Firefighters were called to a blaze on the third floor of a block of flats.
A crew from Littlehampton station was sent to South Terrace in the town shortly before 11pm on Tuesday night (March 25).
Eight firefighters equipped with breathing masks entered the property with hose reels to put out the blaze.
Other crew members used an aerial ladder platform to inspect the property from the outside.
Nobody was injured.
A fire service investigation is looking into how the blaze started.