Paul Frenkiel
Analyst · KBW
Thank you, Damian. Return on assets and equity for fourth quarter 2021 were, respectively, 1.7% and 17% compared to 1.6% and 17% in Q4 2020. Net interest income in Q4 2021 was comparable to Q4 2020 at $52 million. In the third quarter of 2021, you'll recall that we resumed the origination of non-SBA commercial real estate loans, which are intended to offset the impact of prepayments and payoffs on such loans originally generated for sale.
While there were approximately $500 million of such originations in Q4 2021, their impact on interest income was partially offset by approximately $4 million as a result of prepayments on the loans originally generated for resale.
However, fees related to those prepayments are recorded in net realized and unrealized gains on commercial loans, which increased $4.5 million in Q4 2021 compared to Q4 2020. Even with the impact of the CRE prepayments, year-end 2021 period end loans and loans at fair value increased 14% over year-end 2020. Interest income in Q4 2021 reflected a reduction of $3.5 million in securities interest compared to Q4 2020, reflecting lower securities balances, prepayments of higher-yielding securities and lower reinvestment rates.
Our interest expense was reduced from 24 basis points during Q4 2020 to 19 basis points during Q4 2021. Most of our deposit interest expense is contractually tied to a portion of changes in market interest rates. Our net interest margin of 3.51% for Q4 2021 was slightly down from 3.58% in Q4 2020. The reduction reflected a lower yield on the securities portfolio as higher-yielding securities matured or prepaid.
While yields on loans were also lower, they comprised a greater portion of interest-earning assets in 2021, which contributed positively to the 2021 margin. In the third quarter of 2021, recall that our NIM was 3.35%, which reflected higher balances at the Federal Reserve, earning nominal rates.
The provision for credit losses increased to $1.6 million in Q4 2021 from $554,000 in Q4 2020. The increase reflected the impact of loan growth on the CECL model, including real estate bridge loans, which grew almost $500 million during Q4 2021. Because SBLOC and IBLOC loans are respectively collateralized by marketable securities and the cash value of life insurance and have incurred only nominal credit losses, management excludes those loans from the ratio of the allowance to total loans in its internal analysis. We believe our loan portfolios generally are lower risk than other forms of lending as a result of their charge-off history, which reflects the nature of related collateral.
Our non-SBA CRE loans at fair value and within real estate bridge lending are comprised primarily of apartment buildings, while our SBLOC and IBLOC portfolios are respectively collateralized by marketable securities with a cash value of life insurance. Our small business loan portfolio is comprised primarily of SBA loans, which are either 75% government guaranteed or have 50% to 60% origination date loan-to-value. For our leasing portfolio, we have recourse to underlying vehicles in a prolonged history of pricing leases to minimize losses. Tables contained in the earnings press release detail diversification of our loan portfolios.
Prepaid debit and other payment-related accounts are our largest funding source and the primary driver of noninterest income. Total fees and related payments income in Q4 2021 were comparable to Q4 2020 as the exit of a client relationship offset growth in other relationships. Noninterest expense for Q4 2021 was $43 million, reflecting an increase of $1.4 million or 3% from Q4 2020. FDIC insurance expense was $1.8 million lower, primarily reflecting the cumulative impact of a lower rate resulting from the reclassification of certain deposits from brokered to non-brokered. The largest expense increase was $1.1 million in salaries, which were 4% higher than Q4 2020.
Q4 2021 results also reflected the impact of a reduced tax rate of approximately 24% versus higher rates in recent years. The reduction resulted from excess tax deductions related to stock-based compensation. The large deductions and tax benefit resulted from the increase in the company's stock price as compared to the original grant date.
Book value per share at 2021 year-end increased 13% to $11.37, compared to $10.10 a year earlier, reflecting earnings per share and the net impact of stock repurchases. I will now turn the call back to Damian.