After his military service ended in 1927, McElroy followed his brother, Thomas, to Houston, where he was a hospital orderly. During World War II he was the head janitor at Ellington Field. He also participated in bond drives as a speaker and poster model, for which Henry Morganthau, Jr., United States Secretary of the Treasury, cited him on January 11, 1945. McElroy was reportedly the first African American whose picture appeared as an advertisement for United States War Bonds. After the war, he worked at local recruiting stations until retiring permanently. HemisFair ’68 in San Antonio honored him in the Texas Pavilion by displaying a life-size portrait of him, beneath which was a recounting of his military record.
In December of 1968 he and his oldest son rescued two children from a burning house near his Houston home. The Texas Senate commended the McElroys for their bravery. McElroy married Philamena Woodley in 1918, and they had four sons and two daughters. He died on December 29, 1971. A detachment from For Sam Houston buried him in Paradise Cemetery, Houston, with full military honors.