Craig Griffin was last seen in the area of Colombus Street at lunchtime on Wednesday.
The 54-year-old is believed to be wearing a ‘MERC’ jacket with grey elbow patches and blue jeans. He is 5 ft 8 ins tall and may be wearing glasses.
The States police have been liaising with his family and friends, checking locations he is known to visit and analysing CCTV footage.
Anyone with information is being asked to phone the States police on 612612.