The charity will pledge a further £100,000 per annum to Bletchley Park over the next three years, on condition that the funding is matched by outside partners.
The endorsement has given a much needed boost to fundraising efforts, according to Simon Greenish, director of the Bletchley Park Trust.
"We are infinitely more optimistic that these buildings will be restored for future generations, and we are actively inviting other organisations and individuals to step forward to help drive this crucial regeneration initiative, " he said.
Bletchley Park was home to World War II code breaking efforts and was where the Enigma code was finally cracked.
Huts 1, 3 and 6, where Enigma code breaking efforts were concentrated, are in dire need of restoration, while Hut 11, wartime home to the Turing-Welchman Bombe machines, is also in a critical state of repair.
Last week, English Heritage gave Bletchley Park a £330,000 grant to cover urgent repair works to the roof of the Grade II listed Mansion.
Microsoft comes up with a new way to foist its unloved and little used Edge web browser on people
Facebook suspends Cambridge Analytica following weekend claims that it illegally harvested information from 50 million users
Insider claims Cambridge Analytica used academic app to filch Facebook data of 50 million users
Is the Samsung Galaxy S9+ worth its high price?