This allows customers to buy or bid for First Class upgrades at a reduced cost on selected routes.
These include some of TfW’s most popular journeys between Cardiff and Holyhead, and Cardiff and Manchester – which calls at Newport, Cwmbran, Pontypool and Abergavenny.
Johnathan Jones, head of network growth at TfW, said: “We’re delighted to be working with Seatfrog to offer our customers the chance to experience First Class travel at a great price.”
Iain Griffin, CEO of Seatfrog, commented: “We’re thrilled to be partnering with Transport for Wales to offer passengers an affordable way to upgrade to First Class.
“Our shared commitment to delivering exceptional journeys means that more travellers will now have the opportunity to experience the comfort and quality of the best seats on the train.”
The Seatfrog app allows passengers to place a bid or instantly upgrade their journey.