Four fire engines and around 25 firefighters were called to a fire at a hotel on Wellesley Road in Croydon.
Part of a linen room on the third floor of the building was damaged by fire. Around 50 people left the building before the Brigade arrived. There were no reports of any injuries.
A London Fire Brigade spokesperson said: “On arrival crews found light smoke logging in the third floor bedroom corridor and discovered a small fire in the linen cupboard.
“Thankfully, smoke alarms fitted inside the property were able to give the earliest possible warning to the fire and alerted staff, providing time to escape.”
The Brigade was called at 1220 and the fire was under control by 1311. Fire crews from Wallington, West Norwood, Beckenham and Addington fire stations attended the scene.
The cause of the fire is under investigation by the Brigade and the Metropolitan Police Service.