Quick overview

Form 1040‑NR is the primary U.S. tax return for individuals who are nonresident aliens for tax purposes but have U.S.‑source income. It determines U.S. tax liability, applies deductions available to nonresidents, and documents any treaty claims that reduce or exempt tax. For the IRS overview and the official form and instructions, see the IRS About Form 1040‑NR and the Form 1040‑NR PDF (irs.gov).

Who must file (common situations)

  • You were a nonresident alien (did not pass the green‑card or substantial‑presence test) and had U.S.‑source wages, salaries, tips or other income.
  • You had effectively connected income (ECI) from a U.S. trade or business.
  • You received fixed, determinable, annual, or periodic (FDAP) U.S. income subject to U.S. tax (for example, certain investment income reported on Form 1042‑S).
  • You are claiming a refund of overwithheld tax or claiming treaty benefits.

If you’re unsure whether your income is U.S.‑sourced or effectively connected, see our deeper guidance on when to use Form 1040‑NR (internal reference).

Key items to report and tax concepts

  • Wages and salaries (W‑2): report U.S. wage income unless exempted by a treaty.
  • Effectively connected income (ECI): income from a U.S. trade or business is generally taxed on net income after allowable deductions.
  • FDAP income: bank interest, dividends, rents and royalties often face different withholding rules and may be taxed at flat rates unless treaty relief applies.
  • Tax treaties: many countries have treaties that change how income is taxed or which deductions apply. If you claim treaty benefits, you normally must disclose the claim and cite the specific treaty article.

(For a plain‑language primer on treaties and cross‑border income, see our article on Understanding Tax Treaties: How They Affect Cross‑Border Income.)

Required documents

  • Social Security Number (SSN) or Individual Taxpayer Identification Number (ITIN). Apply with Form W‑7 if you don’t qualify for an SSN.
  • W‑2, 1042‑S, 1099s, or other income statements showing U.S.‑source income.
  • Records of allowable deductions (state and local tax withheld, business expenses if ECI, tuition/education documentation if applicable).
  • Form 8833 (Treaty-Based Return Position) if you claim treaty benefits that reduce tax liability.

Filing process and practical steps

  1. Confirm residency status (resident, nonresident, or dual‑status) using the green‑card and substantial‑presence tests.
  2. Gather income statements (W‑2, 1042‑S, 1099) and proof of withholding.
  3. Determine whether income is ECI or FDAP and whether a tax treaty applies.
  4. Complete Form 1040‑NR and any required schedules and statements (include Form 8833 for many treaty claims).
  5. Sign, date, and file. Historically, many 1040‑NR filers mailed the return; check the IRS page for the current e‑file status and mailing addresses (IRS: About Form 1040‑NR).

In my practice I often see students and visiting researchers overlook Form 8833 when claiming treaty benefits—document the treaty article and keep copies of employer letters or scholarship documentation.

Deadlines and extensions

Calendar‑year nonresident filers generally follow the same filing deadline as U.S. taxpayers (check the IRS for each tax year). If you can’t file on time, you can request an extension to file using Form 4868 in many cases, but extensions to pay are treated differently—file early or pay estimated taxes to avoid interest and penalties.

Common mistakes to avoid

  • Filing the regular Form 1040 instead of 1040‑NR.
  • Omitting U.S.‑source income (including small 1099 or 1042‑S items).
  • Claiming treaty benefits without required disclosures (Form 8833 or required statements).
  • Using the wrong ITIN or failing to apply for one before filing.
  • Forgetting to sign the return or including incomplete documentation.

Practical tips and professional strategies

  • Start early: ITIN applications (Form W‑7) can add weeks to your timeline.
  • Keep a copy of every foreign‑income statement and treaty paperwork.
  • If you operate a U.S. business or have self‑employment income, track expenses carefully to reduce ECI.
  • Consult a tax professional with nonresident experience when treaty positions, dual‑status, or business income are involved. In my experience, a short consult can prevent costly filing errors.

Interlinks (related FinHelp articles)

Authoritative sources and where to check for updates

Professional disclaimer

This article is educational and does not substitute for personalized tax advice. Rules about residency, treaty application, and filing procedures can change—consult a qualified tax advisor or the IRS website for decisions that affect your situation.