Four fire engines and around 25 firefighters were called to a fire at a shop with flats above on High Road in East Finchley.
Part of a third floor flat was damaged by the fire. There were no reports of any injuries.
The Brigade’s 999 Control Officers took nine calls to the blaze.
The Brigade was called at 1433 and the fire was under control by 1557. Fire crews from Hornsey, Kentish Town and Finchley fire stations were at the scene.
The fire is believed to have been accidental and caused by a fault within the mains electricity supply.