Interserve has been named one of six providers on the Ministry of Justice's £4 billion Prison Operator Services Framework agreement.
The business currently runs five community rehabilitation companies (CRCs) that provide probation services to 25 per cent of low and medium-risk offenders across the country.
Interserve also runs an employment centre at HMP Berwyn to train prisoners for employment post-release.
The framework is part of the government's programme to deliver up to 10,000 new, modern, and decent prison places.
The framework enables Interserve to enter into mini-competitions for the provision of operational custodial services and facilities management services at the new prisons at Wellingborough and Glen Parva and potentially existing privately-operated prisons that are approaching the end of their contracts.
Ian Mulholland, managing director, public sector, said: "We have gained considerable experience delivering services in prisons because of the 'Through the Gate' service we deliver as part of our CRC contracts.
"We believe our innovative approach to delivering rehabilitative services marks us out from our competitors and makes us the ideal choice for further expansion in this market."