After the Mexican–American War ended, Reno served in several locations, including as a mathematics instructor at West Point, as the secretary of a group assigned to "create a system of instruction for heavy artillery, and at the Ordnance Board in Washington, D.C. He was promoted to first lieutenant, in 1853, and sent to conduct a road survey from the Big Sioux River to Mendota, Minnesota. When he returned to Washington, he married Mary Blanes Cross, and the couple had five children, two of whom had notable achievements of their own: Conrad Reno became an attorney and writer of note in Boston, Massachusetts, and Jesse W. Reno graduated from Lehigh University and invented the first working escalator.