I've used Transferwise recently. £10,000 each time to my account at krungsri Bank. It was lower commission than Natwest Bank (my bank) offered. 

 

Do you you know of any cheaper money transfer services?

 

 

No. All I checked out and the amount of Baht you get is better than any other option I could find.

I also use Transferwise to bring money from the UK and it's the best rate I can find, although I also have an Easy FX account and their rates are very close to Transferwise.

 

For example, at this morning's rates, sending £1,000 via Transferwise would give me 43,796 baht and via Easy FX is 43,225. Both still much better than UK banks rates.