Not well. Vanguard required a US address but after establishing the account it was possible to report "moving" to Japan and still maintain the account (including maintaining it with the Japanese address).Does anyone have experience applying to Vanguard from Japan? How did it go?
Although I started the accounts before moving to Japan, both Fidelity and Schwab allow me to continue holding accounts with them. They will not sell me any mutual funds but they allow all stock trading including ETF's.
TD Ameritrade allowed me to initiate an account with them while living in Japan without any trouble.
Once you have one of those accounts you can by the ETF equivalent of Vanguard's excellent index mutual funds by looking up symbols on the Vanguard website (VOO, VTI, VT, VWO, etc.)
You don't have to live in the US to be able to contribute to an IRA. You do have to have "earned income" and if you take the earned income exclusion when filing US taxes you may find that you don't have "earned income" from a US tax perspective.I have never worked in the US, so I don’t have a 401k or IRA