Firefighters rescued a woman from her burning flat in Hayes , after a neighbour raised the alarm.
Fire crews wearing breathing apparatus entered the property and led the woman to safety.
She was treated at the scene by London Ambulance Service (LAS) crews after they were called at 6.53am.
An LAS spokesperson said: "We sent a paramedic in a car, an ambulance crew and our hazardous area response team to the scene.
"We checked over a woman at the scene and took her to hospital."
The woman was treated for smoke inhalation.
It took the brigade just under half an hour to control the blaze, with firefighters from Heathrow and Hayes attending the scene.
The cause of the fire is under investigation by fire officers and the police.
A Metropolitan Police spokesperson confirmed that no criminal investigation is underway at this stage.