Rulebook / Tax residency / United States
Iowa statutory residence
- Day threshold
- 183 days
- Window
- Calendar year (1 Jan – 31 Dec)
- Direction
- Ceiling — stay at or below
- Counts
- Days in Iowa; arrival and departure days both count
- Authority
- Iowa Department of Revenue
Iowa statutory residence caps your time in Iowa at 183 days per calendar year. The statute attaches its consequence at 184 days or more, so 183 is the last safe count. Statutory residence needs both a permanent home in Iowa and more than 183 days there. Days recorded only as "United States", with no state, are not counted — they are reported as unknown rather than guessed.
Who it applies to
This matters most if you are:
- A remote worker, digital nomad or frequent traveller spending long stretches in Iowa.
- An expat arriving in or leaving Iowa mid-year, where the days straddle a boundary.
- Anyone keeping a home in more than one country who needs a defensible day count for a tax return.
The rule — and why it exists
Iowa day count. At most 183 days in Iowa per calendar year — <=183 / YEAR. It only applies if: Do you keep a home available to you in this state all year?.
Why it exists: countries use time spent as a measurable proxy for where your economic life really is. A day count gives a clear threshold; the surrounding tests stop a long holiday from making a genuine non-resident taxable.
Counting the days
- Add up every day you were physically in Iowa between 1 January and 31 December.
- Days need not be continuous — several visits in the same year add together.
- Any day of presence generally counts, including arrival and departure days.
- The tally resets to zero on 1 January; it is not a rolling window. Reaching 184 days meets the threshold.
- The count alone does not decide this rule. It also depends on: Do you keep a home available to you in this state all year?.
The free calculator below counts this rule with the same engine the Dwelltime app ships.
Check it with the free tool
Examples
Example 1 — 109 days in the year
Stays: United States (IA) 2026-02-01 → 2026-05-20. Checked on 2026-12-31.
Result: Days in Iowa: 74 of 183 days left (109 used in Iowa).
Example 2 — 193 days in the year
Stays: United States (IA) 2026-01-15 → 2026-07-26. Checked on 2026-12-31.
Result: Days in Iowa: over the limit — 193 of 183 days, first exceeded 2026-07-17.
Example 3 — Days split across two calendar years
Stays: United States (IA) 2025-10-01 → 2025-12-31; United States (IA) 2026-01-01 → 2026-04-19. Checked on 2026-12-31.
Result: Days in Iowa: 74 of 183 days left (109 used in Iowa).
Exceptions & edge cases
- Other residency tests. Most countries also apply a domicile, home or centre-of-interests test; you can be resident under one of those with fewer days.
- Double-tax agreements. If two countries both claim you, the treaty tie-breaker (permanent home → centre of vital interests → habitual abode → nationality) decides.
- Split years. Arriving or leaving mid-year may be treated under special rules; the day count is only one input.
Common misconceptions
- "Under 183 days means I'm safe." False — other tests can apply, and the count is only one input.
- "It follows a rolling year." No — the tally resets on 1 January.
- "Arrival day doesn't count." Any part of a day inside is a day inside.
Frequently asked questions
Is the 183-day count per calendar year or rolling?
Calendar year (1 Jan – 31 Dec). The count resets on 1 January.
Do arrival and departure days count?
Yes — any part of a day counts as a day.
Where does this rule come from?
Iowa Department of Revenue: Individual income tax. The link is verified on every build; if it stops resolving the build fails.
This rule is tracked in 
Dwelltime
- Counts your days for this rule from the trips you record
- Shows the last safe day, or the days still needed, before you book
- Explains every counted day and every uncounted one
- Runs alongside your other visa, tax and residency rules
Sources
Related rules
- 🇺🇸US Visa Waiver (ESTA)Ninety days per admission, and the period cannot be extended while in the United States.
<=90 / VISIT - 🇺🇸US Substantial PresenceThis counter is the current year only. The real test weights the two prior years at one third and one sixth — use SubstantialPresenceRule for the full calculation.
<=182 / YEAR - 🇺🇸US FEIE physical presence330 full days abroad in any 12 consecutive months. Days in transit over international waters do not count as days abroad.
>=330 AWAY / 365 - 🇺🇸US naturalization presenceAt least half of the five-year statutory period — 913 days. A single absence of six months or more can also break continuity of residence, which this counter does not track.
>=913 / 1826 - 🇺🇸US green card — absenceAn absence of a year or more is treated as abandonment; six months or more invites questioning at the border. This counter is a conservative 180-day warning over a rolling year and is not the statutory test.
<=179 AWAY / 365 - 🇺🇸New York statutory residenceStatutory residence needs both a permanent home in New York and more than 183 days there. Days recorded only as "United States", with no state, are not counted — they are reported as unknown rather than guessed.
<=183 / YEAR - 🇺🇸New Jersey statutory residenceStatutory residence needs both a permanent home in New Jersey and more than 183 days there. Days recorded only as "United States", with no state, are not counted — they are reported as unknown rather than guessed.
<=183 / YEAR - 🇺🇸Massachusetts statutory residenceStatutory residence needs both a permanent home in Massachusetts and more than 183 days there. Days recorded only as "United States", with no state, are not counted — they are reported as unknown rather than guessed.
<=183 / YEAR
All 38 rules for United States →
For information only. This page is a plain-English summary of publicly available rules, not tax, legal or immigration advice. Rules change and depend on your personal circumstances — always confirm with the official source above and a qualified professional before acting.