Lexington Catering has been named a three-star sustainability champion by the Sustainable Restaurant Association (SRA).
The boutique catering brand, which was last week bought by Elior, was recognised for its approach to sourcing local and seasonal food and sustainable fish.
Commenting on the achievement, managing director Julia Edmonds said the accreditation demonstrated the company's commitment to minimising and continually improving its impact on the environment.
She added: "From day one our philosophy on food has been to develop great tasting, simple, seasonal menus using the best of British produce. By following this guiding principle we source the freshest of ingredients from local suppliers, which in turn reduces our carbon footprint.
"It's thanks to our fabulous team, who work hard to stick to our principles and remain focused on reducing our impact on the environment, balancing quality and ethics with profit, that we are able to maintain this across all of our client sites."
Mark Linehan, managing director of the SRA, also commented: "Serving thousands of meals every day, Lexington has a responsibility to serve its customers well sourced, healthy food. It's clear that the company is committed to doing just that, as well as putting people, both employees and clients, at the heart of the business. Employees are treated in a fair and supportive way.
"Lexington has achieved so much in terms of growth and profit but continues to operate in a sustainable way, which should inspire other businesses to do the same."