Lowell-based Enterprise Bancorp, the parent company of Enterprise Bank, experienced a 15 percent year-over-year growth in net income for the third quarter of this year.

The company’s net income for the three months ended Sept. 30 totaled $3.5 million, up $470,000 from the same period last year. Total assets increased $166.8 million, or 10 percent, since the close of last year, totaling $1.83 billion on Sept. 30.

In a statement, CEO Jack Clancy attributed the quarterly earnings to organic growth and market expansion.

"On an annualized basis, total assets, loans and deposits, excluding brokered deposits, have grown 13 percent, 11 percent and 12 percent, respectively, in 2013. We remain focused on organic growth with investments in technology, our communities and, most importantly, our family of Enterprise employees as we look to continue to strengthen our franchise in Massachusetts and Southern New Hampshire," he said in a statement.

Quarterly net interest income increased 6 percent, or $985,000, to $16.6 million. In the statement accompanying its earnings release, the bank attributed that increase primarily to revenue generated by loan growth, particularly commercial real estate loans.

Total loans amounted to $1.47 billion at the end of the third quarter, an increase of $113 million, or 8 percent, for the nine months ended Sept. 30. For the comparable period last year, loans increased $52.9 million. 

Net interest margin was 4.02 percent for the third quarter, compared with 4.2 percent last year. Year-to-date margins were 4.09 percent and 4.29 percent for the nine months ended Sept. 30, 2013 and 2012, respectively. The company attributed the downward trend in net interest margin to the yield on interest-earning assets declining faster than the cost of funding.

The provision for loan losses amounted to $583,000 for the third quarter, compared with $800,000 last year. For the nine months ended September 30, 2013 and 2012, the provision for loan losses amounted to $1.9 million and $2.2 million, respectively. Total non-performing assets as a percentage of total assets were 1.09 percent at Sept. 30, compared with 1.50 percent last year.

For the nine months ended Sept. 30, the company recorded net charge-offs of $155,000 compared with $1.4 million for the same period last year. The allowance for loan losses to total loans ratio was 1.77 percent at Sept. 30, 2013, 1.78 percent at Dec. 31, 2012 and 1.84 percent at Sept. 30, 2012.