The amortized cost and estimated fair value of securities available for sale along with gross unrealized gains and losses as of the dates indicated are summarized as follows:


September 30, 2024	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
U.S. government agencies and corporations	$	353,077	$	-	$	32,645	$	320,432
States and political subdivisions		178,270		-		25,542		152,728
Mortgage-backed securities		146,619		53		4,427		142,245
Corporate debt securities		6,507		-		631		5,876
U.S. treasury		999		-		9		990
Total securities available for sale	$	685,472	$	53	$	63,254	$	622,271


December 31, 2023	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
U.S. government agencies and corporations	$	353,904	$	-	$	42,060	$	311,844
States and political subdivisions		179,507		-		29,614		149,893
Mortgage-backed securities		156,875		-		6,724		150,151
Corporate debt securities		6,504		-		754		5,750
U.S. treasury		996		-		33		963
Total securities available for sale	$	697,786	$	-	$	79,185	$	618,601

No allowance for credit loss on securities available for sale was recorded as of September 30, 2024 or December 31, 2023.

Accrued interest receivable on securities, included in accrued interest receivable on the Consolidated Balance Sheets, totaled $3,379 at September 30, 2024 and $3,281 at December 31, 2023.

The deferred tax asset for the net unrealized loss on securities available for sale was $13,272 as of September 30, 2024 and $16,629 as of December 31, 2023. The deferred tax asset is included in other assets on the Consolidated Balance Sheets.

The amortized cost and fair value of single maturity securities available for sale at September 30, 2024, by contractual maturity, are shown below. Expected maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. Mortgage-backed securities included in these totals are categorized by final maturity.


	September 30, 2024
	Amortized Cost		Fair Value
Available for Sale:
Due in one year or less	$	30,957	$	30,674
Due after one year through five years		202,285		191,613
Due after five years through ten years		249,367		217,742
Due after ten years		202,863		182,242
Total securities available for sale	$	685,472	$	622,271

Information pertaining to securities with gross unrealized losses aggregated by investment category and length of time that the individual securities have been in a continuous loss position, as of the dates indicated, follows.


September 30, 2024	Less Than 12 Months				12 Months or More
	Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses
U.S. government agencies and corporations	$	-	$	-	$	320,432	$	32,645
State and political subdivisions		924		78		151,803		25,464
Mortgage-backed securities		3		-		119,869		4,427
Corporate debt securities		-		-		5,876		631
U.S. treasury		-		-		990		9
Total temporarily impaired securities	$	927	$	78	$	598,970	$	63,176


December 31, 2023	Less Than 12 Months				12 Months or More
	Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses
U.S. government agencies and corporations	$	-	$	-	$	311,844	$	42,060
State and political subdivisions		884		1		148,763		29,613
Mortgage-backed securities		1,616		26		147,922		6,698
Corporate debt securities		-		-		5,750		754
U.S. treasury		-		-		963		33
Total temporarily impaired securities	$	2,500	$	27	$	615,242	$	79,158

The Company evaluates securities available for sale that are in unrealized loss positions to determine whether the impairment is due to credit-related factors or noncredit-related factors. Consideration is given to the extent to which the fair value is less than cost, the financial condition and near-term prospects of the issuer, and the intent and ability of the Company to retain its investment in the security for a period of time sufficient to allow for any anticipated recovery in fair value.

At September 30, 2024, the Company had 563 securities with a fair value of $599,897 in an unrealized loss position. The Company reviews securities in an unrealized loss position to evaluate credit risk. The Company considers payment history, risk ratings from external parties, financial statements for municipal and corporate securities, public statements from issuers and other available credible published sources in evaluating credit risk. No credit risk was found and no ACL on securities available for sale was recorded as of September 30, 2024. The unrealized losses are attributed to noncredit-related factors, including changes in interest rates and other market conditions. The Company does not have the intent to sell any of these securities and believes that it is more likely than not that the Company will not have to sell any such securities before a recovery of cost. The contractual terms of the investments do not permit the issuers to settle the securities at a price less than the cost basis of the investments. The fair value is expected to recover as the securities approach their maturity date or repricing date or if market yields for such investments decline.

The Company holds restricted stock that is reported separately from available for sale securities. As a member of the Federal Reserve and the Federal Home Loan Bank of Atlanta (“FHLB”), NBB is required to maintain certain minimum investments in the common stock of those entities. Required levels of investment are based upon NBB’s capital and a percentage of qualifying assets. The Company purchases stock from or sells stock back to the correspondents based on their calculations. The stock is held by member institutions only and is not actively traded.

Redemption of FHLB stock is subject to certain limitations and conditions. At its discretion, the FHLB may declare dividends on the stock. In addition to dividends, NBB also benefits from its membership with FHLB through eligibility to borrow from the FHLB, using as collateral NBB’s capital stock investment in the FHLB and qualifying NBB real estate mortgage loans totaling $507,498 at September 30, 2024. The Company’s management reviews for impairment based upon the ultimate recoverability of the cost basis of the FHLB stock, and at September 30, 2024, did not determine any impairment.

The Company initiated sale of FCB’s securities portfolio upon completion of the acquisition, and no gain or loss was recorded. During the first nine months of 2023, the Company realized net securities losses of $3,332 on the sale of securities with an amortized cost basis of $46,850. The sales were part of the Company’s interest rate risk management strategy.