Firefighters were called to a fire at a flat on Brunswick Square in Bloomsbury.
Part of a three-roomed flat on the second floor of a residential block was damaged by fire. One man left the building before the Brigade arrived and was taken to hospital by London Ambulance Service crews.
The fire is believed to have been accidental and caused by a toaster.
A London Fire Brigade spokesperson said: “Avoid keeping items such as toasters under cupboards or in contact with combustible items such as tea towels or kitchen roll to prevent heat build-up.
“It’s also important to make sure you keep toasters clean to help prevent fires.
“The online tool will ask you a series of questions that will help us work out the level of risk in your home, or the home of someone you care for. It only takes a few minutes to get tailored advice to keep yourself and loved ones safe from fire.”
The Brigade was called at 2227 and the fire was under control by 2331. Five fire engines and around 35 firefighters from Euston, Soho, Islington, Shoreditch and Kentish Town fire stations attended the scene.