Summary of Significant Accounting Policies	9 Months Ended
Sep. 30, 2019
Summary of Significant Accounting Policies
Summary of Significant Accounting Policies	Note 1 – Summary of Significant Accounting Policies The accounting policies followed in the preparation of the interim consolidated financial statements are consistent with those used in the preparation of the annual financial information. The interim consolidated financial statements reflect all normal and recurring adjustments that are necessary, in the opinion of management, for a fair statement of results for the interim period presented. Results for the period ended September 30, 2019, are not necessarily indicative of the results that may be expected for the year ending December 31, 2019. These interim consolidated financial statements are unaudited and should be read in conjunction with the audited financial statements and notes included in Old Second Bancorp, Inc.’s (the “Company”) annual report on Form 10-K for the year ended December 31, 2018. Unless otherwise indicated, amounts in the tables contained in the notes to the consolidated financial statements are in thousands. Certain items in prior periods have been reclassified to conform to the current presentation. The Company’s consolidated financial statements are prepared in accordance with United States generally accepted accounting principles (“GAAP”) and follow general practices within the banking industry. Application of these principles requires management to make estimates, assumptions, and judgments that affect the amounts reported in the consolidated financial statements and accompanying notes. These estimates, assumptions, and judgments are based on information available as of the date of the consolidated financial statements. Future changes in information may affect these estimates, assumptions, and judgments, which, in turn, may affect amounts reported in the consolidated financial statements. Significant accounting policies are presented in Note 1 to the consolidated financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018. These policies, along with the disclosures presented in the other financial statement notes and in this discussion, provide information on how significant assets and liabilities are valued in the consolidated financial statements and how those values are determined. Recent Accounting Pronouncements In February 2016, the FASB issued ASU No. 2016-02 “Leases (Topic 842).” This ASU was issued to increase transparency and comparability among organizations by recognizing lease assets and liabilities on the balance sheet and disclosing key information about leasing arrangements. One key revision from prior guidance was to include operating leases within assets and liabilities recorded; another revision was to create a new model to follow for sale-leaseback transactions. The impact of this pronouncement will primarily affect lessees, as virtually all of their assets will be recognized on the balance sheet, by recording a right of use asset and lease liability. This pronouncement is effective for fiscal years beginning after December 15, 2018. In July 2018, the FASB issued ASU No. 2018-11, “Leases (Topic 842): Targeted Improvements” which provided additional guidance on the transition method, including application as a cumulative-effect adjustment to equity and practical expedients to use when accounting for lease components. The Company adopted this standard as of January 1, 2019, and recorded right of use assets of $817,000 with a like lease liability. As of September 30, 2019, the right of use assets and lessee lease liability both totaled $3.3 million. The Company also recorded leases receivable related to lessor leases of $174,000 as of January 1, 2019 with a like entry to lease liabilities for the lessor position; these tenant leases receivable balances and lessor lease liabilities both totaled approximately $97,000 as of September 30, 2019. There was no impact to equity for the adoption of this standard on a modified retrospective basis. In June 2016, the FASB issued ASU No. 2016-13 “Measurement of Credit Losses on Financial Instruments (Topic 326).” This ASU was issued to provide financial statement users with more useful information about the expected credit losses on financial instruments and other commitments to extend credit held by a reporting entity at each reporting date to enhance the decision making process. The new methodology to be used should reflect expected credit losses based on relevant vintage historical information, supported by reasonable forecasts of projected loss given defaults, which will affect the collectability of the reported amounts. This new methodology will also require available-for-sale debt securities to have a credit loss recorded through an allowance rather than write-downs. ASU 2016-13 is effective for financial statements issued for fiscal years beginning after December 15, 2019. The Company is assessing the impact of ASU 2016-13 on its accounting and disclosures, and has determined that a combination of loss rate models utilizing weighted average remaining life, migration and vintage analysis will be used for calculation of future expected losses based on data availability and the characteristics of each loan pool being assessed upon the ASU’s adoption in 2020. The Company has accumulated historical data by loan pools and collateral classifications, and is reviewing and refining the parallel calculation performed as of September 30, 2019, to confirm the model processes and determine financial statement impact prior to adoption in 2020. The Company is also developing internal control processes and disclosure documentation related to adoption of this standard. Subsequent Events On October 15, 2019, the Company’s Board of Directors declared a cash dividend of $0.01 per share payable on November 4, 2019, to stockholders of record as of October 25, 2019; dividends of $299,000 were paid to stockholders on November 4, 2019.

Note 1 – Summary of Significant Accounting Policies

The accounting policies followed in the preparation of the interim consolidated financial statements are consistent with those used in the preparation of the annual financial information. The interim consolidated financial statements reflect all normal and recurring adjustments that are necessary, in the opinion of management, for a fair statement of results for the interim period presented. Results for the period ended September 30, 2019, are not necessarily indicative of the results that may be expected for the year ending December 31, 2019. These interim consolidated financial statements are unaudited and should be read in conjunction with the audited financial statements and notes included in Old Second Bancorp, Inc.’s (the “Company”) annual report on Form 10-K for the year ended December 31, 2018. Unless otherwise indicated, amounts in the tables contained in the notes to the consolidated financial statements are in thousands. Certain items in prior periods have been reclassified to conform to the current presentation.

The Company’s consolidated financial statements are prepared in accordance with United States generally accepted accounting principles (“GAAP”) and follow general practices within the banking industry. Application of these principles requires management to make estimates, assumptions, and judgments that affect the amounts reported in the consolidated financial statements and accompanying notes. These estimates, assumptions, and judgments are based on information available as of the date of the consolidated financial statements. Future changes in information may affect these estimates, assumptions, and judgments, which, in turn, may affect amounts reported in the consolidated financial statements.

Significant accounting policies are presented in Note 1 to the consolidated financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018. These policies, along with the disclosures presented in the other financial statement notes and in this discussion, provide information on how significant assets and liabilities are valued in the consolidated financial statements and how those values are determined.

Recent Accounting Pronouncements

In February 2016, the FASB issued ASU No. 2016-02 “Leases (Topic 842).” This ASU was issued to increase transparency and comparability among organizations by recognizing lease assets and liabilities on the balance sheet and disclosing key information about leasing arrangements. One key revision from prior guidance was to include operating leases within assets and liabilities recorded; another revision was to create a new model to follow for sale-leaseback transactions. The impact of this pronouncement will primarily affect lessees, as virtually all of their assets will be recognized on the balance sheet, by recording a right of use asset and lease liability. This pronouncement is effective for fiscal years beginning after December 15, 2018. In July 2018, the FASB issued ASU No. 2018-11, “Leases (Topic 842): Targeted Improvements” which provided additional guidance on the transition method, including application as a cumulative-effect adjustment to equity and practical expedients to use when accounting for lease components. The Company adopted this standard as of January 1, 2019, and recorded right of use assets of $817,000 with a like lease liability. As of September 30, 2019, the right of use assets and lessee lease liability both totaled $3.3 million. The Company also recorded leases receivable related to lessor leases of $174,000 as of January 1, 2019 with a like entry to lease liabilities for the lessor position; these tenant leases receivable balances and lessor lease liabilities both totaled approximately $97,000 as of September 30, 2019. There was no impact to equity for the adoption of this standard on a modified retrospective basis.

In June 2016, the FASB issued ASU No. 2016-13 “Measurement of Credit Losses on Financial Instruments (Topic 326).” This ASU was issued to provide financial statement users with more useful information about the expected credit losses on financial instruments and other commitments to extend credit held by a reporting entity at each reporting date to enhance the decision making process. The new methodology to be used should reflect expected credit losses based on relevant vintage historical information, supported by reasonable forecasts of projected loss given defaults, which will affect the collectability of the reported amounts. This new methodology will also require available-for-sale debt securities to have a credit loss recorded through an allowance rather than write-downs. ASU 2016-13 is effective for financial statements issued for fiscal years beginning after December 15, 2019. The Company is assessing the impact of ASU 2016-13 on its accounting and disclosures, and has determined that a combination of loss rate models utilizing weighted average remaining life, migration and vintage analysis will be used for calculation of future expected losses based on data availability and the characteristics of each loan pool being assessed upon the ASU’s adoption in 2020. The Company has accumulated historical data by loan pools and collateral classifications, and is reviewing and refining the parallel calculation performed as of September 30, 2019, to confirm the model processes and determine financial statement impact prior to adoption in 2020. The Company is also developing internal control processes and disclosure documentation related to adoption of this standard.

Subsequent Events

On October 15, 2019, the Company’s Board of Directors declared a cash dividend of $0.01 per share payable on November 4, 2019, to stockholders of record as of October 25, 2019; dividends of $299,000 were paid to stockholders on November 4, 2019.