Advice, this is a long one.

nun- yes.....planning on living in the UK for good. Luckily my home state is Washington.....so no state taxes.....yet..... although they have certainly talked about it. Married and filing separately....my only concern was trying to stay out of the 25% bracket. My pension and eventual social security will come to just over $31K at todays prices. At some point I will be taking that TSP money which is all yet to be taxed. At that point almost any money I take out of my TSP will push me into that 25% bracket. I was thinking (possibly incorrectly) that most of the time.....or at least during certain years.....having the $72K threshold (filing US jointly) for bumping up to 25% would save money when pulling money out of the TSP since any I take out will be income.

nun- yes.....planning on living in the UK for good. Luckily my home state is Washington.....so no state taxes.....yet..... although they have certainly talked about it. Married and filing separately....my only concern was trying to stay out of the 25% bracket. My pension and eventual social security will come to just over $31K at todays prices. At some point I will be taking that TSP money which is all yet to be taxed. At that point almost any money I take out of my TSP will push me into that 25% bracket. I was thinking (possibly incorrectly) that most of the time.....or at least during certain years.....having the $72K threshold (filing US jointly) for bumping up to 25% would save money when pulling money out of the TSP since any I take out will be income.

Yes the higher tax bracket income is nice to have and you want to minimize RMDs when you hit 70.5. The number of combinations and permutations make things complicated. The thing is will the fact that you must file separately in the UK wipe out any advantages of joint filing in the US....I haven't though about that because I'm single.

Would people new to cross border tax want a course to teach them what they need to know, and how to complete returns for themselves?

Let me flag I'm a profesional tax person: and even though your question illustrates a problem tax people often face when pricing, I think it can be resolved. The problem in pricing is: does the customer want education so they can do it themselves, or a 'doing' service, or have they asked for both? Even worse, are they asking for the latter but expect the former to be free?  Think in terms of the latter being a third the price of a combination service.

Maybe however a solution which you will like (?) is a course, such that it teaches how to do everything for one-self if you want to. May I ask for your feedback? And in your answer, would you state your current expectation of how long the course would be (to cover everything you think is necessary), and what price you think would be attractive to people new to cross border tax situations.

[delivered remotely - that is book, workbook, videos, video conference one to one]
Many thanks.

Wow, that would be a project. The higher profile of US tax compliance might make all the work worthwhile.

Yes the higher tax bracket income is nice to have and you want to minimize RMDs when you hit 70.5. The number of combinations and permutations make things complicated. The thing is will the fact that you must file separately in the UK wipe out any advantages of joint filing in the US....I haven't though about that because I'm single.

Just confusing myself working on SS estimates and trying to avoid paying as much tax on them as possible. If what I put into a SS tax estimator is accurate...... If I were getting my pension now ($15348) at the same time as I was getting my SS estimate now ($16008)....filing separately would come up with a bit over $2000 owed on taxes since it has me for owing tax on 85% of the SS. Filing jointly is $0. Granted, I would still need to sell off $5-10K of the TSP or Vanguard funds to cover some expenses for the year. It could be a very very fine line to juggle things. I feel like I'm back in school in a confusing class hoping that it will all start making sense sometime....

Just confusing myself working on SS estimates and trying to avoid paying as much tax on them as possible. If what I put into a SS tax estimator is accurate...... If I were getting my pension now ($15348) at the same time as I was getting my SS estimate now ($16008)....filing separately would come up with a bit over $2000 owed on taxes since it has me for owing tax on 85% of the SS. Filing jointly is $0. Granted, I would still need to sell off $5-10K of the TSP or Vanguard funds to cover some expenses for the year. It could be a very very fine line to juggle things. I feel like I'm back in school in a confusing class hoping that it will all start making sense sometime....

But if you file jointly your wife will loose her ISA allowance etc etc and you'd have to include all her assets on your US taxes, it might be useful to have a spouse who is not subject to US tax at some point ......there are so many complications. But take things a step at a time.......first figure out yours and your wife's UK tax residency status.

A question on remaining domiciled in the USA and the NHS

As far as I read it you can remain domiciled in the USA if you don't intend to live in the UK permanently.  But if you don't intend to live in the UK permanently and only pay tax on the money you remit into the UK does that not exclude you from using the NHS without paying.

http://www.nhs.uk/chq/pages/1087.aspx?categoryid=68&subcategoryid=162

If you move to the UK, you will not be charged for NHS hospital treatment from the date that you arrive as long as:
you intend to live permanently in the UK, and
you have the right to live permanently in the UK or have a "route to settlement" that will allow permanent residence in due course
You'll be expected to prove that you meet these requirements.
Your spouse or civil partner and children under the age of 16 (under 19 if in full-time education) are also exempt from these charges if they live with you permanently.

ETA
Maybe you qualify as the spouse of your UKC wife.

nun......I just assumed I would be arising basis......UK is where I plan to live until I stop breathing. There are so many possible year by year complications. Wife losing ISA might be ok at first.....or not. We might end up selling as much of my TSP money as possible from 59.5 to 62 to avoid SS taxes. Why can't the world be simple? If I were KING....I would do away with the US deduction crap. Just take the taxes out from the wages etc I get......our taxes are really getting stupidly complicated and unnecessary. And I can't help but think that it helps the financially nimble (wealthy) to the detriment of others.  

Oh jeez Alan......I am planning on keeping my US insurance for at least a few years. But later.....who knows? As a step-father to a young nurse......each area is very much different in health care. Harrrogate...surprisingly not so hot even though they have the rep for being rich and snotty. She transferred to Leeds (Jimmy's) to get into the areas she is more interested in. Harrogate is run by a Trust which decides where money goes....Patients aren't necessarily the priority.

nun......I just assumed I would be arising basis......UK is where I plan to live until I stop breathing. There are so many possible year by year complications. Wife losing ISA might be ok at first.....or not. We might end up selling as much of my TSP money as possible from 59.5 to 62 to avoid SS taxes. Why can't the world be simple? If I were KING....I would do away with the US deduction crap. Just take the taxes out from the wages etc I get......our taxes are really getting stupidly complicated and unnecessary. And I can't help but think that it helps the financially nimble (wealthy) to the detriment of others.  

If the UK is where you intend to live permanently, and you spend little to no time in the USA then I find it hard it hard to believe that you can legally claim to be domiciled in the USA.

ETA
The advice you were given by the tax advisor in post 1 seems to also confirm this:

Even if you have decided to remain in the UK for the foreseeable future, you can still claim to have retained your domicile in the US if, ultimately, you have an intention of returning there.  

...... If I were getting my pension now ($15348) at the same time as I was getting my SS estimate now ($16008)....filing separately would come up with a bit over $2000 owed on taxes since it has me for owing tax on 85% of the SS.

If you are resident in the UK and collect US Social Security (have SS sent to the UK), the SS is only taxed in the UK, and then on only 90% of the gross amount if filing on the arising basis. It is not taxed, none of it, in the US.

A random thought from a UK citizen and retired, and who is still a US citizen filing US tax returns.

IF you intend to spend your remaining years in the UK, set up your sources of income with UK tax paid to HMRC as the MAIN priority. Be sure you're 'right' with HMRC, and don't complicate your UK return with the US return in the back of your mind.

If you set up all income sources wisely, in most years, you will not owe any US tax, regardless of what US 'tax % bracket' you fall in.

theOAP----Hell.....I'm even going so far as to join a "golf club"....that's how permanently I plan the move to be. Now the question.....and it's a big one....what are the intelligent steps leading up to this move...permanent move....like....ain't goin' back..... I WILL be domiciled in the UK....I will likely almost never, if ever leave the country.

The choice is yours.

You can be a US citizen, resident in the UK and file as non-domiciled. You can be a UK citizen, resident in the UK, and still be non-domiciled if your argument is strong enough. It would be up to you or your tax person to make the argument to HMRC. You have income sources from the US that will always remain from the US, pensions and Social Security.

A bit early to think about, but would you ever think about becoming a UK citizen?

Somewhere in depths of the HMRC site, is a page giving examples of determining domicile. It gives about 20 examples. Here's the one I remember the most:

A lady who was a US citizen married a Brit. She moved to the UK to be with her husband. She sold all homes and real estate in the US and moved the funds to the UK. She closed all bank and financial accounts in the US and moved the funds to the UK. She had no assets in the US.

She noted in her Last Will and Testament that if her husband died before her and was cremated, she wanted her body sent back to the US for burial. She never became a UK citizen. It was enough for the US to claim domicile, and not the UK. Times may have changed regards domicile since then, I don't know.

We are all individuals, and must make our own decisions. Mine was to remove all assets, other than US SSA, from the US, file 'married separately' in the US, and pay UK tax on the arising basis. I have not owed tax to the US since I retired.

I am all for giving up my US citizenship. Couldn't care less. My only concerns are for my pension and social security money. And....in my wife's case....her spousal SS income. I wouldn't want to take the chance of losing my US "money income". I don't plan on being any more than a "paper" US citizen.

I am all for giving up my US citizenship. Couldn't care less. My only concerns are for my pension and social security money. And....in my wife's case....her spousal SS income. I wouldn't want to take the chance of losing my US "money income". I don't plan on being any more than a "paper" US citizen.

Whoa! Again, that is a personal decision.

At the moment, the US tolerates dual citizenship. You can become a UK citizen without having to give up US citizenship. The UK also allows dual citizenship, so you can become British without a requirement to give up US citizenship.

I really can't think of any circumstance where citizenship becomes the determining factor for access to your "money income".

Several of us on this site are retired, are dual citizens, and have income sources from both countries. There are some on the BritishExpats site who are dual citizens currently living in the US and contemplating retirement in the UK with income sources from both countries. There are those on both sites who are dual citizens contemplating retirement with a plan to live part year in the UK and part year in the US.

It's an individual's decision, but one must cut their cloth according to their goals. Having to file a US tax return and a UK tax return is a complication most people in the world will not understand. Your goal may be to stay invested in the US, reap the largest financial rewards possible, and pay the least amount of tax possible to both countries (and all that entails). Or, your goal may be to keep it as simple as possible, but with the knowledge that you may pay more tax overall (usually to the UK) but relieving yourself from the stress of the balancing act; allowing you to enjoy your retirement in the UK.

It's not easy, but it will only be as difficult as you wish it to be. There is no one correct way for everyone in this situation. The 'epiphany' is the moment you determine your goal and what is important to you. Your aptitude for dealing with the potential complications will determine whether you employ a tax accountant, or you feel confident enough to self-file. A professional will always strive to make sure you pay the least amount of tax, both accurately and legally, today as well as planning for the future. By self-filing, you may pay more tax (or maybe not); but it may be offset by not having to pay professional fees. The key is knowing where the tipping point is between the two.