I have used the trainline.com a couple of times, with no issues, except for my error in inputting the wrong return date, so my fault.
However, I resent the £1 booking fee and £3.50 credit card fee, that they charge you, are better on going onto one of the train operator websites and getting the information there.
I travel lot by train and have found it often cheaper to go to the operators website (especially where it only involves travel on that one operator).
For example: Berwick_Upon-Tweed to Portsmouth was advertised at £70 on the trainline.com, £1 booking fee and £3.50 credit card fee to making a price of £74.50. East coast mainline website £67.50 (their website price only), no booking and no credit card fees. Savings of £7.
Portsmouth to Victoria £15.90 Super off peak single on trainline.com, plus the £4.50 charges. Southern Railways managed to book in advance (only available on their website) for £10 no charges (can be £5 if booked far enougth in advance), so saving £9.40.
I would imagine that its similar on the other operators websites.
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