BaxterStorey has filed away a £5.2m contract to provide catering services at the National Archives in Kew, south east London.
The new five-year deal starts in July this year and can be extended for up to two more years.
BaxterStorey has dislodged incumbent Genuine Dining Co in order to win the deal, although it is not clear if Genuine Dining Co was among the four firms who bid for the new contract.
The National Archive holds over 11 million historical and government records, and houses around 550 staff, welcoming in 80,000 visitors per year.
The older of the two buildings that make up the site, built in 1977, contains a kitchen, main restaurant, coffee bar, and staff canteen, all on the ground floor.
The National Archives is embarking on plans to redevelop its public space and has tendered its catering contract with a view to the catering playing a part in the transformation.
Within the next six years, it hopes to increase the number of visitors per year to 180,000.
Genuine Dining Co held the contract since 2007. Its total net contract turnover for the financial year 1 April 2015 to 31 March 2016 was around £559,000, according to tender documents.
Commenting on the winning the contract, a spokesperson for BaxterStorey said: "We are delighted to be working with National Archives in Kew and look forward to surprising and delighting customers with delicious seasonal menus and great service."
No-one from Genuine Dining Co was available to comment as this story was posted online.
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