JJapan Finance

Seeking Investment-Related Advice for Japan & America

  • November 16, 2025

Hello, I’m a Japanese citizen currently residing in Japan, but I’m planning to move to the U.S. in a few years for more than a decade once I receive my green card. I don’t know a whole lot about investing in general, but I’m interested in using tax-advantaged accounts (NISA in Japan or Roth/Traditional IRAs in the U.S.) to invest in the S&P 500 for retirement funds.

I’ve done some research, and from what I understand, if you’re a U.S. green card holder (which I will be in the future) or a U.S. citizen, you can't buy additional stocks due to the QI system (https://search.sbisec.co.jp/v2/popwin/info/home/pop6040_kokuseki_02.html). Because of this, I haven’t bothered opening a NISA account.

Additionally, once I leave Japan for more than a year, I will likely no longer be considered a resident of Japan. In that case, I may need to close my Japanese bank and brokerage accounts, which means I’ll have to withdraw all investments currently in my WealthNavi account (a regular taxable brokerage account) before moving to the U.S.

So while I’m still in Japan, I plan to continue investing via just WealthNavi, but once I move to the US, I'm going to open a brokerage account on either Schwab or Vanguard to start either Roth or Traditional IRA and regular non-tax advantaged accouns. However, I’m planning on coming back to Japan till my retirement once my kid graduate an elementary school in the US. I’m not sure whether I can keep my U.S. brokerage accounts, continue investing, and withdraw funds once I retire in Japan. I’ve heard that I may not be able to contribute to a Traditional IRA unless I have taxable U.S. earned income, which I won’t have at that point.

Potential Plan A

  1. Keep investing through WealthNavi and withdraw the funds when I move to the U.S.
  2. Open a Roth/Traditional IRA and a regular U.S. brokerage account, and reinvest the withdrawn funds there
  3. When I leave the U.S. and move back to Japan, withdraw everything. I understand that I may need to pay taxes and early withdrawal penalties for the IRAs, and taxes on gains in the regular brokerage account
  4. Open a new Japanese brokerage account and reinvest the withdrawn funds, then withdraw everything when I retire. (I won’t be able to do NISA for the reason I mentioned above unless I forfeit my green card)

Potential Plan B

  1. Keep investing through WealthNavi and withdraw the funds when I move to the U.S.
  2. Open a Roth/Traditional IRA and a regular brokerage account, and reinvest the withdrawn funds there.
  3. If possible, continue investing from Japan and withdraw the investments when I retire in Japan. If I can't contribute to an IRA due to not having taxable U.S. earned income, then I would invest only in a regular taxable brokerage account while in the U.S.

I’m not sure if anyone has faced a situation similar to mine, but I’d appreciate any advice on what the best course of action might be, who I should reach out to for these questions, and any tips to make the most of my investment options given these limitations.

by Chester1182