We sold fixed-rate mortgage loans held for sale with principal balances of $827,000 and $5.4 million during the nine months ended September 30, 2023 and 2022, respectively. Federal Home Loan Bank advances had a net increase of $115.0 million to $256.0 million during the nine months ended September 30, 2023 and remained constant at $141.0 million during the nine months ended September 30, 2022. Securities sold under agreements to repurchase remained constant at $10.0 million during the nine months ended September 30, 2023 and 2022.
Our investments in mortgage-backed securities have been issued by Freddie Mac or Fannie Mae, which are U.S. government-sponsored enterprises, or Ginnie Mae, which is a U.S. government agency. These entities guarantee the payment of principal and interest on our mortgage-backed securities. As of September 30, 2023 and December 31, 2022, we owned $714.8 million and $738.6 million, respectively, of mortgage-backed securities issued by Freddie Mac, Fannie Mae, and Ginnie Mae.
Critical Accounting Policies
On January 1, 2023, we adopted ASU 2016-13, “Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments,” which created material changes to our critical accounting policies that existed at December 31, 2022. This standard replaces the “incurred loss” model, which estimates a loss allowance based on current known and inherent losses within a loan portfolio to an “expected loss” model known as CECL, which estimates a loss based on losses expected to be recorded over the life of the loan portfolio.
The estimate of the ACL under CECL is based on relevant information about past events, current conditions, and reasonable and supportable forecasts that affect the collectability of cash flows. Refer to Note (2) Summary of Significant Accounting Policies in the accompanying Notes to the Consolidated Financial Statements in this report for further discussions on the risk factors considered by management in establishing the ACL.
Comparison of Financial Condition at September 30, 2023 and December 31, 2022
Assets. Our total assets increased by $41.6 million, or 1.9%, to $2.2 billion at September 30, 2023. The increase in assets was primarily due to a $48.6 million increase in cash and an $11.7 million increase in total loans, which were partially offset by a $23.8 million decrease in total investment securities.
Cash and Cash Equivalents. Cash and cash equivalents were $89.1 million at September 30, 2023, an increase of $48.6 million, or 119.8%, since December 31, 2022. The increase in cash and cash equivalents was primarily caused by a $115.0 million increase in borrowings, which was partially offset by a $65.1 million decrease in deposits, each as described below.
Loans. Total loans were $1.3 billion at September 30, 2023, or 59.1% of total assets. During the nine months ended September 30, 2023, the loan portfolio increased by $11.7 million, or 0.9%. The increase in the loan portfolio primarily occurred as the origination of new loans exceeded principal repayments and loan sales.
Securities. Total investment securities, including $19.1 million of investment securities available for sale, were $714.8 million at September 30, 2023, or 32.3% of total assets. During the nine months ended September 30, 2023, the investment securities portfolio decreased by $23.8 million, or 3.2%. The decrease in the investment securities balance occurred as principal repayments exceeded purchases.
At September 30, 2023, none of the underlying collateral for the securities consisted of subprime or Alt-A (traditionally defined as nonconforming loans having less than full documentation) loans.
Deposits. Deposits were $1.7 billion at September 30, 2023, a decrease of $65.1 million, or 3.8%, since December 31, 2022. The decrease in deposits was primarily due to decreases of $146.4 million in passbook savings accounts and $13.2 million in checking accounts that was partially offset by a $96.8 million increase in certificates of deposit. The changes in deposits occurred primarily as customers transferred funds from savings and checking accounts for higher interest rates paid on our certificates of deposit or sought higher interest rates on their deposits than what we offer.