The Tate Modern normally opens at 10:00 and closes at 18:00 every day, and is free to enter.
Karin Hindsbo, director of the Tate Modern, said: “Over the last decade, Tate Modern Lates have become a cornerstone of London’s nightlife, especially among young Londoners who want to make the most of their city’s dynamic cultural scene.”
She said opening until late would make the gallery “even more accessible”.
The mayor of London said the move would help to cement London as the “cultural capital of the world, with the best nightlife anywhere”.