The A1133 follows the River Trent downstream from Newark-on-Trent, forming part of the town's link with Gainsborough.
The road starts at a roundabout on the A46 Fosse Way to the northeast of Newark. It heads north, passing to the east of Winthorpe, which it went through before being severed by the present route of the A1. The Newark to Lincoln railway line is crossed at a level crossing before the road runs through Collingham. The next village is Besthorpe, after which the road becomes the Nottinghamshire/Lincolnshire county boundary for a few hundred yards.
The road continues north through the flat land of the Trent Valley, still in Nottinghamshire. However, there are no more villages until the county boundary is crossed properly and we reach Newton-on-Trent (which is actually over half a mile from the river). The A57 is crossed at a staggered crossroads and we pass to the east of the village before zigzagging through Laughterton. The road ends about a mile further on just to the south of Torksey Lock on the A156.
Originally numbered B1186 the A1133 gained its current number around 1960.