Train from Paddington Station in London to Bath Spa station

Just done a search. A one way ticket tomorrow is £33 per person. A one way ticket three months from now is £17 per perosn. So yes, book in advance.

Also, booking in advance guarantees you a seat on the train. It's not always easy to find seats on mainline trains, particularly seats together if you're in a group.

A train is never sold out - you will always be able to buy a ticket for a train, it's just you may have to squeeze into a rammed carriage or wait for another one. Booking in advance guarantees you a seat on your preferred train.

Could one of the prices be a typo in the above advice? "A one way ticket tomorrow is £33 per person. A one way ticket three months from now is £17 per person" This indicates that you'd save almost half by waiting three months, yet the info I've always seen is that you save by buying in advance. And the comment advises buying in advance -- explain?

Since you have a set plan booking "Advance" tickets now makes sense. And I do mean NOW. Advance is not a word meaning prior to , it is the name of a specific type of cheap ticket. The price goes up as the train fills up until the quota has sold out. In fact £17 isn't the lowest fare, on the 19th there are some back to London for £14.50 - at the moment. But beware, "Advance" tickets are fixed reservations and cannot be cancelled or altered later, whereas "Anytime" and "Off-Peak" tickets bought in-advance can.

nationalrail is official (run by the train operators trade association) but it's only an info site and if you click the buy button it will suggest sites you can buy from. You may as well use the actual train operator https://www.gwr.com/ although the site design is poor and it is a little slow. They have an M-Ticket option which downloads tickets to Apple or Android devices, whether this works with a non UK phone number I have no idea (not everybody at GWR realises that there are other countries in the world......). They probably offer a ticket on departure option which means you reserve and pay now then collect the tickets from a ticket machine at Paddington. If you use this you must insert the same payment card to prove it is you. If GWR can't cope with foreign credit cards try another train operator such as https://www.crosscountrytrains.co.uk/ (apart from certain short term offers, all operators sell all tickets, but beware the 3rd party agents like trainline because they have hidden fees).

Could one of the prices be a typo in the above advice? "A one way ticket tomorrow is £33 per person. A one way ticket three months from now is £17 per person" This indicates that you'd save almost half by waiting three months, yet the info I've always seen is that you save by buying in advance. And the comment advises buying in advance -- explain?

Clearly the price isn't going to remain at £17 the closer you get to departure!

epltd,

a one ticket bought now for tomorrow is £33.10 (on certain quiet trains), a one way ticket bought now for a date in 3 months may well be £17, in fact it could be even cheaper.

Yes, buy your ticket now. We are traveling to the UK in September also. Bought our tickets in June.

Absolute rock bottom price for a standard class Advance (excluding any special sales) for Paddington to Bath is £14.50. Possibly only seen the first day it becomes available. £17 is the next cheapest.