Arizona's 9-Month Residency Presumption

Q: How many days can you spend in Arizona before being presumed a resident?

Up to nine months in the aggregate during the tax year. Spending more than nine months in Arizona, roughly 270 days, creates a rebuttable presumption that you are an Arizona resident. It is a presumption, not an automatic rule, so it can be overcome with evidence that you were in the state only for a temporary or transitory purpose.

Q: Can the Arizona nine-month presumption be rebutted?

Yes. The presumption may be overcome by competent evidence that the individual is in Arizona for a temporary or transitory purpose. The day count shifts the burden onto you, but it does not by itself make residency final.

Q: What counts as time spent in Arizona for the nine-month rule?

The statute looks at time spent in the aggregate across the whole taxable year, so periods do not need to be consecutive. Roughly 270 days, or more than nine months of the year, is the point at which the presumption of residency arises.

Spending more than nine months of the tax year in Arizona, roughly 270 days, presumes you are a resident. It is a presumption you can rebut, not an automatic rule. Here is exactly how the count works.

Last verified: July 2026

In short: Arizona presumes you are a resident if you spend, in the aggregate, more than nine months (about 270 days) of the taxable year in the state. This is a rebuttable presumption: it can be overcome with competent evidence that you were in Arizona only for a temporary or transitory purpose. Crossing the nine-month mark does not decide residency by itself, but it shifts the burden onto you.

Threshold: More than 9 months (about 270 days)
Presumption: Rebuttable, not automatic
Counting window: Calendar (taxable) year
Time is counted: In the aggregate across the year
Rebut by showing: Temporary or transitory purpose
Legal basis: Ariz. Rev. Stat. §43-104

The rule

Arizona defines a resident in several ways, including anyone domiciled in the state. Separately, Arizona law adds a presumption based on time spent. The statute states that every individual who spends, in the aggregate, more than nine months of the taxable year within the state is presumed to be a resident.

The key word is presumed. Unlike a hard statutory-resident line, crossing nine months does not automatically make you a resident. Instead:

More than nine months. Spend more than nine months, roughly 270 days, of the taxable year in Arizona and the presumption of residency arises. Time is measured in the aggregate, so the days do not have to be consecutive.
Rebuttable. The presumption may be overcome by competent evidence that you are in Arizona for a temporary or transitory purpose. If you can show that, you can be treated as a nonresident despite the day count.

In practice the nine-month mark shifts the burden onto you: below it, Arizona has to establish residency; above it, you have to disprove it.

How to count it

Count every day you were present in Arizona during the taxable year.
Add the days across the whole year. They do not need to be consecutive; the test looks at time in the aggregate.
Compare the total against nine months, roughly 270 days.
If you pass nine months, the presumption of Arizona residency applies unless you can rebut it with evidence of a temporary or transitory purpose.

Example. You are domiciled in Washington but spend the winter and spring in Scottsdale. Across the year you are physically in Arizona for about 285 days, well past the nine-month mark.

Because you exceeded nine months in the aggregate, Arizona presumes you are a resident. To be treated as a nonresident you would need competent evidence that your time in Arizona was for a temporary or transitory purpose, rather than as a settled resident.

Beyond the day count

The nine-month presumption is only one route to Arizona residency. Arizona can also treat you as a resident by domicile, which turns on where your true, permanent home is rather than a day count, and that can apply even if you spend far less than nine months in the state. Because the nine-month rule is a presumption rather than a bright line, the quality of your evidence, ties elsewhere, and the purpose of your stay all matter when it is challenged.

Official source: Arizona Revised Statutes §43-104, on the Arizona State Legislature definitions page, which provides that an individual who spends more than nine months of the taxable year in Arizona is presumed to be a resident, a presumption that may be overcome by competent evidence of a temporary or transitory purpose.

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FAQ

How many days can you spend in Arizona before being presumed a resident?

Up to nine months in the aggregate during the tax year. Past more than nine months, roughly 270 days, Arizona presumes you are a resident, though the presumption can be rebutted.

Can the Arizona nine-month presumption be rebutted?

Yes. It may be overcome by competent evidence that you are in Arizona for a temporary or transitory purpose. The day count shifts the burden to you but does not make residency final.

How is time in Arizona counted for this rule?

In the aggregate across the whole taxable year, so periods do not need to be consecutive. Roughly 270 days, or more than nine months, is the point at which the presumption arises.