Ten fire engines and around 70 firefighters were called to a fire at flats above a shop on Green Lanes in Southgate.
Most of the first and second floor of the flats were destroyed by fire.
Six people self evacuated before the Brigade arrived. No injuries are reported.
The Brigade was called at 0736 and was under control by 1021. Fire crews from Southgate, Hornsey, Tottenham, Edmonton, Finchley fire stations were at the scene.
The cause of the fire is under investigation but it's believed to be accidental.