The key factor is that the bank is licensed and located in Thailand, regulated by the Bank of Thailand (BOT), not necessarily Thai-owned. Foreign-owned banks operating branches or subsidiaries in Thailand, such as UOB (United Overseas Bank, Singapore-based but with a full Thai subsidiary), qualify as long as the account is opened in Thailand and holds THB. UOB Thailand is commonly used by expats for this purpose, including for retirement visa extensions, and there are no official restrictions based on foreign ownership. Other examples include HSBC, Citibank, or Standard Chartered, which are also accepted. Purely Thai-owned banks like Bangkok Bank, Kasikorn Bank, or Siam Commercial Bank are equally valid but not required over foreign-owned ones.
Mark Levy all UK citizens are UK residents, but not all UK residents are citizens. As a citizen when you leave the UK you can relinquish your 'tax residency' but not your 'residency'.
Mark Levy it is confusing as legalese and common parlance can be quite different. 'Residence' pertains to your rights not your location. You can be resident in multiple countries simultaneously but may or may not physically be located in any of them. 'Tax Residency' is a separate concept and pertains to your liabilities. You could be liable for taxes independent of your 'residency' and or your location. I'm a resident of both my home country and my wife's home country but live in neither.