Moving from California to Michigan: 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 Michigan

Michigan applies its ordinary domicile and 183-day deeming rule to a travel nurse the same as anyone else: a nurse who lives in Michigan at least 183 days in a tax year is statutorily deemed a Michigan domiciliary regardless of a claimed out-of-state tax home. The more frequent exposure runs the other way, where a nurse claims a Florida or Texas tax home while actually renting in Michigan for most of an assignment; Michigan and, where applicable, a Michigan city both tax nonresident wages for days actually worked in the jurisdiction regardless of the claimed tax home.

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 Michigan

Michigan and the City of Detroit both tax nonresident professional athletes on a duty-day basis. Detroit's jock tax, formally codified in 2017, applies its duty-day apportionment broadly, reaching injured players who travel with the team as well as coaches, trainers, and other team personnel required to travel and perform services, not just players who take the field. This applies to visiting teams playing the Lions, Pistons, Tigers, and Red Wings.

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 Michigan

The Michigan snowbird risk runs directly through the Principal Residence Exemption and the 183-day deeming rule together. Campbell v. Department of Treasury shows that simply acquiring a second home in a state like Arizona, without more, was enough for Treasury to deny the PRE on the Michigan home for the following tax year, and Treasury's three-year lookback on PRE claims means a snowbird's arrangement gets checked retroactively, not just going forward. Separately, spending at least 183 days in Michigan in a year, even a retiree splitting time between an Up North cottage and Florida, statutorily deems that person a Michigan domiciliary for the year.

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 Michigan

Michigan has no convenience-of-the-employer rule at the state level. A nonresident who works remotely from another state for a Michigan-based employer is generally not taxed by Michigan on those wages, since the state sources employee compensation to where work is physically performed rather than to the employer's location; the same principle generally applies to Michigan's local city income taxes.

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 Michigan

Michigan follows the federal Servicemembers Civil Relief Act and Military Spouses Residency Relief Act. A servicemember whose domicile was Michigan before entering service remains a Michigan domiciliary regardless of duty station unless they affirmatively establish a new domicile, while a servicemember stationed in Michigan on orders, and a qualifying spouse, does not become a Michigan resident solely because of the posting.

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 Michigan

Federal law (49 U.S.C. §40116) limits states to taxing airline employee compensation only in the employee's state of residence and any state where more than 50% of pay is earned, protecting flight crew based at Detroit Metro who are domiciled outside Michigan from full-income Michigan taxation based solely on their duty station.