The 14-year-old, named as Jayden, was last seen at 10.15am on Sunday (February 18), according to Sussex Police.
A statement on social media read: “We are looking for missing 14-year-old Jayden from Haywards Heath.
“He is skinny with messy hair and was last seen wearing a black coat with a fur hood, black Nike tech trousers and black Nike Air Force trainers.
“He has links to East Grinstead. If you see Jayden, please call 999 quoting serial 354 of 18/02.”