In an effort to get more of Washington's personal banking business, American Security Bank plans to open five more branches in the District of Columbia in the next year.

The expansion drive will give American Security, the District's second largest bank in deposits, 36 banking locations. Riggs National Bank, the biggest in deposits, list 24 branches in its latest annual report.

American Security's first new branch opens this week at 5505 Connecticut Avenue, NW, just south of Chevy Chase Circle.

By the end of 1978, the bank plans to open a branch at the Washington Hospital Center to be followed by ones at 1st and D Streets SE., Wisconsin Avenue and Albermarle Streets NW, and 44th and Jennifer Streets NW.

J. Timothy Holland, American Security's senior vice president for retail banking, said the additional branches are intended to give the bank a greater share of the Washington banking business and to increase the portion of the bank's business that comes from retail accounts.

The new offices will generally follow the prototype of a branch at 4834 MacArthur Blvd. NW, where American Security earlier this year unveiled it's "supermarket" style of banking.

The small MacArthur Boulevard office is "exceeding our deposit targets," Holland said, an indication of the success of the office and the marketing approach built around it.

"In a year when banks and savings and loans have been losing savings deposits, we've picked up a lot," said Holland, declining to specify how much of American Security's business now comes from personal business.

The new Connecticut Avenue office, he said, will introduce another new service - a customer service unit, with a special telephone connecting the customer to an operations center that can answer questions about all accounts, loans or other banking transactions.