Caterer Wilson Vale has won a £400,000 contract with Fulneck School in Pudsey, West Yorkshire.
The contract began last month, and sees Wilson Vale provide breakfast, morning break, lunch and borders' tea seven days a week to 500 pupils and staff.
Formerly operated in-house, the £400,000 contract is initially for one year. It takes Wilson Vale's portfolio of independent schools to 25.
Fulneck principle Deborah Newman said: "At Fulneck we are acutely aware of the need for our pupils to be offered a nutritious, healthy diet, and of the impact this has on the learning and developmental process. Having reviewed our catering service, we made a decision to appoint Wilson Vale as our catering provider."
Andrew Wilson, co-founder and managing director of Wilson Vale, added: "Our fresh food ethos and strong operational focus continues to attract like-minded clients who value quality and consistency. We feel very honoured to be working with a school that places so much emphasis on the wellbeing and support of its pupils and staff."