Diversions were put in place in Ettingshall for drivers in the aftermath of the collision as emergency services attended the scene.
The crash occurred on the junction of Laburnam Road and Dovedale Road at about 6pm on Thursday.
National Express West Midlands tweeted: "81 bus diversion, due to a road traffic collision junction of Laburnam Road and Dovedale Road.
"Diversion: Towards Dudley; Birmingham New Road, Ward Grove, Dovedale Road and towards Wolverhampton: Dovedale Road, Ward Grove, Birmingham New Road.
Witnesses at the scene described how the car which crashed had flipped onto its roof and flattened a telegraph pole.