See also: Armstrong Mills, Ontario. Armstrongs Mills is an unincorporated community in Washington Township, Belmont County, in the U.S. state of Ohio.
Armstrong's Mills was originally called Captina Creek, and under the latter name was platted in 1816.[1] A post office called Armstrong's Mills was established in 1840, and remained in operation until 1986.[2] The namesake Armstrong's Mills was a gristmill built by Thomas Armstrong in 1828.[3]