DYFED-Powys Police is concerned for missing 17-year-old Dafydd Harley, from the Llangyndeyrn area.
Dafydd was last seen at approx 2pm on Wednesday, 23 January 2019, at his home address in Llangyndeyrn.
It is believed he could be in the Carmarthen or Llanelli area. He is described as white, is of medium build, has a beard, and mousy hair. He is likely to be wearing a red hoodie, and black combat trousers, black or navy trainers and a fake leather jacket with a hood.
Anyone with any information about his whereabouts, or anyone who thinks they may have seen him, please contact PC 425 Katie Roberts at Burry Port police station by calling 101.
If you are deaf, hard of hearing or speech impaired, please text 07811311908.