Hillandale is an unincorporated area and census-designated place located in Montgomery and Prince George's counties, Maryland, United States. As of the 2020 census, it had a population of 5,774. Hillandale is contained between the Prince George's / Montgomery County line to the east, the Anacostia River to the west, McCeney Avenue to the north, and D.C.'s Capital Beltway to the south. It borders the communities of Adelphi, Avenel, White Oak and Beltsville.
Geography
Hillandale is part of the very large postal designation of Silver Spring.
According to the United States Census Bureau, the place has a total area of , all land.
In Montgomery County, Hillandale is bordered by the Silver Spring CDP to the south (across the Capital Beltway), the Four Corners CDP to the west (across the Northwest Branch Anacostia River), and the White Oak CDP to the north. In Prince George's County, Hillandale is bordered by the Beltsville CDP to the east (across the Paint Branch) and the Adelphi CDP to the south (across the Capital Beltway).