The S1 was derived from Rolls-Royce's complete redesign of its standard production car after World War II, the Silver Cloud.

The car was announced at the end of April 1955,[2] and it was noted that the existing Continental model would continue.

It was a more generously sized five- or six-seater saloon, with the body manufactured in pressed steel with stressed skin construction.

Lighter weight fixed-head and drophead coupé bodies were provided to special order (for a premium of about 50%) by H. J. Mulliner & Co., Park Ward, James Young and Freestone & Webb.

A pre-production 2-seater fixed-head coupé on the new chassis was designed and built for the Bentley factory by Pininfarina.