Idaho Residency

No. Idaho's statutory residency threshold is 270 days, not 183, and any part of a calendar day with Idaho presence counts as a full day toward that total under Idaho Code §63-3013(1)(b). You're a statutory resident if you maintain a place of abode in Idaho for the entire year and hit that 270-day aggregate, independent of domicile.

Not necessarily, if you qualify for Idaho's 445-day absence exception: being out of Idaho for at least 445 days within a 15-month period lets a domiciled Idahoan be treated as a nonresident. But the exception doesn't apply if your spouse or minor children keep living in your Idaho home more than 60 days a year, or if you claim Idaho as your federal tax home for away-from-home expenses.

Up to 270 days in the aggregate during the year, since Idaho's statutory residency test kicks in above that threshold for anyone maintaining an Idaho place of abode. But Idaho counts any part of a day as a full day, so short visits add up faster than in states with a majority-of-day rule.

Form 43, the Idaho Part-Year Resident & Nonresident Income Tax Return. If you and your spouse have different residency statuses and file a joint federal return, you must also file a joint Idaho Form 43, with each spouse's status listed separately.

No. Idaho fully exempts Social Security benefits from state income tax. Other retirement income like pensions, 401(k), and IRA withdrawals is generally taxed at the flat 5.30% rate, though a separate Retirement Benefits Deduction covers qualifying public-system pensions for taxpayers 65 and older or 62 and disabled.

Idaho taxes capital gains as ordinary income but allows a 60% deduction on net gains from qualifying Idaho property, generally real property held at least 12 months, claimed on Form CG. The deduction is specific to Idaho property; gains on out-of-state real estate or most stocks and financial assets don't qualify.

You can have separate residences and separate domiciles. If you file a joint federal return, Idaho requires a joint Idaho Form 43 with each spouse's residency status listed separately, resident versus nonresident. Because Idaho is a community property state, if the other spouse lives in a community property state too, such as Washington, each spouse generally reports half of the combined community income on the Idaho return, not just their own earnings.

No. Idaho has no formal declaration-of-domicile filing. Domicile is shown through conduct: where your family lives, where you do business, how you actually spend your time, and whether you've given up your Idaho driver's license or Homeowner's Exemption.

Both are generally due within 90 days of becoming an Idaho resident, one of the more generous new-resident windows among Mountain West states.

No documented large-scale residency-audit program has been published for Idaho, and it isn't named among the states most commonly flagged as aggressive on residency. The state's real trap for residents is procedural: the 445-day absence exception has hard disqualifiers, most importantly a spouse or minor children staying in the Idaho home, that catch people who assume a long absence alone changes their status.