Four fire engines and around 25 firefighters tackled a fire in a semi detached house in Whitehorse Road, Croydon.
Part of the ground floor was damaged by fire. One woman left the house before crews arrived and was taken to hospital by London Ambulance Service.
The Brigade was called at 0852 and the fire was under control by 0959. Fire crews from Croydon and Norbury Fire Stations attended the incident.
The cause of the fire is under investigation.