UK rail refunds must be requested no later than 28 days after departure. Whilst not all tickets are refundable, you can check your options depending on the fare you selected:
Off-Peak / Super Off-Peak / Anytime fares: These tickets can be refunded through Your Bookings, minus a £5 fee set by the UK rail operators. You will need your booking reference fee to do this.
Advance fare: Ticket is non-refundable. Ticket can only be exchanged for another Advance ticket, for the same journey and by the same route, and on payment of any difference in price. The exchange must be made before the time on the original ticket. This can be done by making a replacement booking via your original point of sale and then contacting the Customer Service team with both sets of tickets for the exchange.
Customer Service: +44 0800 066 8528