You perhaps need to get past the junior staff in the banks' customer service departments and talk to someone with more knowledge. Only householders receive council tax & utility bills etc, so that would mean that no one else in any household could open a bank account! Imagine a non-working spouse of a householder in the UK - no bills in their name, no letters from the tax authorities and so forever denied a bank account! Unlikely! Also, I suggest to search for UK bank accounts for non-reidents - that should turn up hits for banks' international sections which are more geared for people not able to produce the usual UK documentation. If all else fails then find a Thai bank which sends statements to you showing your address and open an account so you can use that as proof of address.