Four fire engines and 21 firefighters and officers were called to a fire at a launderette in Waterloo Road, Southwark.
Neighbours called 999 after seeing smoke coming out of back window of the launderette.
The fire destroyed a tumble dryer and a small part of the shop also sustained damage.
The Brigade was called at 2115 and the fire was under control at 2151. Fire crews from Lambeth, Old Kent Road, Dockhead, and Dowgate fire stations attended the scene.