Jordan Thomas Both, aged 31 and from Skelton, was last seen on November 3 and last spoke to his family on Tuesday.
Extensive investigations are underway to find him, North Yorkshire Police has said, as officers are concerned for his welfare.
He is white, with short dark brown hair, of slim build, and 5ft 8ins tall. He speaks with a local accent.
Anyone who sees Jordan, or knows where he is, is asked to contact North Yorkshire Police on 101, quoting reference number 12180209880.