American Savings Bank’s earnings jumped nearly 25 percent in the first quarter amid strong growth in its investments and deposits.

The state’s third-largest bank said Friday that its net income rose to $15.8 million from $12.7 million in the year-earlier quarter.

“We are off to a strong start in 2017 as we continue to deliver for our customers and shareholders,” Rich Wacker, president and CEO of American Savings, said in a statement. “Our first-quarter results demonstrate strong core deposit growth, higher net interest income and margins, improved operating efficiency, and better asset quality metrics.”

American Savings’ investment portfolio jumped nearly 36 percent to $1.22 billion from $906 million due to the strong deposit growth. The investments were primarily in mortgage-related agency securities, such as Ginnie Maes. Deposits jumped 10.4 percent during the quarter to $5.68 billion.

“The biggest chunk of our earnings came from growth in net interest income (up 8.8 percent) because of a combination of really strong deposit growth and being able to deploy that into both loan growth and our investment portfolio,” Wacker said in a phone interview. “The deposit growth is the fuel and we were able to deploy it into both of those categories, with the investments having the biggest impact. We also benefited in the quarter from the bump in interest rates since the beginning of the year, particularly in that investment portfolio.”

Loans rose 1.8 percent year over year to $4.73 billion with the commercial sector leading the way, followed by the consumer and residential categories. But loans slipped 0.3 percent from the fourth quarter.

“Total loans declined slightly (from the fourth quarter), reflecting the completion and payoff of a large commercial real estate construction project and the resolution and payoff of a prior nonperforming commercial loan,” Wacker said.

American Savings, which began construction on March 6 of a new $100 million headquarters in Chinatown, is hoping to move in to the building in the fourth quarter of 2018, Wacker said.

“So far they’re doing the foundation,” Wacker said. “There are over 400 pilings that will be placed for the foundation before we can start coming out of the ground. We are more than two-thirds of the way through it.”

The headquarters, which is across the street from Aala Park, will consolidate five separate offices on Oahu into one building where about half of the company’s 1,200 employees will work.

Construction stalled after iwi kupuna — ancestral human remains — were discovered on the property last year during an archaeological survey. Officials worked closely with lineal descendants and the Oahu Burial Council on a burial treatment plan.

The headquarters will have 11 floors, with six set aside for offices totaling 150,000 square feet. The remaining five floors will be for parking.

“We’re thrilled about it because we were so close to starting last year (before the iwi kupuna were found),” said Wacker, whose bank purchased the land in November 2014. “We’re thrilled to be actually moving dirt and to be ready to come up out of the ground.”

Wacker also said the bank plans to reopen a branch in the Kalihi neighborhood where it sold its service center last year, and is in the middle of building a new branch in Kahului and relocating a branch in Kapolei. The branches are due to open in late 2017 or early 2018, he said.

Hawaiian Electric Industries Inc., which owns the bank as well as the state’s largest utility, will report overall financial results next Friday. HEI’s stock fell 34 cents, or 1 percent, on Friday to close at $33.52. The bank’s earnings were announced after the stock market closed.