For income tax purposes, someone who isn’t a U.S. citizen is called an “alien.” Aliens are classified as nonresident aliens and resident aliens. See IRS Publication 519, U.S. Tax Guide for Aliens, to help determine whether you’re a nonresident or resident alien.

When making purchases in Idaho, you must pay sales tax and use tax, regardless of your citizenship unless you’re assigned to a foreign mission.

Income tax filing requirements

Nonresident aliens

If you’re a nonresident alien, you must file an Idaho return if your gross income from Idaho sources is more than $2,500.

If you file Form 1040NREZ or Form 1040NR with the Internal Revenue Service (IRS), you must use Idaho Form 43. Mark your residency status on the return as “Nonresident.”

You need to attach copies of these documents to your Idaho return when you file:

  • Federal Form 1040NR or 1040NR-EZ
  • All W-2 forms
  • All 1042-S forms
  • Form 8843, if filed with the IRS

Resident aliens

A resident alien is generally subject to Idaho tax in the same manner as a U.S. citizen. If you meet the Idaho filing requirements, you must file Idaho Form 40 or Form 43. Your Idaho residency status determines which form you file.


Claiming deductions and credits

Nonresident aliens can claim the same subtractions and credits available to other nonresidents. However, nonresidents don’t qualify for all the subtractions and credits available to Idaho residents. Among those allowed, the most commonly claimed by nonresident aliens include: the child and dependent care deduction, the health insurance premiums deduction, the credit for contributions to Idaho educational entities, and the credit for contributions to Idaho youth and rehabilitation facilities. You can find a description of these subtractions and credits in the instructions packet under instructions for Idaho Form 43 and the instructions for Form 39NR.

Claiming standard or itemized deductions

Most nonresident aliens can’t claim the standard deduction on their Idaho returns. However, students and business apprentices from India can claim the standard deduction according to their tax treaty.

Nonresident aliens can deduct certain itemized deductions on their Idaho returns. These deductions include charitable contributions to qualifying U.S. organizations, casualty and theft losses. Any state and local income taxes deducted on the federal return must be added back on the Idaho return.

Income tax exemptions

Idaho conforms to the Internal Revenue Code (IRC), which no longer allows personal exemptions.

U.S. treaty benefits

Nonresident aliens can claim tax treaty benefits on their Idaho tax return. Idaho honors all tax treaties recognized by the United States. Gross income amounts exempt by treaty are not included in the gross income filing requirement for Idaho. Refer to IRS Publication 901, U.S. Tax Treaties.

Example: Jose Garcia, a nonresident alien from Venezuela, earned $6,000 in wages while working in Idaho for a year. Since his wages exceed the $2,500 filing requirement, Mr. Garcia would normally have to file an Idaho return. However, the tax treaty with Venezuela exempts $5,000 of the wages, so only the remaining $1,000 is included in the gross income filing requirement. Mr. Garcia is not required to file an Idaho return.

Married nonresident aliens

Your Idaho tax filing status must be the same as the filing status on your federal return. For most taxpayers, the filing status is married, filing separate.

If you’re married to a U.S. citizen and choose to be treated for federal income tax purposes as a U.S. resident for the entire year, you’ll file a joint return. You must attach a copy of the statement that declares your choice to be treated as a U.S. resident to the Idaho return.

You must disregard community property laws if:

  • Both you and your spouse are nonresident aliens, or
  • One of you is a nonresident alien and the other is a U.S. citizen or resident and the nonresident alien spouse doesn’t choose to be treated as a U.S. resident.

Laws and rules