Residency rules, sticky taxes, and first-year steps (2026)
2026.1 Edition · Revised 2026-07-25 · DomusDay Research
The move changes the rate; the record decides whether it sticks. Missouri keeps taxing until domicile actually changes, and its 183-day statutory test stays live while any Missouri abode is maintained. Below: what follows leavers, and the Arizona steps that build the record.
Arizona taxes all income at a flat 2.5% — no brackets — and subtracts 25% of net long-term capital gains on assets acquired after 2011, putting the effective long-term rate under 1.9%.
Source ↗More than nine months in the state during a taxable year creates a rebuttable presumption of Arizona residency. For arrivals it works in your favor: the presumption and dated records anchor the part-year split.
Source ↗Arizona's homestead exemption — a $400,000 base, inflation-adjusted annually — attaches to the primary residence with no filing or recording required, unlike the declaration states.
Source ↗Arizona is the easy half. Missouri decides whether the move counts, and it decides on evidence — the two tests below stay live until the record closes them out.
The full rules, the audit program, and every source: the complete Leaving Missouri guide →
Top-bracket rates differ by 2.2%: Missouri at 4.7%, Arizona at 2.5% — an illustration at the top marginal rate, not an effective-rate calculation.
The first weeks in Arizona matter more than they look: each step below produces a dated document, and dated documents are what answer a Missouri examiner years later. Do them early and the record starts on your side of the timeline.
Arizona treats you as a resident for licensing once any trigger applies — seven months' presence in a calendar year, Arizona employment, voter registration, or children enrolled without nonresident tuition — and a license and registration follow.
Source ↗Vehicles are registered on becoming an Arizona resident, with Arizona liability insurance required; emissions testing applies in the Phoenix and Tucson areas.
Source ↗Voter registration requires Arizona and county residency; registration closes 29 days before an election and is available online through the MVD system.
Source ↗The Department of Revenue's residency procedure weighs vehicle registration, voter registration, property ownership, and a consistent permanent address — the same records the steps above generate.
Source ↗Arizona's homestead exemption — a $400,000 base, inflation-adjusted annually since 2024 — attaches to the primary residence automatically, with no filing required.
Source ↗Every vehicle operated on Arizona roads must carry Arizona liability insurance.
Source ↗Arizona is a community property state: property acquired by either spouse during the marriage is community property, with gift and inheritance exceptions — relevant to title, basis, and estate planning on arrival.
Source ↗The arrival year is filed on Form 140PY, the part-year resident return, splitting income at the residency change date.
Source ↗Everything Arizona asks of a new resident, on its own plate: the Moving to Arizona guide →
Every rule on this page traces to a statute, regulation, or agency publication, listed in full on each state's own plate.
A permanent place of abode maintained in Missouri fails the first element of the departure exception, and the exception is conjunctive — so resident status stays in place on the department's reading of §143.101 whatever the day count. What the record shows about the home, and when, carries the analysis.
Form MO-1040 with Form MO-NRI, which states the residency dates and computes the Missouri income percentage. A part-year resident is treated as a nonresident but may compute tax as if a resident for the whole year, and may use Form MO-CR instead — one individual cannot claim both.
2026.1 Edition · Revised 2026-07-25 · DomusDay Research