A further £75m is coming from the National Gallery Trust, National Gallery’s chairman of trustees, John Booth, plus other donors who wish to remain anonymous.
This funding will also support the gallery’s “move to extend its historic collection and marks the beginning of an exciting new collaboration with Tate and other museums in the United Kingdom and around the world”, the institution said.
Founded by Parliament in 1824, the gallery, which has free entry, houses the nation’s collection of paintings in the Western European tradition from the late 13th to the early 20th century.
The collection includes works by Cezanne, Degas, Da Vinci, Monet, Raphael, Rembrandt, Renoir, Rubens, Titian, Turner, Van Dyck, Van Gogh and Velázquez.
Director of the National Gallery, Sir Gabriele Finaldi, has said he is “hugely excited by these developments and are immensely grateful to our donors for their support – on an unprecedented scale – as the National Gallery steps into its third century”.
He added: “With the bicentenary celebrations now completed, the National Gallery looks to the future.
“We want to be the place where the UK public and visitors from across the globe can enjoy the finest painting collection in the world from medieval times to our own, in a superb architectural setting.”