As regards US tax I did the following although I don't think there is anything legally binding to be done.
1. Ensured that I would be able to get hold of this year's info needed for tax filing the following year. This includes W-2's and 1099's - I did everything online so was sure that the following year I could get everything I needed online, so even though I closed a couple of savings accounts by cashing in CD's and I-Bonds I kept my online account active so the following February I could download the tax forms.
2. Converted my mutual funds in my after-tax accounts to ETF funds recognized by HMRC, and changed ownership into my wife's name only as she was going to be in a much lower HMRC tax band than me as I had US pensions and she had no income other than dividends and capital gains.
3. We both have IRA's so I made sure the brokerage we used would allow overseas customers.
4. Opened a US bank account that allows overseas customers as I have US private pensions, my wife has after-tax investments and we both have IRA's that we will be drawing. Plus when doing our US taxes the IRS deposits refunds into our US bank.
