The M181 is a motorway that links the town of Scunthorpe, England, to the M180 motorway. A spur of the M180, the road is virtually straight through its entire 2-mile (3.2 km) length. It was opened in December 1978, at the same time as the section of M180 from junction 3 (A15) to the east side of the River Trent (the bridge was not opened until late 1979).
It begins just outside Scunthorpe, at the junction of the A1077 and A18. There is an out-of-town retail park, known locally as Gallagher Retail Park, which offers a wide variety of food and retail outlets, and Glanford Park, the home of Scunthorpe United Football Club at this junction. At the other end, the road has a junction for the M180 east, while the main carriageway merges with the M180 west. It has no intermediate junctions. It is built to typical British motorway standards, being two lanes in each direction, plus a hard shoulder for its entire length.