Mary64

I'm new to the forum, so apologies if this isn't the optimum thread for my US 401(k) question, but it's the closest I could find. I'm a UK citizen and resident in my 60s, planning for my retirement here soon. I have a legacy 401(k) account from time spent working in the USA. I would like to use some of this pot to help fund a capital project as soon as I retire. I don't need all of the fund balance for that, so I'd ideally like to let the residual balance continue to grow tax-deferred for another few years before withdrawing the remainder (before I reach the age when I have to make required minimum distrubutions, as I'd rather make a clean break with the US system before that milestone). I've been getting clued up about the US/UK tax treaty (thanks in part to this forum) , which I may want to make use of. My query revolves around whether payments from my 401(k) would be considered either periodic or lump sums (i.e. non-periodic). I'm purely focusing on the UK perspective here, not the US angle. Based on the HMRC response to a prior post (by R Erskine) above, I would assume that my 2 withdrawals (say 3-5 tax years apart), would be considered non-periodic. Can HMRC please confirm how it would treat such payments ? Also, in my UK tax return after the initial 401(k) distribution, how would HMRC determine whether that single payment was going to be part of a periodic pattern, or just an ad-hoc lump sum? Would I just invoke the treaty and state in the return that this was a lump sum ? Thank you.