Trefasser is a village in Pembrokeshire, Wales.
It is situated within the SA64 postcode district, which is within the Goodwick post town.
SA64 is the only postcode district within the Goodwick post town.
The Goodwick post town is within the Swansea postcode area.
Administrative Ward: Scleddau
Administrative District: Pembrokeshire
Country: Wales
UK Parliament: Preseli Pembrokeshire