Brit Rail Pass for travel to Bath and Salisbury

the individual ticket from London to Bath alone is ~$150 per person at the times we would like to travel

Are you sure? I can see one way tickets London to Bath on 15 April from £26.30. What date(s) and time(s) are you looking at?

http://www.nationalrail.co.uk/

Yes, the tickets between 8am and 10am on 4/17 or 4/18. I think you might be looking at one that leaves Paddington at 11 am...

what website are you looking at to get your fare information?

The one off Rick's website, National Rail site, http://www.nationalrail.co.uk/.

Swat, I went to: http://www.nationalrail.co.uk/
From London to Bath, date 17/04/2019 (Wed 17th April), time: 08:00, and I got the following answers (departure time and price per person, 2nd class):

08:00 £101.50
08:30 £101.50
09:00 £50.10
09:30 £45.50
10:00 £27.50
10:30 £35.40
11:00 £21
11:30 £21
12:00 £21

Journey time in all cases 1h30 or a few minutes less, direct trains.
Yes, you are paying more to travel at peak times (before 10:00). Cheaper seats are available at those times if you book earlier (1-2 months in advance). I suggest you travel 10:00 or after.

Or you could take the coach to Bath for £7

https://www.nationalexpress.com/en

Thanks, Chris, for pointing out that website. Will investigate further! What website should I use to look for ticket prices/schedule from Bath to Salisbury and Salisbury to London, same one?

£101.50 is the cost of an Anytime Single from Paddington to Bath, ie the most expensive standard class ticket there is on the route. It is questionable whether there would be any cheaper fares made available on that train, although there may have been if you had booked some weeks, possibly months ago.

Wait until the 09:00 train and all three of you can travel on it AND cover the cost of your return journey via Salisbury for a total of £162.90 as this is (just) into off-peak, it is a return ticket, and because there are 3 adults you can get 34% off, ie in effect it is 3 for the price of 2. Just book the ticket from London TERMINALS and ANY PERMITTED route.

(There may be other ways to get further reductions (possibly) by split ticketing etc, but this is more complicated because you are using two different routes to / from London).

Your pass price is correct. That 2-day full BritRail version is cheaper than the regional versions that start from 3 days. If you had anything to use it for on the day before or after this excursion, such as an airport express train or other destination, then of course you'd get more value from it.

It looks like the 3 day BritRail South West pass might be slightly less expensive than the BritRail pass - 2 adults and 1 youth price is $248. From looking at the map it appears to cover the areas you want to go and the pass gives you the freedom to be flexible with your timing.

You might also try the Britrail London Plus Pass. It gives you 3 days in a month to cities a certain distance from London. I used the pass several years ago to go to Salisbury and Bath on two separate days, but you can use it as many times as you want in one day. You can also use it on the Heathrow Express to get into the city. That uses a day. It is very handy because you can hop on and off any train on the days you choose.

The BritRail London Plus Pass does not cover the direct train route from Bath to Salisbury. See the map at https://www.ricksteves.com/travel-tips/transportation/trains/britain-rail-passes.

The BritRail South West Pass works if you they can use 3 travel days but is not any cheaper for this group; it costs $297, versus the 2-day pass at $279.