Loans
Loans increased $1.6 billion, or 27.5%, compared to the prior quarter, to $7.4 billion as of December 31, 2021, and increased $2.1 billion, or 39.5%, compared to December 31, 2020. The increase was impacted by the acquisition of TGR Financial, which added $1.06 billion in gross loans, or $1.05 billion of net loans held for investment after purchase accounting adjustments. Loan balances were also affected by loan fundings, which in the fourth quarter of 2021 were $1.2 billion, an increase of $411 million, or 51.2%, from the third quarter of 2021 and an increase of $498 million, or 69.6%, from the fourth quarter of 2020. Contributing to loan originations during the quarter, our C&I division funded $518 million of new commercial loans during the fourth quarter of 2021, of which 55% were adjustable commercial revolving lines of credit. The remaining C&I originations were comprised of $129 million of commercial term loans, $46 million of public finance loans, $32 million of owner occupied commercial real estate loans, and $25 million of equipment finance leases. We funded no additional PPP loans during the quarter. Loan balances during the fourth quarter of 2021 were also impacted by loan payoffs of $670 million, compared to payoffs of $583 million in the third quarter of 2021 and $534 million in the fourth quarter of 2020. The current pipeline remains very strong going into the first quarter.
Investment Securities
Investment securities increased $300 million, or 33.3%, from the prior quarter, to $1.2 billion as of December 31, 2021, and increased $387.1 million, or 47.5%, compared to December 31, 2020. The increases in the balance of investment securities compared to the third quarter of 2021 and fourth quarter of 2020 were primarily driven by securities purchases in the fourth quarter of 2021 and the result of $221.8 million of investment securities, net of the fair value adjustment, acquired in connection with the acquisition of TGR Financial.
The allowance for credit losses for investments increased by $0.3 million from the prior quarter, to $10.4 million as of December 31, 2021, from $10.1 million as of September 30, 2021, and increased $3.2 million, from $7.2 million as of December 31, 2020. The increase from the fourth quarter of 2020 was a result of the lower interest rate environment and faster than expected prepayments that negatively impacted the projected cash flows on FFB’s interest-only strip securities.
Deposits and Borrowings
Deposits were $8.8 billion as of December 31, 2021, an increase of $2.0 billion, or 28.7%, compared to the prior quarter, and an increase of $2.9 billion, or 49.0%, compared to the fourth quarter of 2020. Deposit growth during the fourth quarter of 2021 compared to the fourth quarter of 2020 was primarily driven by an increase of $1.6 billion, or 98%, in non-interest bearing demand deposits, an increase of $1.4 billion, or 157%, in interest bearing demand deposits, and an increase in money market and savings accounts of $212.9 million, largely attributable to our commercial deposit services division, and retail branches and the acquisition of TGR financial which contributed $2.2 billion of deposits after purchase accounting adjustments. The increases in deposits were offset by a reduction in CDs of $310.4 million, primarily due to our intentional run-off of higher cost brokered deposits. Noninterest-bearing demand deposits measured 37.2% of total deposits as of December 31, 2021, compared to 43.8% of total deposits as of September 30, 2021, while core deposits increased by $2.0 billion compared to the linked quarter, and measured 99% of total deposits as of December 31, 2021, and 98% of total deposits as of September 30, 2021. Commercial business deposits were 71% of total core deposits as of December 31, 2021.