ISS has retained its contract to provide lunches at 50 primary schools in the London Borough of Redbridge for a further six years, in a deal worth £36m.
The caterers have been working with Redbridge Council to develop a high-quality lunch service for schools in the borough since 2009.
The new agreement, which is worth £6m per year, will start on 1 August 2016 and will run until 31 July 2022.
Uptake for school meals has increased from 36% to 69% over the past seven years since ISS has been working with the council.
The firm said the partnership has evolved the schools meals service into one which is healthy, sustainable, popular and affordable.
ISS currently provides more than three million schools meals in Redbridge every year, with numbers continuing to rise.
The service has been accredited with the Soil Association's Food for Life Silver Catering Mark, which means food is freshly prepared from scratch each day using a selection of sustainable and locally sourced ingredients.
ISS has also introduced a number of initiatives including a gardening grants programme; Food Education Event Days (FEEDs); cooking clubs; the introduction of an online payments system and special lunch theme day celebrations.
The company has also invested in a 10-strong team, including a food ambassador to help pupils, parents and teachers learn where food comes from and how to cook it.
Councillor Elaine Norman, cabinet member for children and young people, said: "Primary school meals have cost £2 since 2012 and when we renewed this contract we were determined to not only ensure the best quality but also the best value for money.
"We want to make sure that families of different incomes have the opportunity to afford a quality school meal and we are very pleased to announce this price freeze."
Mark Davies, managing director, ISS Education, added: "We are committed to continually improving and evolving the service into the future, with the vision of creating excellent mealtime experiences for the children in the borough, as well as providing delicious food.
"Our local team is ambitious and has big plans for the new contract, which will be introduced for the new term in September. It's a very exciting time for school lunches in Redbridge and we thank the schools and the borough for choosing us as their school lunch providers."
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