Business caterer Eurest is now serving more than 20,000 Centrica employees across the country with the expansion of its contract to include a further two British Gas facilities.
Eurest's responsibilities, worth a total turnover of £21 million over five years, now include British Gas sites in Manchester and Solihull.
Sister company, Selecta, has also been appointed to handle the vending operations for the sites.
Eurest, which has been involved in on-site catering for most British Gas bases for over five years, will now be servicing a total of 18 Centrica outlets across the UK, ranging from call centres to head offices.
Karen Juniper, operations director at Eurest, said: "We have a strong track record with Centrica across the UK, but every site is unique with its own individual needs, so we are working closely with staff at Manchester and Solihull to make sure we are delivering a service that meets their specific requirements.
"It is early days, but we are already considering upgrading the facilities and have been experimenting with menu changes to gauge what is well received by the employees."
Brian Amos, facilities manager of Centrica, added: " Centrica has built up a strong relationship with Eurest over the years. We are delighted to bring them on board to handle these additional sites."
Eurest is a member of the Compass Group, the world's leading foodservice company, with annual revenues of £12 billion and 400,000 employees in over 90 countries.