Is there stamp duty on a share transfer in a Thai company?

Yes. Duty is 1 baht for every 1,000 baht of the paid-up value of the shares or the value in the transfer document, whichever is greater, and the seller is liable for it. Check the Foreign Business Act position first: a transfer that makes the company majority foreign-owned can change what it is allowed to do.

Corporate changes

Source: Stamp Duty Schedule, The Revenue Department, Thailand