Four fire engines and around 20 firefighters were called to a flat fire on Cromwell Road in South Kensington.
Fire crews wearing breathing apparatus led a woman to safety and another woman was rescued from a second floor flat roof via an aerial ladder. They were both taken to hospital by London Ambulance Service crews.
Half of a ground floor flat was damaged by fire.
The fire is believed to have been caused by a tealight igniting combustible materials.
A London Fire Brigade spokesperson said: "Candles are one of the most common causes of fire.
"It’s really important that you never leave a candle unattended and keep them away from curtains and anything else that can easily catch fire. They should always be kept in a sturdy fire-resistant candleholder.
"You could consider swapping your traditional candles for safer, LED flameless ones.”
The Brigade was called at 0240 and the fire was under control by 0415. Firefighters from Kensington, Chelsea, Fulham and Hammersmith fire stations attended the scene.
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