Deposits at commercial banks in the Washington metropolitan area rose about 10.86 percent in the past 12 months to a record $14.328 billion on March 31, 1981, compared with $12.924 billion recorded a year earlier, according to a Washington Post survey. All three regional areas surveyed showed increases in total net deposits, although nine local banks registered decreases from March 31, 1980.

Following a trend established in the past few years, District banks and their branches posted the largest annual increase, showing a 12.17 percent increase in savings, up from total net deposits of $6.282 billion in March 1980 to just over $7.046 billion this year. District deposits showed an increase of 1.55 percent during the quarter ended March 31, 1981, up more than $107.3 million from the $6.939 billion total compiled Dec. 31, 1980.

Maryland banks and their branches showed more moderate growth, increasing 5.48 percent to more than $3.558 billion a year earlier. Maryland deposits dropped .06 percent, from $3,855 billion on Dec. 31, 1980 to $3.853 billion percent for the quarter ended March 31, 1981.

In Virginia, deposits rose to more than $3.528 billion, up 9.14 percent over last year's figure of $3.232 billion. The quarterly increase, from $3.453 billion, was 2.17 percent.