The weather encouraged hiring in construction and agriculture, Gossert said.
In Washington County, an estimated 64,444 people were employed in March compared with 63,514 workers in February, according to the labor department. The county's labor force grew from 67,434 people to an estimated 68,015 people from February to March.
In Frederick County, Md., the unemployment rate also fell, from 4.5 percent in February to an estimated 3.9 percent in March.
The state's jobless rate fell from 5 percent in February to an estimated 4.6 percent in March.
"This is outstanding news for all of Maryland, particularly Western Maryland and the Eastern Shore," said Gov. Parris Glendening in a prepared statement.
"Coupled with the drop in unemployment, Maryland has experienced record high employment levels each month for more than a year. It is also significant that job growth continues and the unemployment rate has been consistently lower than the national level - all reflecting the ongoing strength of the state's economy," Glendening said.
Nationally, the jobless rate fell from 5.7 percent in February to an estimated 5.5 percent in March.