Navy Federal Credit Union opened a “technology concept branch” at Potomac Yard in Alexandria earlier this month. (Jeffrey MacMillan/Jeffrey MacMillan)

As the world’s largest credit union, Navy Federal has nearly 250 branches and, as of last month, 5 million members.

Now it’s about to get even bigger.

To keep up with growing membership, which has risen 25 percent since 2012, the credit union is opening 60 new branches across the country by 2016.

In the Washington area, the Vienna-based credit union plans to add about a dozen locations in the next two years.

Growth “is faster than it has been in the past,” said Steve Romano, executive vice president of branch operations for Navy Federal. “Our members like to use our branches, and they’re asking for more.”

In addition to an upcoming location in Frederick, Navy Federal also has plans to open branches in Crofton, Waldorf, Bowie and Gaithersburg in 2015.

“Branches are focused where we have the most concentration of members and where we’re seeing growth,” Romano said, adding that demand is up in the Washington region, as well as Tidewater, Va.; Jacksonville, Fla.; and San Diego.

The credit union’s expansion comes at a time when most financial institutions are shuttering physical locations to save costs. Plus, they say, customers are increasingly likely to deposit a check via smartphone or ATM without stepping foot into a bank.

But at Navy Federal, Romano says demand for branches — which sometimes offer notary and power of attorney services at military bases — has been on the rise.

This month, the credit union opened its first “technology concept branch” in Alexandria’s Potomac Yard, marking its 32nd area location.

Instead of traditional teller lines, the 3,300-square-foot branch offers a more interactive experience, Romano said. There are iPads and smartphones on hand to show members how to use the credit union’s mobile apps to make deposits, transfer money and check balances. A kids’ area includes electronic games about financial literacy.

“This is more personal than your typical branch,” Romano said. “There is a very comfortable wooden desk where members can sit down with an iPad or an Android if they want to.”

The credit union’s newest members are typically between the ages of 18 and 34, Romano said, adding that they are interested in learning how to use new banking technology.

“When you join, we want to show you all of the different capabilities we have,” Romano said. “It’s sort of like when you buy a car and the [salesman] drives it around the neighborhood and shows you all the features.”

As of March 2014, Navy Federal had $58.16 billion in asserts, a 7 percent increase from the year before. Membership is open to U.S. military personnel and their families, as well as Defense Department employees.