Georgia Derrico, chief executive of Southern National Bancorp, the parent company of Sonabank, and husband Rod Porter, Sonabank president, at their administrative offices in Georgetown. (Evy Mages/FOR THE WASHINGTON POST)

Nearly a year after acquiring HarVest Bank of Maryland, McLean-based Southern National Bancorp of Virginia is settling into the state and looking toward a possible expansion in the District.

Married couple Georgia Derrico and Roderick Porter started Southern National, the holding company for Sonabank, in 2005 with about $35 million in capital. Since then, it has grown to include 20 branches in Virginia and Maryland, and $722.1 million in assets.

“We’d love to be in Washington, if we get the right location,” said Derrico, the bank’s chairman and chief executive.

Sonabank has been undergoing an aggressive expansion since its founding eight years ago. In 2006, it acquired 1st Service Bank in McLean, and three years later, Reston-based Great Atlantic Bank.

“We would like to acquire additional small banks and branches,” Derrico said, adding that she would like the bank to have at least $1 billion to $1.5 billion in assets. “In this environment, you really need to be larger because of all the regulations.”

The bank’s fourth-quarter profits more than quadrupled to $1.3 million from $225,000 a year earlier, following the purchase of HarVest Bank.

Derrico and Porter said they shy away from mortgages and consumer loans, but have made their mark lending to small businesses in the area, ranging from government contractors to veterinarian clinics.

“Everybody pretty much offers the same things — electronic banking and on and on,” said Porter, who serves as the bank’s president. “Where we offer the additional wrinkles is with small-business lending.”

Last year, the bank lent $8.14 million to small businesses, including money for Uptown Alley, Steven Uphoff’s $20 million bowling alley and entertainment complex in Midlothian.

“Our customers know we’re behind them,” Porter said. “They know we don’t want to foreclose on them. We just want them to be successful.”

This is the second bank the couple has started from scratch, having sold the first one — Herndon-based Southern Financial Bancorp — in 2004.

It was a slower slog then, Derrico said. She started the bank in 1986 after a stint as a senior vice president at New York-based Chemical Bank (now JPMorgan Chase), where she met Porter.

“I was at Chemical Bank and I realized this is too bureaucratic,” Derrico said. “I wanted to do something different. Rod said, ‘You don’t know how to do anything but banking. Why don’t you start a bank?’ ”

Derrico wasn’t sure where to begin. She called up a friend in Florida who had recently founded a bank and asked for pointers.

Eventually she raised $4 million from friends and family. That was enough, she decided, to get started.

“We grew very, very slowly,” Derrico said from the bank’s office in Georgetown. “It was hard. I don’t know that I could do it again.”

In 1998, Porter joined the bank full-time. In the next five years, the company would acquire four banks, boosting its assets from $200 million to $1.3 billion in assets.

Derrico and Porter are hoping for a quicker expansion this time around.

“We’ve surrounded Washington, but we’re not in Washington yet,” Porter said. “That’s the next step.”