In 1923 the route at later became SR 25 was signed as SR 6. The SR 6 designation was changed to US 25 on November 11, 1926. Between 1946 and 1948 the roadway was widened to a four-lane divided highway, between Bowling Green and Maumee. With the section south of Bowling Green being widened to a four-lane divided highway between 1951 and 1953. US 25 was decommissioned in 1973 and SR 25 was signed along its northern section. In 1986, SR 25 and US 24 switched routes north of the intersection at Detroit Avenue. Between 1997 and 1999 the road from the second interchange with I–75 and I–280 was widened into a four-lane divided highway.