| State: | OH |
| Type: | US |
| Route: | 20A |
| Map Custom: | yes |
| Length Mi: | 52.448 |
| Length Ref: | [1] |
| Direction A: | West |
| Terminus A: | west of Pioneer |
| Junction: |
|
| Direction B: | East |
| Terminus B: | in Maumee |
| Counties: | Williams, Fulton, Lucas |
| Formed: | 1935[2] |
| Previous Type: | OH 1920 |
| Previous Route: | 20 |
| Previous Dab: | 1923-1927 |
| Next Type: | US |
| Next Route: | 21 |
U.S. Route 20A (US 20A) is a 52.4adj=midNaNadj=mid east–west alternate route of US 20 located in northwest Ohio. The western terminus of the route is at US 20 southwest of Pioneer, and the eastern terminus is at US 20 in Maumee, southwest of Toledo.
The route runs parallel to the Ohio Turnpike (Interstate 80/Interstate 90 [I-80/I-90]) for much of its length, and intersects the turnpike at exit 13 northeast of Montpelier in Holiday City. US 20 and US 20A are never more than 5miles apart for the entire 50miles stretch through the Ohio farm country, as the mainline of US 20 takes the more northerly route.
The current US 20A was designated U.S. Route 20S (US 20S) in 1932, which replaced State Route 271 (SR 271) which had run from US 20 south to Montpelier, truncated SR 107, joined SR 2, and followed a road formerly not on the state highway system through most of Lucas County. It became US 20A in 1935. US 20A was moved to its current location along SR 15 from SR 576 and SR 107 in 1964. (SR 107 then reclaimed some of the miles that had been taken from it in 1932.)[2] In the 1950s, part of the road east of Swanton was abandoned to make way for Toledo Express Airport.