White Plains is an unincorporated community in Charles County, Maryland, in the United States, just south of Waldorf. It is at latitude 38°35'25" N, longitude 76°56'26" W. The United States Postal Service has assigned White Plains the ZIP Code 20695. The commercial portion of White Plains lies along U.S. Route 301. The area is experiencing population sprawl from the adjacent unincorporated communities of Waldorf and St. Charles and features new office parks and a scenic new rail trail.