UK spouse Social Security spousal coverage

[F4mandolin]

If she is an NRA (not a US Citizen), she would not be required to file a US tax return if her only source of US income is US SS. She would also only pay tax on the US SS amount to the UK (HMRC), and none to the US (and none would be withheld by the SSA).

If she is a US Citizen, she would be required to file a US tax return (if she met the threshold, but in this case, you would probably file MFJ). She still would not pay any tax to the US on the US SS amount, and would only pay tax on the US SSA pension to the UK (HMRC).

These kinds of things might also dictate where we move our money to as well. I would likely stick with the TSP money in my name, but then couldn't I move what would be left of our Vanguard money into her name only (with the appropriate Vanguard ETF's). Until she hits 67, she wouldn't even have to leave the UK Personal tax allowance on small withdrawals of money from that. I could just take any money we needed out of the TSP (and pay the minimal tax on that...15%).