Four fire engines and around 25 firefighters responded to a fire on Hanbury Street in Whitechapel.
A first floor flat, in a block of two floors, was extensively damaged by the fire. There were no reports of any injuries.
The Brigade received the first of 16 calls about the fire at 1634, and crews had the incident under control by 1725. Firefighters from Whitechapel and Shoreditch Fire Station attended the scene.
The cause of the fire is under investigation by the Brigade and Metropolitan Police Service.