Great Western Coffee Shop

The First Great Western website will offer me an off peak return from Chippenham to Salisbury at ^22.70 (or a peak ticket at ^27.30), with a train departing at 11:09 and with a change at Bath Spa (11:24 to 11:35) into Salisbury at 12:32.  Is that best value?

Well, no. I could purchase a ^10.30 off peak return from Chippenham to Warminster, and a ^7.10 off peak return from Warminster to Salisbury - total price ^17.40 (peak tickets would add up to ^24.30). Perfectly allowed if a catch a train that calls at Warminster, and they all do.

There's a train 5 minutes earlier from Chippenham (at 11:04) but it's not offered to you at all unless you ask for extra options, then select "via Melksham" OR "Avoid Bath Spa" (note, you have to type the place names in - the site does not help you with suggestions).   The service offered is change at Trowbrige (11:23 to 11:53 there), and personally I would prefer to change at Westbury where there are better facilities, and more trains to Salisbury too in the event of disruption.

You'll be offered tickets via Melksham at the same price as via Bath for this train - however, if you buy Chippenham to Warminster via Melksham (off peak) and Warminster to Salisbury (off peak), you'll pay ^6.10 + ^7.10 = ^13.20 ... the peak sum is ^11.00 + ^7.10 = ^18.10.

These are significant and valid savings - from ^22.70 to ^13.20 is a 42% saving, but I doubt very much you would be offered it even if you asked at the ticket desk at Chippenham ... "I want to go to Salisbury and come back later in the day. Please sell me the cheapest tickets on which I can do that^.

Prices are calculated for a single adult traveller without railcard, standard class.