Four fire engines and around 25 firefighters were called to a fire at a block of flats in Peckford Place in Brixton.
Part of a maisonette on the ground and first floors of the building was damaged by fire.
The Brigade was called at 1255 and the fire was under control at 1339. Fire crews from Brixton, Clapham and Lambeth fire stations attended the scene.
The cause of the fire is under investigation.