The Brookwood Partnership and its sister business Absolutely Catering have become the first school foodservice firms to be awarded three stars by the Sustainable Restaurant Association (SRA).
The independent caterer was recognised for its proactive and inclusive approach to its corporate social responsibility spearheaded by its Planet Matters programme.
Brookwood, which bought Graysons Education last year before rebranding it as Absolutely Catering in September, achieved a total SRA score of 70%.
This was broken down as follows: healthy eating (100%), community involvement (99%), waste management (90%), society (97%) environment (67%) and sourcing (57%).
Commenting on the achievement, managing partner Kate Martin said that providing more than 60,000 fresh meals each school day was "no mean feat" and that the business continually strives to reduce any negative impact its work has on the environment.
"It is with great pride that we have been awarded this accreditation and in being the first schools' caterer," she said. "I am continually proud of the lengths our teams go to each day in order to help protect the environment and give something back to others."
Mark Linehan, SRA managing director, added: "Enabling schoolchildren to eat healthy, well sourced food sets a standard which we believe will set them up for the rest of their lives, as healthy adults equipped to make responsible decisions about what and where they eat.
"So we applaud the Brookwood Partnership for setting an example for all school caterers and look forward to working with them to build on this very impressive start."
Company initiatives that helped Brookwood achieve the three stars included Wasteless, which helped reduce plate waste by 47%, local sourcing and company-wide charity work.