The provision for credit losses on loans decreased by $798,000, from an expense of $346,000 for the quarter ended June 30, 2022 to a credit of $452,000 for the current quarter. The decrease to the provision for the three months ended June 30, 2023 was primarily attributable to a decrease in loan balances, primarily indirect automobile loans, and a $710,000 loss on a commercial loan that was reserved for in the first quarter and written off in the second quarter.
Net charge-offs increased $745,000 from net recoveries of $123,000 for the second quarter of 2022 to net charge-offs of $622,000 for the second quarter of 2023. The increase was primarily due to a $710,000 charge-off of one commercial loan in the second quarter of 2023. Year-to-date, net charge-offs increased $1.1 million from net recoveries of $43,000 for the first six months of 2022 to net charge-offs of $1.0 million for the first six months of 2023. The increase was primarily due to the aforementioned commercial loan charge-off and increased charge-offs in indirect automobile loans of $354,000. The percentage of overdue account balances to total loans decreased to 1.76% as of June 30, 2023 from 2.29% as of December 31, 2022, while non-performing assets increased $73,000, or 1.7%, to $4.5 million at June 30, 2023.
Non-interest income totaled $1.4 million for the three months ended June 30, 2023, a decrease of $145,000, or 9.6%, from the comparable period in the prior year, due primarily to a decrease in the net gain on sales of mortgage loans of $241,000 as activity decreased due to fewer originations in the increasing interest rate environment and a strategic decision to hold new production in our portfolio instead of selling these loans. The decrease was also due to a decrease in investment advisory income of $129,000, primarily the result of a challenging investment market and economic conditions. These decreases were partially offset by $162,000 as the prior year period included a net realized loss on the sale of securities.
Year-to-date non-interest income totaled $2.7 million for the six months ended June 30, 2023, a decrease of $480,000, or 14.9%, from the comparable period in the prior year, due primarily to a decrease in the net gain on sales of mortgage loans as activity decreased due to fewer originations in the increasing interest rate environment and a strategic decision to hold new production in our portfolio instead of selling these loans. Gain on sales of mortgage loans decreased $631,000, or 91.1%, compared to the prior year period as we sold $2.6 million of residential mortgage loans in the first half of 2023 as compared to $18.1 million in the first half of 2022. Investment advisory income decreased $160,000, or 22.8%, primarily the result of a challenging investment market and economic conditions. These decreases were partially offset by the prior year period net realized loss on the sale of securities of $162,000.
For the second quarter of 2023, non-interest expense totaled $9.3 million, a decrease of $196,000, or 2.1%, over the comparable 2022 period. The decrease was primarily due to a decrease in salaries and benefits of $565,000, or 10.2%, as the number of employees decreased. Occupancy decreased $112,000, or 9.3%, due to a branch closure at the end of 2022. Marketing fees also decreased by $58,000. These decreases were partially offset by the increase in other non-interest expense of $195,000, or 13.8%, as well as an increase in FDIC deposit insurance assessments of $160,000, or 82.5%.
For the first six months of 2023, non-interest expense totaled $18.5 million, a decrease of $98,000, or 0.5%, over the comparable 2022 period. The decrease was primarily due to a decrease in salaries and benefits of $844,000 as the number of employees decreased when the Company made the difficult decision to layoff approximately 5% of its workforce in the first quarter of 2023. Occupancy decreased $131,000 due to the closure of our Monroe branch at the end of 2022. Marketing fees also decreased by $71,000. These decreases were partially offset due to the growth in other non-interest expense of $549,000, or 20.4%, primarily due to a decrease in deferred loan commitments and inflationary pressures on our service contracts, as well as an increases in FDIC deposit insurance assessments of $260,000, or 69.1%, and an increase in professional fees of $71,000.