Three fire engines and 14 firefighters and officers were called to a motorbike alight in Parchmore Road, Thornton Heath.
One motorbike was destroyed by fire. The fire also damaged small parts of a ground floor flat, a first floor flat and a second floor flat.
The occupant of the ground floor flat was alerted to the fire by a smoke alarm sounding.
A London Fire Brigade Spokesperson said: “It’s incidents like these that show how important it is to have working smoke alarms that you check regularly in your home. This will give the earliest warning if there is a fire in your home.”
Three people were treated at the scene by London Ambulance Service for smoke inhalation.
The Brigade was called at 0443 and the fire was under control at 0529. Fire crews from Norbury and West Norwood fire stations attended the scene.
The cause of the fire is under investigation.