The station buildings at Trawsfynydd were on the Down (northbound) side and provided a ticket office, waiting room, a lavatory and a urinal as well as rooms for staff use and a substantial signalbox on the platform. The Up platform had a waiting room.
The station buildings at Trawsfynydd were situated on the Down (northbound) side of the railway line and included amenities such as a ticket office, waiting room, restroom facilities, a urinal, staff rooms, and a signal box on the platform. The Up platform had its own waiting room.