Clink Events, the catering service run by the Clink Charity has been named as a preferred caterer for the Guildhall London.
The Clink joins 15 other eligible caterers for the venue.
A three-year contract will begin in January 2018 where the Clink will cater for events at the hall such as drinks receptions and canapés, to food stations and fine dining.
Chris Moore, chief executive of the Clink Charity, said: "We are thrilled that Clink Events has been appointed by Guildhall as a eligible caterer. To be recognised by a renowned historical venue, such as Guildhall, and to be listed alongside other well-established caterers is an outstanding achievement for the Clink Events team.
"By working alongside like-minded charities such as Centrepoint, the UK's leading young homeless charity, Clink Events is providing second chances to those that want and deserve one, and our partnership with Guildhall will contribute to the growth of the Clink Events service. We look forward to providing a professional service and delicious food to the events at Guildhall."
Guildhall is home to the City of London Corporation and seven event spaces, which can facilitate up to 900 guests.
Noa Burger, head of responsible business at the City of London Corporation, said: "We are very excited about our partnership with the Clink Charity. This linkup will provide a real opportunity for prisoners to learn new skills in the catering business, develop their expertise and support them to resettle into the community.
"We want to encourage and support the capital's charities and responsible businesses, to help them change the lives of hundreds of thousands of Londoners. It's a brilliant way to demonstrate your organisation's values, engage your staff and make a real difference."
The Clink Charity is a rehabilitation initiative that trains up to 160 prisoners a day for 40 hours a week to work towards an NVQ qualification in food preparation, food service and food hygiene.
The Clink Events donates 100% of profits to the charity's training projects.
Clink Charity wins Social Enterprise award >>
The Clink hopes to launch second prison restaurant in Cardiff >>
TV historian Dan Snow joins the Clink Charity as communications ambassador >>
Videos from The Caterer archives