Heathrow to Bath

Have you read the information on the tour page?

Take the bus from Heathrow to Reading, change there to a train to Bath.

Same as Badger. Bus to the Reading train station and train to Bath.

If you were already in London you could take the train from Paddington to Bath Spa (BTH) for £33-£38 approximately depending on date, time, and when you buy the ticket. The train station in Bath is about a 10 minutes walk from the Abbey and historic center. Any train leaving Heathrow will go to Paddington which is why the others recommend a bus then switching to train. The trip from Paddington to Bath is about 1hr 20min.

The link to the train schedules is: www.gwr.com

You can also take a train from Heathrow terminals two, three and five and transfer at London Paddington. Total trip takes 2h: https://reiseauskunft.bahn.de/bin/query.exe/en?ld=4341&country=GBR&protocol=https:&seqnr=1&ident=25.01385541.1622765110&rt=1&OK#hfsseq2|25.01385541.1622765110

There is also a direct bus from Heathrow to Bath. The bus station in Bath is next to the train station.

https://www.nationalexpress.com/en/destinations/bath/heathrow-to-bath

Yes, the National Express coach is also a very good option. Forgot about that one.

Depending on how many people a pre-booked private hire car / minicab might not be out of the question on cost, or indeed you might value the convenience. Not my area so I can't recommend a specific firm from experience but the cost seems to range from £125-150.

Plenty of people use the bus or train or a combination to get to Bath. But since you asked for the best way, in my opinion the best way is a private car service. Not the cheapest, but the best. We've used car services in different locations and our experiences have been that using a service based in the destination city works well as they always seem to know "the best way home". We used one based in Bath to go to the Bristol airport but we would not hesitate to use them from Heathrow to Bath. The web site (if memory serves correctly) is chauffeurtravel.co.uk and the email address is enquiries@chauffeurtravel.co.uk. We sent an email detailing our needs and had a reply within 24 hours. Not sure about the price since we didn't actually go from Heathrow to Bath, but by the time you total up bus / train fares, the hassle factor, time involved, all while being jet lagged on unfamiliar turf, it's a small luxury we feel is well worth the price. This is especially true if you have more than just one or two people involved.