Six fire engines and around 40 firefighters were called to a fire at a house on Chamberlayne Road, Kensal Rise.
Most of the first floor and part of the roof was damaged by fire.
The Brigade was called at 2249 and the fire was under control at 0103. Fire crews from West Hampstead, North Kensington, Willesden and Paddington fire stations attended the scene.
The cause of the fire is under investigation.