Moving from California to North Dakota: Residency, Taxes, and What to Prove

In California

California is both a major origin state, since many nurses domiciled here take travel contracts elsewhere, and the single highest-paying destination state for travel assignments. A nurse's tax home must be a genuine, regularly-returned-to residence with duplicated living expenses; nurses who claim a tax home in Texas or Florida but never actually go back risk having the FTB or IRS reclassify housing stipends as taxable wages if the facts show California, not the claimed state, is really home. A nurse domiciled outside California who works a temporary California assignment as a W-2 traveler does not become a California resident from that assignment alone, but the wages earned during the California contract are still California-source and must be reported on a nonresident Form 540NR.

In North Dakota

North Dakota's Bakken-region hospitals (Williston, Minot, Dickinson) are a real travel-nurse market, but the state has no published tax-home-specific guidance beyond the general 210-day/domicile rules. A nurse claiming North Dakota as a tax home while working assignment after assignment in other states faces the same general IRS tax-home scrutiny (Publication 463) that applies nationally; North Dakota itself has no special safe harbor for nurses.

In California

California is the most aggressive jock-tax state. FTB counts not just game days but practices, walkthroughs, and even voluntary workouts held at a California team facility during game week, which can turn one road game into three or four California duty days. With the Lakers, Clippers, Warriors, Kings, 49ers, Rams, Chargers, Dodgers, Giants, Padres, and Athletics all based here, nonresident athletes playing any California team face California nonresident tax on their duty-day-apportioned income, while California-domiciled athletes owe California tax on their full worldwide income.

In North Dakota

North Dakota has no major professional sports franchises, so it does not run a state 'jock tax' apportionment regime of its own. Athletes domiciled in North Dakota (a small number, given the state's size) owe North Dakota tax on their worldwide income subject to credits for tax paid to other states on away-game duty days, but no team is based in-state to generate reciprocal enforcement interest.

In California

The nine-month presumption under §17016 only creates a rebuttable presumption of residency past that point; it does not create a safe harbor below it. Spending fewer than nine months in California does not guarantee nonresidency; FTB still applies the closest-connections test. This is the classic dual-home audit target described across Bogleheads and r/tax threads: a retiree who keeps the California house, splits time with a Nevada or Arizona property, but leaves a spouse, kids, doctors, or the majority of actual annual days in California.

In North Dakota

The generous 210-day threshold is North Dakota's most distinctive feature for long visitors: someone who keeps a North Dakota home and spends up to 210 days in-state per year (nearly seven months) can still avoid North Dakota statutory residency, a materially longer runway than the 183-day states nearby (Minnesota) or in the Northeast.

In California

California has no convenience-of-employer rule like New York's. A nonresident who physically performs all their work outside California for a California-headquartered employer is not California-taxed on those wages solely because the employer is based here. The trigger is the employee's own residency and physical work location, not the employer's address. A California resident, however, owes California tax on remote wages regardless of where the employer sits.

In North Dakota

North Dakota has no convenience-of-the-employer rule. A remote worker who moves to North Dakota and works for an out-of-state employer is taxed by North Dakota as a resident on all income; the risk sits on the origin-state side if that state (e.g., a convenience-rule state like New York) still claims to source the wages there.

In California

California follows the federal Servicemembers Civil Relief Act and the Military Spouses Residency Relief Act. Active-duty military domiciled outside California but stationed here under orders are not California residents and their military pay isn't California-taxed. Under MSRRA and the Veterans Benefits and Transition Act, a nonmilitary spouse can elect the servicemember's domicile for state tax purposes instead of being pulled into California residency by physical presence alone.

In North Dakota

The 210-day substantial-presence test does not apply to U.S. military personnel who maintain a domicile elsewhere while stationed in North Dakota under orders, consistent with the federal Servicemembers Civil Relief Act. North Dakota also follows the Military Spouses Residency Relief Act for accompanying spouses.

In California

Federal law (49 U.S.C. §40116) limits taxation of air carrier employees to their state of residence and any state where they earn more than 50% of their pay, overriding ordinary duty-day sourcing. California hosts major crew bases at LAX and SFO, so this carve-out matters heavily for California-based flight crew who fly national or international routes.

In North Dakota

North Dakota has small commercial airports (Fargo, Bismarck, Grand Forks, Minot) but is not a hub base for major airline crews. Federal law (49 U.S.C. § 40116) still governs: crew wages are taxable only by the crew member's state of residence and, in limited cases, a state where more than 50% of pay is earned, so North Dakota's low top rate makes it an attractive domicile choice for any crew member who does live there.