Canadian on a K-1 Fiancé(e) Visa: The 90-Day Clock and Your First U.S. Tax Year

The K-1 compresses everything. You enter the U.S., you must marry your American fiancé(e) within 90 days, and then you adjust status toward a green card — all while moving your entire life. Which means the K-1 does something no work visa does: it stacks your arrival, your wedding, and your change of tax status into a single, chaotic calendar year, usually with no employer, no HR department, and no one whose job it was to mention taxes at all.

Here's how a K-1 year actually works on the tax side.

December 31 is the only date that matters for filing status

U.S. filing status is decided by your marital status on the last day of the year. Marry in your arrival year — which the 90-day clock virtually guarantees — and for that entire tax year you're "married" in the IRS's eyes. Your American spouse can no longer file single, and the two of you face a real decision:

• Married filing jointly, by electing to treat you (the arriving Canadian) as a U.S. resident for the full year. Usually the better rates — but it pulls your worldwide income for the whole year into the U.S. return, including everything you earned in Canada before you moved, reconciled through the foreign earned income exclusion or foreign tax credits.
• Married filing separately, keeping your pre-arrival Canadian income out of U.S. scope, at generally worse rates for your spouse.

Neither is automatically right. Big Canadian income before the move pushes one way; a high-earning American spouse pushes the other. It's an hour of modeling that routinely moves thousands of dollars.

Each spouse must report their entire worldwide income for the year you make the choice and for all later years unless the choice is ended or suspended.

SSN, or ITIN while you wait

After marrying you'll apply for work authorization and adjustment of status, and eventually a Social Security number. But tax season doesn't wait for USCIS. If the return comes due before your SSN exists, you'll file with an ITIN application (Form W-7) attached to the return itself — routine, slow, and blindsiding for couples who first hear of it in April. If your SSN arrives before filing, use it and skip the ITIN entirely. Timing your filing (including a simple extension) around the SSN can save the whole detour.

You still owe Canada a proper goodbye

The romance doesn't exempt you from the exit paperwork every Canadian mover faces: a final Canadian return with a departure date, and departure tax — Canada's deemed sale of your non-registered investments on the way out. K-1 arrivals miss this constantly, because unlike a job transfer there's no relocation packet, no advisor, nothing prompting it. The CRA doesn't grade on sentiment. (The full arrival sequence is in I Moved From Canada to the U.S. — How Do I File My Taxes?)

And the accounts you left behind become U.S. paperwork

Once you're a U.S. resident — by election in the marriage year or by the green card that follows — the standard stack switches on: FBAR once your Canadian accounts top $10,000 USD combined (the full guide), the RRSP reportable but treaty-deferred, and the TFSA — which the U.S. taxes and papers heavily — best dealt with before the election takes effect, not discovered after. If you make the full-year joint election, note that it accelerates all of this: your accounts enter U.S. scope for the entire year.

The green card that follows has its own long game

Adjustment of status makes you a permanent resident — a U.S. tax resident by the green card test from that day regardless of day counts, and, years down the line, potentially subject to the long-term-resident exit tax if you ever give the card up. We cover that whole arc in the marriage and green card guide; the K-1 is simply the express on-ramp to it.

---

Related reading: - Canadian Marrying an American or Getting a Green Card - FBAR for Canadians Living in the U.S. - U.S. Taxes for Canadians, by Visa Type: The Complete Guide Hub