Cambridge Bancorp booked a 10.9 percent increase in net income during the third quarter, owing largely to increases in its commercial and residential loan portfolios.

The parent company of Cambridge Trust Co. posted $4.4 million in net income for the period ended Sept. 30 compared with $3.9 million in the year-ago period.

“The earnings performance was driven by a sustained trend of growth in loans, which have increased by $110.5 million through the third quarter of 2015,” President and CEO Denis K. Sheahan said in a statement. “The bank recorded continued strong profitability metrics in the third quarter with return on average assets of 1.03 percent and return on average stockholders’ equity of 14.20 percent.”

Net interest income increased $1.1 million, or 9.2 percent, year-over-year to $13.2 million, largely a function of growth in the bank’s loan portfolio.

Noninterest income remained flat on a year-over-year basis at $6.5 million. The bank generated $5 million in wealth management income in the third quarter, and assets under management in that division totaled $2.2 billion at Sept. 30, compared with $2.3 billion at year-end 2014. The bank said that recent stock market volatility hampered growth in that area.

Cambridge Bancorp recorded $1.2 billion in total loans outstanding on Sept. 30, compared with $1.1 billion at year-end 2014. In its earnings release, the bank attributed growth in its loan portfolio to increases in commercial mortgages ($62.4 million, or 14.1 percent) and residential mortgages ($43.9 million, or 8.7 percent). Additionally, its home equity portfolio increased by $6.2 million, or 10.9 percent, since year-end 2014.

Nonperforming loans made up 0.10 percent of total loans at the end of the third quarter, compared with 0.15 percent at year-end 2014. The bank’s allowance for loan losses totaled $15.3 million, or 1.28 percent of total loans outstanding at Sept. 30, compared with $14.3 million, or 1.32 percent of total loans, at year-end 2014. The increase in provision for loan losses was in response to growth in the loan portfolio, the bank said.

Total deposits increased $108.9 million, or 7.9 percent, over the nine-month period ended Sept. 30, to $1.5 billion. Total assets increased about 8.2 percent to $1.7 billion from $1.6 billion in the year-ago period.