Potomac (/pəˈtoʊmək/ ⓘ) is an unincorporated community and census-designated place in Montgomery County, Maryland, United States.

Throughout the 18th century, what became known as "Offutts Crossroads" was a small, rural community which served planters and travelers.

An Irishman and veteran of the Civil War, McDonald settled in Potomac around that time.

Thomas Perry, an operator of a nearby general store, built a house on the corner of Falls and River Roads in 1902.

The Perry Store has been restored and still stands as part of a bank, although the building was moved 21 feet in 1986 to allow for a project to widen the intersection of Falls and River Roads.

Potomac's geographical focal point is Potomac Village, a small cluster of shops and businesses at the intersection of Maryland State Highway 189 (Falls Road) and Maryland State Highway 190 (River Road) northwest of Washington, D.C.

The climate is characterized by hot, humid summers and generally cool to cold winters with light snow.

Fourteen percent of all households were made up of individuals, and 5.9% were persons living alone who were 65 or older.