US ↔ Japan money, from someone who lived it.
I'm Jin — a Japanese national who spent four years working in the US. Most money guides are written for people staying put. This one isn't. Here I work through the cross-border problems that don't get covered well anywhere: keeping a US brokerage after moving to Japan, the phone/2FA trap, PFIC, cross-border tax — from my own research and real numbers, not generalities.
One person's record — not investment or tax advice. Rules vary by firm, account, and timing.
Bank 2FA without a US phone number: which logins actually work on an authenticator app
Most US banks now support authenticator apps for 2FA, but password resets still need SMS. Here's how to switch each account type before leaving the US.
California taxes after moving abroad: the 546-day safe harbor and why "move to South Dakota first" backfires
California taxes residents on worldwide income, even after you move. Learn the 546-day safe harbor rule and why the popular South Dakota strategy often fails.
Claiming US Social Security while living in Japan: totalization, the WEP repeal, and who actually pays you
How the US-Japan totalization agreement combines Social Security credits from both countries for eligibility, and how the WEP repeal affects your benefits.
HSA after leaving the US: the account everyone forgets when they move to Japan
Your HSA survives the move to Japan with tax-free growth. You lose contribution rights, but qualified withdrawals work for medical expenses with receipts.
Working remotely for a US employer from Japan: who taxes your salary (hint: Japan, and it's not the 5-year rule)
Remote work salary for a US employer is Japan-taxed if work is done in Japan. Covers permanent establishment, FICA, and Foreign Tax Credit implications.
How Japan taxes your Roth IRA: the tax-free account that isn't (here)
Japan doesn't recognize Roth IRAs as tax-free accounts. Under the US-Japan treaty, annual gains aren't taxed, but growth is taxable at withdrawal.
Can you use an American credit card in Japan? Yes — and with a weak yen, spending USD directly can beat converting it
Compare costs of spending US dollars in Japan with a weak yen: credit card fees (0-1%), bank transfers (3-5%), cash exchange (3-16%), and DCC traps.
US taxes married to a Japanese citizen: the "NRA" box, when you need an ITIN, and when filing jointly backfires
Filing options for US citizens married to Japanese nationals: Married Filing Separately (no ITIN), Married Filing Jointly (requires ITIN), or Head of Household.
W-8BEN vs W-9 after you move: the one form that decides your US dividend withholding (30% or 10%)
Your tax status, not address, determines Form W-9 or W-8BEN. Nonresident aliens claiming US–Japan treaty on W-8BEN pay 10% dividend withholding instead of 30%.
Does Zelle work internationally after you leave the US? The P2P apps that break at login
How Zelle, Venmo, and PayPal work after moving abroad. What breaks at login, what to set up before you leave, and alternatives for international transfers.
Federal student loans when you move abroad: the $0 IDR payment, explained
How FEIE reduces federal student loan payments to $0 on income-driven plans while working abroad. Key caveats: interest keeps accruing, forgiveness is taxable.
Moving between the US and Japan: the complete money guide
Complete guide to US financial accounts when moving to Japan: keep your phone number and address, manage brokerage accounts, navigate tax traps.
Japan's inheritance tax and your US family: the 10-year rule that decides whether Mom's IRA is taxable
Japan taxes heirs, not estates. Whether inherited US assets are taxable depends on your visa and time in Japan. Overview of the 10-year rule for US families.
Moving your savings from the US to Japan: wire vs Wise vs just leaving it
Compare ways to transfer US savings to Japan: Wise for small amounts, SWIFT wires for large transfers, and the option of leaving money in the US.
Opening a Japanese bank account as a new foreign resident: what actually gates you (and how to bridge the first weeks)
Open a Japanese bank account as a foreigner: residence card, address registration, and phone number requirements, plus bridge strategies for new arrivals.
Giving up your US green card: I-407, the 8-year line, and the exit tax question most people miss
Guide to I-407 filing timing, the 8-year long-term resident rule, Form 8854 requirements, and covered expatriate exit-tax thresholds for green card holders.
529 plans when you move to Japan: keep it, cash it out, or hand it to grandpa
Japan doesn't recognize 529 tax benefits. Decide whether to keep your account growing, cash out and pay the penalty, or transfer it to a US-resident relative.
Selling your US home before moving abroad: the Section 121 timing window most expats miss
Home-sale capital gains exclusion up to $250k/$500k with 2-of-5-year ownership rule. Understand when to sell and tax residency timing for expats moving abroad.
Japanese pension for Americans: enrolling, the totalization exemption, and the lump-sum trap
Mandatory pension enrollment if registered in Japan. The US–Japan totalization agreement combines coverage periods. A Certificate of Coverage can exempt seconded employees.
The US tax calendar for Americans in Japan: every deadline, in order (April 15 → June 15 → October 15)
Reference guide to US tax filing deadlines for Americans in Japan, covering the June 15 extension, FBAR, and how the two tax calendars intersect.
Moving back to the US from Japan: the reverse checklist most guides skip
Repatriation guide from Japan to the US: Japan exit taxes, banking decisions, credit rebuilding, US return-year planning, and currency conversion timing.
Health insurance across the move: the coverage gap, COBRA, and the second-year premium spike nobody plans for
Navigate the insurance gap when moving to Japan. Bridge with travel coverage, enroll in mandatory NHI, and prepare for the second-year premium spike.
Buying a home in Japan as a US person: the mortgage, and the yen-loan tax trap nobody warns you about
Buying a home in Japan as an American: mortgage access, ownership costs, and the hidden IRC §988 tax trap when the yen weakens on your foreign-currency loan.
TreasuryDirect and I bonds from abroad: the locked account nobody plans for (and the 16-week unlock)
TreasuryDirect blocks new accounts from abroad. Existing accounts lock when you move. Unlock via FS Form 5444 with notary. Embassy processing takes 16 weeks.
Keeping your US credit score alive from abroad (you'll want it back the day you return)
Keep your US credit alive abroad: downgrade old cards instead of closing, autopay charges, maintain anchors, freeze credit, avoid costly consequences on return.
Medicare when you move abroad: keep Part B or drop the $202.90/month you can't use?
Part B covers nothing abroad but carries re-enrollment penalties if dropped. The decision hinges on whether you'll return to the US for care.
How much money should you save before moving to Japan? A real-numbers breakdown ($8k–$22k)
How much to save before moving to Japan: $8k–$22k total. Covers apartment move-in, flights, visa, setup, living buffer, emergency fund, and ongoing US costs.
Getting into your IRS online account from abroad: ID.me without a US phone number
Access your IRS account from abroad without a US phone. ID.me verification using authenticator app, international documents, and video call with passport.
FBAR from Japan: which Japanese accounts actually count (NISA, iDeCo, Yucho, pension)
US persons in Japan filing FBAR: which Japanese accounts are reportable. Covers bank accounts, NISA, iDeCo, Yucho, and excludes government pensions.
Does Japan tax your foreign income? The 5-year rule and remittances, explained
For the first 5 years in Japan, foreign income is taxed only when remitted. But salary earned in Japan is always taxable, regardless of remittance status.
Your US will and your Japanese assets: the non-citizen spouse problem nobody explains
Non-citizen spouses lose the unlimited marital deduction. Here's what QDOT trusts, gifting limits, dual taxation, and beneficiary designations mean for cross-border estate planning.
Japan crypto tax: the 55% problem, and why your US exchange will drop you when you move
Japan taxes crypto gains at 55% as miscellaneous income with no loss carryforward. Understand taxable events, exchange closures, and pre-move strategy.
RSUs and stock options when you move to Japan: the vesting period decides who taxes what
Where equity is taxed when moving to Japan depends on where you worked during the vesting period, not where you live. Both the IRS and Japan's NTA claim their share.
Japan's residence tax: why your second year costs more than your first
Japan's residence tax is assessed on prior-year income and billed from June. Your first year is nearly tax-free, but year two brings the prior year's bill.
FEIE or the Foreign Tax Credit in Japan: why the default choice is often wrong
US expats in Japan often default to FEIE, but Japan's high taxes make the Foreign Tax Credit a better choice—with a five-year lockout if you revoke it.
Keeping US credit cards without a US address: what actually works (and what quietly breaks the terms)
Realistic options to keep US credit cards after moving abroad: address solutions, compliance risks, and strategies that don't violate card terms.
Locked out of your US bank from abroad: a recovery playbook
Locked out of your US bank overseas? Three recovery paths: call international support, get in-branch help, or use embassy notarization. How to fix 2FA.
401(k) and IRA after moving to Japan: leave it, roll it, or cash out?
Understand your US 401(k) and IRA options when moving to Japan: leave in place, roll over to IRA, or cash out—each with different tax and withdrawal implications.
Your first tax year after leaving the US: dual-status returns, FBAR, and the $10,000 line most people miss
US tax obligations when leaving mid-year: dual-status filing status, FBAR requirements at $10k threshold, Form 8938 disclosures, and state tax tail risk.
Changing your brokerage address to Japan: what actually happens at Schwab, Fidelity, and Vanguard
What happens when you change your US brokerage address to Japan. Account restrictions, fund purchase limits, and the safest sequence before leaving.
Google Voice vs a real US number for bank 2FA: why free sometimes fails at the worst moment
Google Voice keeps a US number alive for free — so why do some banks refuse to text it? How VoIP detection works, how to test your own accounts before you leave the US, and when a $5 real number is the safer anchor.
Porting your US phone number before you move abroad: keep it for about $5/month
Keep your US phone number when moving abroad by porting to an MVNO before you leave. Essential for 2FA and banking access. Costs about $5/month.
Can you keep your US credit cards after moving to Japan? The address, payment & login reality
Moving from the US to Japan and want to keep the US cards you spent years building? They don't auto-close — but three things get in the way: a US address, a US bank to pay from, and the SMS 2FA that dies with your US number. Here's the real picture.
NISA and US citizens: why Japan's tax-free account can be the opposite for you
NISA is a great deal for most residents of Japan — but if you're a US citizen or green-card holder, it can quietly become the worst of both worlds: still taxable to the IRS, and usually holding PFICs. Here's why, and what to weigh.
PFIC: why Japanese mutual funds (and NISA) can be a tax trap for US persons in Japan
If you're a US citizen or green-card holder living in Japan, that eMAXIS Slim fund or NISA holding can be a PFIC — taxed by the IRS at punitive rates with a yearly Form 8621. Here's what PFIC is, why it's so brutal, and what US persons actually do about it.
Keeping a US phone number after you leave: the 2FA problem nobody warns you about
Move abroad, your US SIM dies, and suddenly you can't log into your bank, brokerage, or credit cards — the 2FA code goes to a dead number. Here's what actually breaks, why VoIP isn't enough, and how to keep a real US number for a few dollars a month.
Can you keep your US brokerage after moving to Japan? I compared Schwab, Fidelity, Vanguard & IBKR
Moving from the US to Japan and wondering if your US brokerage survives the move? A first-hand comparison of Schwab, Fidelity, Vanguard and IBKR — the 'held but frozen' trap, the US-address myth, the 2FA problem, and how to open an escape hatch before you go.