Four fire engines and around 25 firefighters were called to a house fire on Ferndale Crescent in Carshalton.
Part of the ground floor of a mid-terraced house was damaged by fire.
Sub Officer Peter Davis, who was at the scene, said: “Crews arrived to find heavy smoke that had travelled through the house and worked quickly to gain access and bring the fire under control.
“One woman left the building before the Brigade arrived and was treated on scene by London Ambulance Service crews.”
The Brigade was called at 1918 and the fire was under control by 2012. Fire crews from Mitcham, Sutton, Wimbledon and Wallington fire stations attended the scene.
The fire is believed to have been accidental and involved an electric griddle.