550 |  |  | 1,911 |  |  | (361) |  |  | (18.9) | % |  | 4,718 |  |  | 4,890 |  |  | (172) |  |  | (3.5) | %
FDIC insurance |  | 1,210 |  |  | 1,900 |  |  | (690) |  |  | (36.3) | % |  | 3,180 |  |  | 3,718 |  |  | (538) |  |  | (14.5) | %
Marketing(1) |  | 890 |  |  | 1,793 |  |  | (903) |  |  | (50.4) | % |  | 3,208 |  |  | 3,883 |  |  | (675) |  |  | (17.4) | %
Other taxes |  | 1,830 |  |  | 1,612 |  |  | 218 |  |  | 13.5 | % |  | 5,098 |  |  | 4,816 |  |  | 282 |  |  | 5.9 | %
Merger related expenses |  | — |  |  | — |  |  | — |  |  | — | % |  | — |  |  | 2,342 |  |  | (2,342) |  |  | (100.0) | %
Other(1) |  | 6,127 |  |  | 6,360 |  |  | (233) |  |  | (3.7) | % |  | 18,656 |  |  | 20,861 |  |  | (2,205) |  |  | (10.6) | %
Total Noninterest Expense |  | $ | 47,241 |  |  | $ | 48,246 |  |  | $ | (1,005) |  |  | (2.1) | % |  | $ | 138,650 |  |  | $ | 138,115 |  |  | $ | 535 |  |  | 0.4 | %

(1) Excludes merger related expenses for 2020 amounts only
Noninterest expense decreased $1.0 million to $47.2 million for the three months ended September 30, 2021 and increased $0.5 million to $138.6 million for the nine months ended September 30, 2021 compared to the same periods in 2020. Salaries and employee benefits increased $0.7 million and $5.7 million for the three and nine months ended September 30, 2021 due to higher deferred origination costs related to PPP loans in 2020, higher payroll incentives and restricted stock expense, a change in the valuation related to a deferred compensation plan, which has a corresponding offset in other noninterest income resulting in no impact to net income, and higher pension expense due to an increase in retirees electing lump-sum distributions causing settlement accounting and higher medical expenses. Professional services and legal expenses decreased $0.4 million for the three months ended September 30, 2021 and decreased $0.2 million for the nine months ended September 30, 2021 mainly due to lower legal expense for both periods. FDIC insurance decreased $0.7 million and $0.5 million for the three and nine months ended September 30, 2021 due to improvements in the financial ratios used to determine the assessment. Marketing expense decreased $0.9 million and $0.7 million for the three and nine months ended due to the timing of various initiatives. Other noninterest expense decreased during the nine months ended September 30, 2021 due to lower amortization related to our qualified affordable housing projects and core deposit intangible asset compared to the same period in 2020. Total merger related expenses of $2.3 million for the nine months ended September 30, 2020 included $1.4 million of salaries and employee benefits, $0.4 million for data processing, $0.2 million for professional services and $0.3 million in various other expenses.
Provision for Income Taxes
The provision for income taxes increased $3.0 million and $26.3 million to $6.3 million and $20.6 million for the three and nine months ended September 30, 2021 compared to the same periods in 2020. The increase in income tax expense was primarily due to the increase in pretax income for both periods compared to the same periods in 2020. The increase in pretax income in the nine months ended September 30, 2021 was primarily due to the loss incurred from the customer fraud in the same period in 2020 and for the three months ended September 30, 2021, was primarily due to the reduced provision for credit losses as a result of the improved economic forecast. Our effective tax rate was 18.7 percent and 19.0 percent for the three and nine months ended September 30, 2021 compared to 16.6 percent and (64.5) percent for the same period in 2020. The change in our effective tax rate for the three and nine months ended September 30, 2021 was primarily due to the increases in pretax income compared to 2020.
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Item 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS
Financial Condition as of September 30, 2021
Total assets increased $468.2 million to $9.4 billion at September 30, 2021 compared to $9.0 billion at December 31, 2020. Cash and due from banks increased $704.7 million to $934.4 million at September 30, 2021 compared to December 31, 2020 due to PPP forgiveness and a significant increase in deposits as a result of government stimulus programs, a second round of PPP loans and our customers' liquidity preferences. Total portfolio loans decreased $255.8 million to $7.0 billion at September 30, 2021 compared to $7.2 billion at December 31, 2020. The commercial loan portfolio decreased $249.7 million compared to December 31, 2020. C&I loans decreased $255.7 million which mainly related to a net decline in PPP loans of $284.4 million since December 31, 2020. The consumer loan portfolio decreased $6.0 million with decreases in residential mortgage of $30.5 million and consumer construction of $5.5 million offset by increases in home equity of $13.2 million and other consumer of $16.7 million. Excluding the PPP loans, portfolio loans increased $28.7 million compared to December 31, 2020.
Securities increased $96.4 million to $870.1 million at September 30, 2021 from $773.7 million at December 31, 2020. The increase in securities is primarily due to an increase in overall investing activities. The bond portfolio had a net unrealized gain of $18.3 million at September 30, 2021 compared to $33.4 million at December 31, 2020 due to rising long-term interest rates during the first nine months of 2021.
Our deposits increased $524.6 million, with total deposits of $7.9 billion at September 30, 2021 compared to $7.4 billion at December 31, 2020. Customer deposits increased $587.8 million from December 31, 2020. The increase in customer deposits primarily related to government stimulus programs, PPP loans and our customers' liquidity preferences. Total brokered deposits decreased $63.2 million from December 31, 2020 due to a reduced need for wholesale funding due to strong customer deposit growth.
Total borrowings decreased $68.5 million to $159.4 million at September 30, 2021 compared to $227.9 million at December 31, 2020 due to increased customer deposits. The decrease in borrowings is primarily related to a decline in short-term borrowings of $75.0 million compared to December 31, 2020.
Total shareholders’ equity increased by $47.0 million to $1.2 billion at both September 30, 2021 and December 31, 2020. The increase was primarily due to net income of $87.9 million offset partially by dividends of $33.0 million and a decrease in other comprehensive income of $10.0 million. The $10.0 million decrease in other comprehensive income was due to a $11.9 million decrease in unrealized gains on our available-for-sale investment securities and a $1.9 million change in the funded status of our employee benefit plans, net of taxes.
Securities Activity

(dollars in thousands) | September 30, 2021 |  | December 31, 2020 |  | $ Change
U.S. Treasury securities |  | $ | 85,300 |  |  |  | $ | 10,282 |  |  |  | $ | 75,018 |
Obligations of U.S. government corporations and agencies |  | 71,205 |  |  |  | 82,904 |  |  |  | (11,699) |
Collateralized mortgage obligations of U.S. government corporations and agencies |  | 208,985 |  |  |  | 209,296 |  |  |  | (311) |
Residential mortgage-backed securities of U.S. government corporations and agencies |  | 60,442 |  |  |  | 67,778 |  |  |  | (7,336) |
Commercial mortgage-backed securities of U.S. government corporations and agencies |  | 356,506 |  |  |  | 273,681 |  |  |  | 82,825 |
Corporate obligations |  | 500 |  |  |  | 2,025 |  |  |  | (1,525) |
Obligations of states and political subdivisions |  | 86,056 |  |  |  | 124,427 |  |  |  | (38,371) |
Available-for-Sale Debt Securities |  | 868,994 |  |  |  | 770,393 |  |  |  | 98,601 |
Marketable equity securities |  | 1,127 |  |  |  | 3,300 |  |  |  | (2,173) |
Total Securities |  | $ | 870,121 |  |  |  | $ | 773,693 |  |  |  | $ | 96,428 |

We invest in various securities in order to maintain a source of liquidity, to satisfy various pledging requirements, to increase net interest income and as a tool of ALCO to reposition the balance sheet for interest rate risk purposes. Securities are subject to market risks that could negatively affect the level of liquidity available to us. Security purchases are subject to an investment policy approved annually by our Board of Directors and administered through ALCO and our treasury function. Securities increased $96.4 million to $870.1 million at September 30, 2021 from $773.7 million at December 31, 2020. The increase in securities is primarily due to an increase in overall investing activities due to excess liquidity.
At September 30, 2021 our bond portfolio was in a net unrealized gain position of $18.3 million compared to a net unrealized gain position of $33.4 million at December 31, 2020. At September 30, 2021 total gross unrealized gains in the bond portfolio were $21.4 million offset by gross unrealized losses of $3.1 million compared to December 31, 2020, when total gross unrealized gains were $33.5 million offset by gross unrealized losses of $0.1 million. The decrease in the net unrealized gain position was primarily due to an increase in interest rates from December 31, 2020 to September 30, 2021.
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Item 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS
Loan Composition

| September 30, 2021 |  |  | December 31, 2020
(dollars in thousands) | Amount | % of Loans |  |  | Amount | % of Loans
Commercial |  |  |  |  |  |
Commercial real estate | $ | 3,225,863 |  | 46.3 | % |  |  | $ | 3,244,974 |  | 44.9 | %
Commercial and industrial | 1,698,784 |  | 24.4 | % |  |  | 1,954,453 |  | 27.0 | %
Commercial construction | 499,317 |  | 7.2 | % |  |  | 474,280 |  | 6.6 | %
Total Commercial Loans | 5,423,964 |  | 77.8 | % |  |  | 5,673,707 |  | 78.5 | %
Consumer |  |  |  |  |  |
Consumer real estate | 1,448,517 |  | 20.8 | % |  |  | 1,471,238 |  | 20.4 | %
Other consumer | 97,606 |  | 1.4 | % |  |  | 80,915 |  | 1.1 | %
Total Consumer Loans | 1,546,123 |  | 22.2 | % |  |  | 1,552,153 |  | 21.5 | %
Total Portfolio Loans | 6,970,087 |  | 100.0 | % |  |  | 7,225,860 |  | 100.0 | %
Loans held for sale | 4,303 |  |  |  |  | 18,528 |  |
Total Loans | $ | 6,974,389 |  |  |  |  | $ | 7,244,388 |  |

The loan portfolio represents the most significant source of interest income for us. The risk that borrowers will be unable to pay such obligations is inherent in the loan portfolio. Other conditions such as downturns in the borrower’s industry or the overall economic climate can significantly impact the borrower’s ability to pay. As of September 30, 2021, 73 percent of our total loans are variable rate loans and 27 percent are fixed rate loans. Total portfolio loans decreased $255.8 million to $7.0 billion at September 30, 2021 compared to December 31, 2020. P ortfolio loans excluding PPP loans increased $28.7 million compared to December 31, 2020.
Commercial loans, including CRE, C&I and commercial construction, comprised 77.8 percent of total portfolio loans at September 30, 2021 and 78.5 percent at December 31, 2020. The commercial loan portfolio decreased $249.7 million at September 30, 2021 compared to December 31, 2020. C&I loans decreased $255.7 million at September 30, 2021 which mainly related to a net PPP decline of $284.5 million since December 31, 2020.
As of September 30, 2021, we had $181.0 million of PPP loans included in C&I compared to $465.5 million at December 31, 2020. PPP loans are forgivable, in whole or in part, if the proceeds are used for payroll and other permitted expenses in accordance with the requirements of the PPP. These loans carry a fixed rate of 1 percent and a term of two years, or five years for loans approved by the SBA on or after June 5, 2020. Payments are deferred for the first six months of the loan. The loans are 100 percent guaranteed by the SBA. The SBA pays us a processing fee ranging from 1 percent to 5 percent based on the size of the loan.
Consumer loans represent 22.2 percent of our total portfolio loans at September 30, 2021 and 21.5 percent in December 31, 2020. The consumer loan portfolio decreased $6.0 million at September 30, 2021 with decreases in residential mortgage of $30.4 million and consumer construction of $5.5 million offset by increases in home equity of $13.2 million and other consumer of $16.7 million.
Allowance for Credit Losses
We maintain an ACL at a level determined to be adequate to absorb estimated expected credit losses within the loan portfolio over the contractual life of an instrument that considers our historical loss experience, current conditions and forecasts of future economic conditions as of the balance sheet date. We develop and document a systematic ACL methodology based on the following portfolio segments: 1) Commercial Real Estate, or CRE, 2) Commercial and Industrial, or C&I, 3) Commercial Construction, 4) Business Banking, 5) Consumer Real Estate and 6) Other Consumer. Refer to Part 1. Financial Information, Note 6. Allowance for Credit Losses for details on our portfolio segments.
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Item 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS
The following table presents activity in the ACL for the periods presented:

| Nine Months Ended September 30, 2021
(dollars in thousands) | Commercial Real Estate |  | Commercial and Industrial |  | Commercial Construction |  | Business Banking |  | Consumer Real Estate |  | Other Consumer |  | Total Loans
Allowance for credit losses on loans: |  |  |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of period | $ | 65,656 |  |  | $ | 16,100 |  |  | $ | 7,239 |  |  | $ | 15,917 |  |  | $ | 10,014 |  |  | $ | 2,686 |  |  | $ | 117,612 |
Provision for credit losses on loans(1) | (2,922) |  |  | 14,552 |  |  | 54 |  |  | (2,736) |  |  | (1,335) |  |  | (1) |  |  | 7,612 |
Charge-offs | (12,030) |  |  | (4,777) |  |  | (56) |  |  | (1,494) |  |  | (422) |  |  | (698) |  |  | (19,477) |
Recoveries | 966 |  |  | 364 |  |  | 5 |  |  | 454 |  |  | 267 |  |  | 545 |  |  | 2,601 |
Net (Charge-offs)/Recoveries | (11,064) |  |  | (4,413) |  |  | (51) |  |  | (1,040) |  |  | (155) |  |  | (153) |  |  | (16,876) |
Balance at End of Period | $ | 51,670 |  |  | $ | 26,239 |  |  | $ | 7,242 |  |  | $ | 12,141 |  |  | $ | 8,524 |  |  | $ | 2,532 |  |  | $ | 108,348 |
(1) Excludes the provision for credit losses for unfunded commitments.

| September 30, 2021 |  | December 31, 2020 |
Ratio of net charge-offs to average loans outstanding(1) | 0.32 | % |  | 0.61 | % | (2)
Allowance for credit losses as a percentage of total portfolio loans | 1.55 | % |  | 1.63 | % |
Allowance for loan losses as a percentage of total portfolio loans - excluding PPP loans | 1.60 | % |  | 1.74 | % |
Allowance for credit losses to nonperforming loans | 97 | % |  | 80 | % |

(1) Annualized
(2) Excludes $58.7 million loan charge-off related to a customer fraud in the three months ended June 30, 2020.
The ACL decreased $9.3 million to $108.3 million at September 30, 2021 compared to $117.6 million at December 31, 2020. Our total qualitative reserve decreased $8.7 million for the period ended September 30, 2021 compared to December 31, 2020 due to improved economic trends and forecast. Specific reserves on loans individually assessed decreased $3.6 million to $9.9 million at September 30, 2021 compared to $13.5 million at December 31, 2020. The decrease in specific reserves was a result of approximately $7.5 million of loan charge-offs. Additionally, $4.1 million of specific reserves were released related to three CRE hotel loans due to fair value improvements during the three months ended September 30, 2021. Offsetting this decrease in specific reserves was the addition of a $21.7 million C&I loan which required a $9.3 million specific reserve at September 30, 2021.
Net loan charge-offs were $3.6 million, or 0.21 percent of average loans and $16.9 million, or 0.32 percent of average loans for the three and nine months ended September 30, 2021. The most significant charge-offs for the nine months ending September 30, 2021 were three CRE relationships for a total of $10.1 million and a C&I relationship for $3.9 million. The charge-offs were the result of fair value declines.
Substandard loans decreased $3.9 million to $283.2 million at September 30, 2021 compared to $287.1 million at December 31, 2020. The decrease in substandard loans was primarily due to charge-offs of $10.7 million, payoffs of three CRE relationships for a total of $14.4 million and two CRE loans for a total of $12.2 million that moved to OREO. The decrease in substandard loans was offset by the addition of two CRE relationships totaling $16.8 million and a C&I relationship totaling $21.7 million which were all downgraded to substandard due to financial deterioration that led to cash flow shortfalls. Special mention loans improved significantly from December 31, 2020 with a decrease of $58.2 million, or 21.6 percent, to $211.7 million at September 30, 2021 compared to $269.9 million at December 31, 2020. The decrease in special mention loans was primarily due to various payoffs and upgrades to pass ratings.
Troubled debt restructurings, or TDRs, decreased $18.9 million to $27.8 million at September 30, 2021 compared to $46.7 million at December 31, 2020. The decrease in TDRs was primarily due to payoffs of $4.8 million and $3.7 million on two CRE relationships and a $6.1 million CRE loan moved to OREO at September 30, 2021. Total TDRs of $27.8 million included $13.8 million, or 49.6 percent, that were performing and $14.0 million, or 50.4 percent, that were nonperforming at September 30, 2021.
Our allowance for credit losses on unfunded commercial lending commitments and letters of credit provide for the risk of expected loss in these arrangements. The allowance is computed using a methodology similar to that used to determine the ACL for loans, modified to take into account the probability of a draw-down on the commitment. The provision for credit losses on unfunded loan commitments is included in the provision for credit losses on our Condensed Consolidated Statements of Comprehensive Income (Loss). The allowance for unfunded loan commitments increased $1.4 million to $5.9 million at September 30, 2021 compared to $4.5 million at December 31, 2020. This change was due to an increase in the overall unused commitments in the C&I portfolio and higher loss rates, primarily in the construction portfolio. The allowance for unfunded commitments is included in other liabilities in the Consolidated Balance Sheets.
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Item 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS
Nonperforming assets consist of nonaccrual loans, nonaccrual TDRs and OREO. The following table summarizes nonperforming assets for the dates presented:

(dollars in thousands) | September 30, 2021 |  | December 31, 2020 |  | $ Change
Nonperforming Loans |  |  |  |  |  |  |  |
Commercial real estate |  | $ | 43,704 |  |  |  | $ | 84,416 |  |  |  | $ | (40,712) |
Commercial and industrial |  | 33,909 |  |  |  | 7,100 |  |  |  | 26,809 |
Commercial construction |  | 4,053 |  |  |  | 384 |  |  |  | 3,669 |
Business banking |  | 8,729 |  |  |  | 16,692 |  |  |  | (7,963) |
Consumer real estate |  | 6,695 |  |  |  | 8,798 |  |  |  | (2,103) |
Other Consumer |  | 189 |  |  |  | 96 |  |  |  | 93 |
Total Nonperforming Loans |  | 97,279 |  |  |  | 117,486 |  |  |  | (20,207) |
Nonperforming Troubled Debt Restructurings |  |  |  |  |  |  |  |
Commercial real estate |  | 11,093 |  |  |  | 16,654 |  |  |  | (5,561) |
Commercial and industrial |  | — |  |  |  | 9,885 |  |  |  | (9,885) |
Commercial construction |  | — |  |  |  | — |  |  |  | — |
Business banking |  | 1,492 |  |  |  | 430 |  |  |  | 1,062 |
Consumer real estate |  | 1,448 |  |  |  | 2,319 |  |  |  | (871) |
Other Consumer |  | — |  |  |  | — |  |  |  | — |
Total Nonperforming Troubled Debt Restructurings |  | 14,033 |  |  |  | 29,288 |  |  |  | (15,255) |
Total Nonperforming Loans(1) |  | 111,312 |  |  |  | 146,774 |  |  |  | (35,462) |
OREO |  | 13,370 |  |  |  | 2,155 |  |  |  | 11,215 |
Total Nonperforming Assets |  | $ | 124,682 |  |  |  | $ | 148,929 |  |  |  | $ | (24,247) |
Asset Quality Ratios: |  |  |  |  |  |  |  |
Nonperforming loans as a percent of total portfolio loans |  | 1.60 | % |  |  | 2.03 | % |  |  |
Nonperforming assets as a percent of total portfolio loans plus OREO |  | 1.78 | % |  |  | 2.06 | % |  |  |
(1) Included in nonperforming commercial loans is $1.7 million of loans held for sale

Our policy is to place loans in all categories in nonaccrual status when collection of interest or principal is doubtful, or generally when interest or principal payments are 90 days or more past the contractual due date. Nonperforming loans decreased $35.5 million to $111.3 million at September 30, 2021 compared to $146.8 million at December 31, 2020. The significant decrease in nonperforming loans primarily related to the payoff of three CRE relationships for a total of $14.4 million, charge-offs of four commercial relationships for a total of $14.3 million, two loans moving to OREO for a total of $12.2 million and two CRE hotel loans returning to performing status for a total of $11.8 million. Offsetting the decrease in nonperforming loans was the addition of a $21.7 million C&I loans during the three months ended September 30, 2021.
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Item 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS
Deposits

(dollars in thousands) | September 30, 2021 |  | December 31, 2020 |  | $ Change
Customer Deposits |  |  |  |  |  |  |  |
Noninterest-bearing demand |  | $ | 2,652,314 |  |  |  | $ | 2,261,994 |  |  |  | $ | 390,320 |
Interest-bearing demand |  | 971,321 |  |  |  | 864,510 |  |  |  | 106,811 |
Money market |  | 2,045,320 |  |  |  | 1,887,051 |  |  |  | 158,269 |
Savings |  | 1,074,896 |  |  |  | 969,508 |  |  |  | 105,388 |
Certificates of deposit |  | 1,196,268 |  |  |  | 1,369,239 |  |  |  | (172,971) |
Total Customer Deposits |  | 7,940,119 |  |  |  | 7,352,302 |  |  |  | 587,817 |
Brokered Deposits |  |  |  |  |  |  |  |
Money market |  | — |  |  |  | 50,012 |  |  |  | (50,012) |
Certificates of deposit |  | 5,000 |  |  |  | 18,224 |  |  |  | (13,224) |
Total Brokered Deposits |  | 5,000 |  |  |  | 68,236 |  |  |  | (63,236) |
Total Deposits |  | $ | 7,945,119 |  |  |  | $ | 7,420,538 |  |  |  | $ | 524,581 |

Deposits are our primary source of funds. We believe that our deposit base is stable and that we have the ability to attract new deposits. Total deposits increased $524.6 million, or 7.1 percent, at September 30, 2021 compared to December 31, 2020. Total customer deposits increased $587.8 million from December 31, 2020. The increase in customer deposits is primarily related to government stimulus programs, PPP loans and our customers’ liquidity preferences. Total brokered deposits decreased $63.2 million from December 31, 2020 due to a reduced need for this funding given the customer deposit growth. Brokered deposits are an additional source of funds utilized by ALCO as a way to diversify funding sources, as well as manage our funding costs and structure.
Borrowings

(dollars in thousands) | September 30, 2021 |  | December 31, 2020 |  | $ Change |
Securities sold under repurchase agreements |  | $ | 72,586 |  |  |  | $ | 65,163 |  |  |  | $ | 7,423 |  |
Short-term borrowings |  | — |  |  |  | 75,000 |  |  |  | (75,000) |  |
Long-term borrowings |  | 22,693 |  |  |  | 23,681 |  |  |  | (988) |  |
Junior subordinated debt securities |  | 64,128 |  |  |  | 64,083 |  |  |  | 45 |  |
Total Borrowings |  | $ | 159,407 |  |  |  | $ | 227,927 |  |  |  | $ | (68,520) |  |

Borrowings are an additional source of funding for us. Total borrowings decreased $68.5 million compared to December 31, 2020 due to increased customer deposits. Total short-term borrowings decreased $75.0 million, compared to December 31, 2020. We prepaid a $9.8 million junior subordinated debt security with a rate of 4.25% on October 1, 2021.
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Item 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS
Information pertaining to short-term borrowings is summarized in the tables below for the nine months ended September 30, 2021 and for the twelve months ended December 31, 2020.

| Securities Sold Under Repurchase Agreements
(dollars in thousands) | September 30, 2021 |  | December 31, 2020
Balance at the period end | $ | 72,586 |  |  | $ | 65,163 |
Average balance during the period | $ | 67,872 |  |  | $ | 57,673 |
Average interest rate during the period | 0.12 | % |  | 0.29 | %
Maximum month-end balance during the period | $ | 73,591 |  |  | $ | 92,159 |
Average interest rate at the period end | 0.10 | % |  | 0.25 | %
| Short-Term Borrowings
(dollars in thousands) | September 30, 2021 |  | December 31, 2020
Balance at the period end | $ | — |  |  | $ | 75,000 |
Average balance during the period | $ | 8,425 |  |  | $ | 155,753 |
Average interest rate during the period | 0.19 | % |  | 0.92 | %
Maximum month-end balance during the period | $ | 25,000 |  |  | $ | 410,240 |
Average interest rate at the period end | — | % |  | 0.19 | %

Information pertaining to long-term borrowings is summarized in the tables below for the nine months ended September 30, 2021 and for the twelve months ended December 31, 2020.

| Long-Term Borrowings
(dollars in thousands) | September 30, 2021 |  | December 31, 2020
Balance at the period end | $ | 22,693 |  |  | $ | 23,681 |
Average balance during the period | $ | 23,139 |  |  | $ | 47,953 |
Average interest rate during the period | 2.00 | % |  | 2.50 | %
Maximum month-end balance during the period | $ | 23,549 |  |  | $ | 50,635 |
Average interest rate at the period end | 1.96 | % |  | 2.03 | %
| Junior Subordinated Debt Securities
(dollars in thousands) | September 30, 2021 |  | December 31, 2020
Balance at the period end | $ | 64,128 |  |  | $ | 64,083 |
Average balance during the period | $ | 64,103 |  |  | $ | 64,092 |
Average interest rate during the period | 3.05 | % |  | 3.57 | %
Maximum month-end balance during the period | $ | 64,128 |  |  | $ | 64,848 |
Average interest rate at the period end | 2.87 | % |  | 3.01 | %

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Item 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS
Liquidity and Capital Resources
Liquidity is defined as a financial institution’s ability to meet its cash and collateral obligations at a reasonable cost. This includes the ability to satisfy the financial needs of depositors who want to withdraw funds or of borrowers needing to access funds to meet their credit needs. In order to manage liquidity risk, our Board of Directors has delegated authority to ALCO for the formulation, implementation, and oversight of liquidity risk management for S&T. The ALCO’s goal is to maintain adequate levels of liquidity at a reasonable cost to meet funding needs in both a normal operating environment and for potential liquidity stress events. The ALCO monitors and manages liquidity through various ratios, reviewing cash flow projections, performing stress tests and having a detailed contingency funding plan. The ALCO policy guidelines define graduated risk tolerance levels. If our liquidity position moves to a level that has been defined as high risk, specific actions are required, such as increased monitoring or the development of an action plan to reduce the risk position.
Our primary funding and liquidity source is a stable customer deposit base. We believe S&T has the ability to retain existing and attract new deposits, mitigating any funding dependency on other more volatile sources. Refer to the "Financial Condition-Deposits" section of this MD&A, for additional discussion on deposits. Although deposits are the primary source of funds, we have identified various other funding sources that can be used as part of our normal funding program when either a structure or cost efficiency has been identified. Additional funding sources accessible to S&T include borrowing availability at the Federal Home Loan Bank, or FHLB, of Pittsburgh, federal funds lines with other financial institutions, the brokered deposit market and borrowing availability through the Federal Reserve Borrower-In-Custody program.
An important component of our ability to effectively respond to potential liquidity stress events is maintaining a cushion of highly liquid assets. Highly liquid assets are those that can be converted to cash quickly, with little or no loss in value, to meet financial obligations. ALCO policy guidelines define a ratio of highly liquid assets to total assets by graduated risk tolerance levels of minimal, moderate, and high. At September 30, 2021, we had $1.3 billion in highly liquid assets, which consisted of $855.6 million in interest-bearing deposits with banks, $434.0 million in unpledged securities and $4.3 million in loans held for sale. This resulted in a highly liquid assets to total assets ratio of 13.7 percent at September 30, 2021. Also, at September 30, 2021, we had remaining borrowing availability of $2.5 billion with the FHLB of Pittsburgh. For more information regarding our outstanding borrowings refer to the "Financial Condition- Borrowings" section of this MD&A for more details.
The following table summarizes capital amounts and ratios for S&T and S&T Bank for the dates presented:

(dollars in thousands) | Adequately Capitalized | Well- Capitalized |  | September 30, 2021 |  | December 31, 2020
| Amount | Ratio |  | Amount | Ratio
S&T Bancorp, Inc. |  |  |  |  |  |  |  |
Tier 1 leverage | 4.00 | % | 5.00 | % |  | $ | 881,306 |  | 9.65 | % |  | $ | 825,515 |  | 9.43 %
Common equity tier 1 to risk-weighted assets | 4.50 | % | 6.50 | % |  | 852,306 |  | 12.07 | % |  | 796,515 |  | 11.33 %
Tier 1 capital to risk-weighted assets | 6.00 | % | 8.00 | % |  | 881,306 |  | 12.48 | % |  | 825,515 |  | 11.74 %
Total capital to risk-weighted assets | 8.00 | % | 10.00 | % |  | 992,685 |  | 14.06 | % |  | 944,686 |  | 13.44 %
S&T Bank |  |  |  |  |  |  |  |
Tier 1 leverage | 4.00 | % | 5.00 | % |  | $ | 856,926 |  | 9.39 | % |  | $ | 810,636 |  | 9.27 %
Common equity tier 1 to risk-weighted assets | 4.50 | % | 6.50 | % |  | 856,926 |  | 12.15 | % |  | 810,636 |  | 11.55 %
Tier 1 capital to risk-weighted assets | 6.00 | % | 8.00 | % |  | 856,926 |  | 12.15 | % |  | 810,636 |  | 11.55 %
Total capital to risk-weighted assets | 8.00 | % | 10.00 | % |  | 962,456 |  | 13.64 | % |  | 922,007 |  | 13.14 %

On March 27, 2020, the regulators issued interim final rule, or IFR, “Regulatory Capital Rule: Revised Transition of the Current Expected Credit Losses Methodology for Allowances” in response to the disrupted economic activity due to the COVID-19 pandemic. The IFR provides financial institutions that adopted CECL during 2020 with the option to delay for two years the estimated impact of CECL on regulatory capital, followed by a three-year transition period to phase out the aggregate amount of the capital benefit provided by the initial two-year delay (“five-year transition”). We adopted CECL effective January 1, 2020 and elected to implement the five-year transition.
We have filed a shelf registration statement on Form S-3 under the Securities Act of 1933, as amended, with the SEC, which allows for the issuance of a variety of securities including debt and capital securities, preferred and common stock and warrants. We may use the proceeds from the sale of securities for general corporate purposes, which could include investments at the holding company level, investing in, or extending credit to subsidiaries, possible acquisitions and stock repurchases. As of September 30, 2021, we had not issued any securities pursuant to this shelf registration statement.
S&T is monitoring and will continue to monitor the impact of the pandemic and has taken and will continue to take steps to mitigate the potential risks and impact on our liquidity and capital resources. Due to the economic uncertainty, we are taking a prudent approach to capital management.
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Item 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK
Market risk is defined as the degree to which changes in interest rates, foreign exchange rates, commodity prices or equity prices can adversely affect a financial institution’s earnings or capital. For most financial institutions, including S&T, market risk primarily reflects exposures to changes in interest rates. Interest rate fluctuations affect earnings by changing net interest income and other interest-sensitive income and expense levels. Interest rate changes also affect capital by changing the net present value of a bank’s future cash flows, and the cash flows themselves, as rates change. Accepting this risk is a normal part of banking and can be an important source of profitability and enhancing shareholder value. However, excessive interest rate risk can threaten a bank’s earnings, capital, liquidity and solvency. Our sensitivity to changes in interest rate movements is continually monitored by the Asset and Liability Committee, or ALCO. The ALCO monitors and manages market risk through rate shock analyses, economic value of equity, or EVE, analyses and by performing stress tests and simulations to mitigate earnings and market value fluctuations due to changes in interest rates.
Rate shock analyses results are compared to a base case to provide an estimate of the impact that market rate changes may have on 12 and 24 months of pretax net interest income. The base case and rate shock analyses are performed on a static balance sheet. A static balance sheet is a no growth balance sheet in which all maturing and/or repricing cash flows are reinvested in the same product at the existing product spread. Rate shock analyses assume an immediate parallel shift in market interest rates and also include management assumptions regarding the impact of interest rate changes on non-maturity deposit products (noninterest-bearing demand, interest-bearing demand, money market and savings) and changes in the prepayment behavior of loans and securities with optionality. S&T policy guidelines limit the change in pretax net interest income over 12 and 24 month horizons using rate shocks in increments of +/- 100 basis points. Policy guidelines define the percentage change in pretax net interest income by graduated risk tolerance levels of minimal, moderate and high. We have temporarily suspended the analyses on downward rate shocks of 200 basis points or more because they do not provide meaningful insight into our interest rate risk position.
In order to monitor interest rate risk beyond the 24 month time horizon of rate shocks on pretax net interest income, we also perform EVE analyses. EVE represents the present value of all asset cash flows minus the present value of all liability cash flows. EVE change results are compared to a base case to determine the impact that market rate changes may have on our EVE. As with rate shock analyses on pretax net interest income, EVE analyses incorporate management assumptions regarding prepayment behavior of fixed rate loans and securities with optionality and the behavior and value of non-maturity deposit products. S&T policy guidelines limit the change in EVE using rate shocks in increments of +/- 100 basis points. Policy guidelines define the percentage change in EVE by graduated risk tolerance levels of minimal, moderate and high. We have also temporarily suspended the downward rate shocks of 200 basis points or more for EVE.
The table below reflects the rate shock analyses results for the 1-12 and 13-24 month periods of pretax net interest income and EVE.

| September 30, 2021 |  | December 31, 2020
| 1 - 12 Months |  | 13 - 24 Months |  | % Change in EVE |  | 1 - 12 Months |  | 13 - 24 Months |  | % Change in EVE
Change in Interest Rate (basis points) | % Change in Pretax Net Interest Income |  | % Change in Pretax Net Interest Income |  |  | % Change in Pretax Net Interest Income |  | % Change in Pretax Net Interest Income |
400 | 29.5 |  | 37.3 |  | 20.3 |  | 15.8 |  | 28.5 |  | 28.5
300 | 21.9 |  | 27.8 |  | 21.4 |  | 11.7 |  | 21.3 |  | 29.0
200 | 14.5 |  | 18.8 |  | 19.6 |  | 7.7 |  | 14.3 |  | 25.6
100 | 6.8 |  | 9.2 |  | 12.5 |  | 4.4 |  | 8.0 |  | 17.7
-100 | (4.5) |  |  | (8.3) |  |  | (27.0) |  |  | (2.8) |  |  | (5.7) |  |  | (28.2) |

The results from the rate shock analyses on net interest income are consistent with having an asset sensitive balance sheet. Having an asset sensitive balance sheet means more assets than liabilities will reprice during the measured time frames. The implications of an asset sensitive balance sheet will differ depending upon the change in market interest rates. For example, with an asset sensitive balance sheet in a declining interest rate environment, more assets than liabilities will decrease in rate. This situation could result in a decrease in net interest income and operating income. Conversely, with an asset sensitive balance sheet in a rising interest rate environment, more assets than liabilities will increase in rate. This situation could result in an increase in net interest income and operating income.
Our rate shock analyses show an improvement in the percentage change in pretax net interest income in the rates up scenarios and a decline in the rates down scenarios when comparing September 30, 2021 to December 31, 2020. We have become more asset sensitive due to our increased balances at the Federal Reserve. Our EVE analyses show a decline in the percentage change in EVE in the rates up scenarios and an improvement in the rates down scenario when comparing September 30, 2021 to December 31, 2020. The EVE decline is due to the impact of a steepened yield curve on the value of non-maturity deposits.
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Item 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK
In addition to rate shocks and EVE analyses, we perform a market risk stress test at least annually. The market risk stress test includes sensitivity analyses and simulations. Sensitivity analyses are performed to help us identify which model assumptions cause the greatest impact on pretax net interest income. Sensitivity analyses may include changing prepayment behavior of loans and securities with optionality and the impact of interest rate changes on non-maturity deposit products. Simulation analyses may include the potential impact of rate changes other than the policy guidelines, yield curve shape changes, significant balance mix changes and various growth scenarios.
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Item 4. CONTROLS AND PROCEDURES
Evaluation of Disclosure Controls and Procedures
Under the supervision and with the participation of S&T’s Chief Executive Officer, or CEO, and Chief Financial Officer, or CFO (its principal executive officer and principal financial officer, respectively), management has evaluated the effectiveness of the design and operation of S&T’s disclosure controls and procedures as of September 30, 2021. In designing and evaluating the disclosure controls and procedures, management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving the desired control objectives. We maintain disclosure controls and procedures that are designed to ensure that information required to be disclosed by us in the reports that we file or submit under the Securities Exchange Act of 1934, as amended, or the Exchange Act, is recorded, processed, summarized and reported within the time periods required by the Securities and Exchange Commission, or the SEC, and that such information is accumulated and communicated to S&T’s management, including our CEO and CFO, as appropriate to allow timely decisions regarding required disclosure.
Based on and as of the date of such evaluation, our CEO and CFO concluded that the design and operation of our disclosure controls and procedures were effective in all material respects, as of the end of the period covered by this report.
Changes in Internal Control over Financial Reporting
During the quarter ended September 30, 2021, there were no changes made to S&T’s internal control over financial reporting (as defined in Rule 13a-15(f) under the Exchange Act) that materially affected, or are reasonably likely to materially affect, S&T’s internal control over financial reporting.
PART II
OTHER INFORMATION
Item 1. Legal Proceedings
None
Item 1A. Risk Factors
There have been no material changes to the risk factors that we have previously disclosed in Part I, Item 1A – “Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2020, as filed with the SEC on March 1, 2021 other than the risks described below.
Risks Related to Our Business Strategy
Our future performance will depend, in part, on the successful transition of our new CEO.
Christopher J. McComish was appointed Chief Executive Officer (CEO) of S&T and S&T Bank, effective August 23, 2021 (the “Effective Date”) and was appointed to the Boards of Directors of S&T and S&T Bank on the Effective Date. David G. Antolik, who served as Interim Chief Executive Officer since April 2021 through the Effective Date, continues to serve as President of S&T and S&T Bank and as a member of the Boards of Directors of S&T and S&T Bank. Our future performance will depend, in part, on the successful transition of our new CEO. This transition may be disruptive to our business, and if we are unable to execute an orderly transition and successfully integrate our new CEO into our management team, our revenue, results of operations, and financial condition may be adversely affected. Further, if our new CEO formulates different or changed views, the future strategy and plans of S&T may differ materially from those of the past.
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Item 2. Unregistered Sales of Equity Securities and Use of Proceeds
Purchases of Equity Securities
The following table is a summary of our purchases of common stock during the third quarter of 2021:

Period |  | Total number of shares purchased |  | Average price paid per share |  | Total number of shares purchased as part of publicly announced plan(1) |  | Approximate dollar value of shares that may yet be purchased under the plan |
|  |  |  |  |  |  |  | $37,441,683 |  |
07/01/2021 - 07/31/2021 |  | — |  |  | $— |  |  | — |  |  | 37,441,683 |  |
08/01/2021 - 08/31/2021 |  | — |  |  | — |  |  | — |  |  | 37,441,683 |  |
09/01/2021 - 09/30/2021 |  | — |  |  | — |  |  | — |  |  | 37,441,683 |  |
Total |  | — |  |  | $— |  |  | — |  |  | $37,441,683 |  |

(1) On March 15, 2021, our Board of Directors authorized an extension of the $50 million share repurchase plan, which was set to expire March 31, 2021. This authorization extended the expiration date of the repurchase plan through March 31, 2022. The plan permits S&T to repurchase from time to time up to the previously authorized $50 million in aggregate value of shares of S&T's common stock, with $37.4 million of capacity remaining at September 30, 2021, through a combination of open market and privately negotiated repurchases. The specific timing, price and quantity of repurchases will be at the discretion of S&T and will depend on a variety of factors, including general market conditions, the trading price of common stock, legal and contractual requirements, applicable securities laws and S&T's financial performance. The repurchase plan does not obligate us to repurchase any particular number of shares. We expect to fund repurchases from cash on hand and internally generated funds. Share repurchases will not occur unless permissible under applicable laws.
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Item 3. Defaults Upon Senior Securities
None
Item 4. Mine Safety Disclosures
Not Applicable
Item 5. Other Information
None
Item 6. Exhibits

2.1 | Agreement and Plan of Merger, dated June 5, 2019, by and between DNB Financial Corporation and S&T Bancorp, Inc. Filed as Exhibit 2.1 to S&T Bancorp, Inc. Current Report on Form 8-K filed on June 5, 2019, and incorporated herein by reference. |
3.1 | Amended and Restated Articles of Incorporation of S&T Bancorp, Inc. Filed as Exhibit 3.1 to S&T Bancorp, Inc. Quarterly Report on Form 10-Q filed for the quarter ended June 30, 2021 filed on August 4, 2021, and incorporated herein by reference. |
31.1 | Rule 13a-14(a) Certification of the Chief Executive Officer. |
31.2 | Rule 13a-14(a) Certification of the Chief Financial Officer. |
32 | Rule 13a-14(b) Certification of the Chief Executive Officer and Chief Financial Officer. |
101.INS | XBRL Instance Document - the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document |
101.SCH | XBRL Taxonomy Extension Schema |
101.CAL | XBRL Taxonomy Extension Calculation Linkbase |
101.DEF | XBRL Taxonomy Extension Definition Linkbase |
101.LAB | XBRL Taxonomy Extension Label Linkbase |
101.PRE | XBRL Taxonomy Extension Presentation Linkbase |
104 | Cover Page Interactive Data File (formatted as Inline XBRL and contained in Exhibits 101) |

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SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

| S&T Bancorp, Inc. (Registrant)
November 3, 2021 | /s Mark Kochvar
| Mark Kochvar Senior Executive Vice President and Chief Financial Officer (Principal Financial Officer and Duly Authorized Signatory)

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