Cambridge Trust Co. reported $4 billion in assets but saw an earnings loss in the second quarter after its merger with Wellesley Bank affected expenses and the provision for loan losses.

The bank had a net loss of $1.7 million in the second quarter, down 140.2 percent compared to net income of $4.27 million in the second quarter of 2019. The diluted loss per share was $0.29 in the second quarter compared to diluted earnings per share of $0.90 for the same period last year.

Net income for the first six months of 2020 was $5.5 million, a 47.3 percent decrease from the first six months of 2019, when net income was $10.47 million.

The merger with Wellesley Bank was finalized June 1, and paid a total consideration of $88.8 million, according to its second quarter earnings statement, with more than 1.5 million shares of Cambridge Bancorp common stock issued to Wellesley shareholders.

The combined bank now has $4 billion in total assets as of June 30, increasing 40.9 percent since Dec. 31.

The merger added $870 million to Cambridge Trust’s loan portfolio, bringing the total on June 30 of $3.3 billion. The bank also had organic loan growth this year of $79.1 million, not including Paycheck Protection Program loans. The bank’s 892 PPP loans through June 30 totaled $189.3 million.

Deposits increased by $760.9 million as a result of the merger and grew organically by another $191.9 million. Total deposits now stand at $3.3 billion.

The merger had a significant impact on Cambridge Trust’s provision for credit losses. The total provision expense for the second quarter was $14.4 million, with $8.6 million attributed to the merger’s effect from the current expected credit loss (CECL) accounting methodology.

The bank also added a $5.7 million provision for credit losses due to anticipated losses from the pandemic and changes in loan balances.

Non-interest expenses increased by $4.1 million, or 18.9 percent, since the second quarter of 2019 to $25.6 million. This included $2.1 million more for salaries and employee benefits, an 18.2 percent increase driven in part by mergers with both Wellesley Bank and Optima Bank & Trust, which was completed in 2019.

Costs associated with additional branches and technology investments also contributed to rising expenses.

“Throughout this period of uncertainty, we were able to deliver for our clients not only in terms of support through the PPP program, but also for our communities in terms of outreach. I want to specifically thank my colleagues for all of their hard work and welcome our new colleagues from our merger with Wellesley,” Denis K. Sheahan, Cambridge Trust’s chairman and CEO, said in a statement. “Although the quarter’s results include the one-time impact of the merger on our allowance for credit losses as required by CECL and a continued increase in provisioning levels associated with the COVID-19 pandemic, we delivered solid operating results with continued strength in asset quality.”