What are the challenges of updating UK pensions and addresses while moving to Thailand?

I use my sisters address

Changing your residential address from the Uk to Thailand is mostly unnecessary.. and frought with danger.. firstly, if you advise the DWP (govt pensions unit) you no longer consider the Uk to be your permanent home.. you will immediately lose the indexation attached to your state pension.. secondly, you should maintain a Uk bank account registered to a Uk address.. and have any Uk pension or other income paid into that account initially.. that way you can control how much money you bring into Thailand and when.. which could become very important if you are deemed tax resident in Thailand.. and thirdly, some Uk banks are forcing closure of accounts held by expats who try to register their overseas address.. this very action triggers a review and unless you happen to be a 'premiere' customer with substantial funds on deposit.. they will likely ask you to close it.. it's better to simply change your address to a relatives residence. then toggle all communications from your Uk bank to email thereafter.. this also necessitates maintaining a Uk mobile number for OTP's.. as well as communications with other Uk centric organisations.. and this can be done very easily by porting your number from a physical network to a VOIP service.. offerings such as Expatfone will even give you free voicecalls back to the Uk.. and will also shield your location so nobody will know you are not in the Uk when making or receiving calls.. useful if you need to call your Uk bank to resolve an issue.. and if you later decide Thailand is not for you after all.. you haven't burnt your britches so to speak.. lastly, you may want to return to the UK for medical reasons in the future.. given that there is no NHS equivalent in Thailand.. and treatment for more complex conditions (or surgeries) can be expensive here if you dont have health insurance.. so keeping the door open to access the NHS would be prudent.. as a British citizen that may still be possible in the short term.. but one day the govt may decide to start charging non-residents in the same way as they charge foreign tourists.. so maintaining a UK address for as long as possible would make sense.. at least imo!

Same routine with my forces pension also. 5 yrs to wait for State pension

My advice? Do not burn your bridges.

What I did and with my pensions was keep them going into my Natwest bank and transfer the money through Wise to Thailand. I changed my address to my Thai address with the bank, pension company, DWP and HMRC that was 10 years ago maybe it was easier then.

You would be wise to maintain your UK bank accounts and have your pensions paid in there. You also need to inform the state pension people of your Thai address, I had to do that for pension and overseas landlord status but I don't remember having to provide any proof of address. Probably best to call them and explain

Don't bring any pensions here, keep an address in the UK if you can, family member ?

I use my brothers address and registered myself on electoral role and put my UK banks on that address

Proof of Residential Address in Thailand is now a problem. Many UK Institutions no longer accept Certification by Thai Notaries. The only way is via a zoom call to your financial advisor or certification by a UK solicitor.

I found it better to email them with change of address and they responded but if you are already out of the UK then you need to go on the International pensions website