The M4 Motorway is a key piece of transport infrastructure in Western Sydney. It is an urban expressway of 40kms, connecting Concord with Penrith. Statewide Roads operated and maintained 2 sections of the Motorway, a 2.5km section between Silverwater Road and James Ruse Drive at Auburn, and a 10km section between May's Hill and Prospect as a toll road for a concession period of 18 years.

On 16 February 2010, ownership of the road reverted back to the NSW Government and the toll was removed. However, any unpaid tolls for trips on the M4 up to and including 15 February 2010 remain payable to Statewide Roads.

The operation and maintenance of the M4 is now the responsibility of the NSW Roads and Traffic Authority.

The twin Service Centres at Prospect will continue under Statewide Roads ownership and control until 2017.