Quick federal deadlines

  • U.S. citizens and resident aliens (including part‑year residents who file Form 1040): returns are normally due on Tax Day (typically April 15; may shift for weekends/holidays). If you live and work abroad, you usually get an automatic two‑month extension to June 15 (interest still accrues on unpaid tax). You can request an additional six‑month extension to October 15 by filing Form 4868; this extends filing time but not payment time. (See IRS Publication 519 and Form 4868 instructions.) IRS Pub. 519

  • Nonresident aliens (Form 1040‑NR): filing deadlines depend on circumstances. If you received wages subject to U.S. income tax withholding, your return is generally due the same date as residents (Tax Day). If you had no wages subject to withholding, a later deadline may apply. Always check the Form 1040‑NR instructions and the IRS pages for nonresident filing. About Form 1040‑NR

  • State deadlines: moving midyear often creates multistate filing obligations with their own due dates. Check the tax agency for each state where you lived or earned income.

Why deadlines differ

Residency status affects which returns you file and what income is taxable. A part‑year resident reports income for the portion of the year they were a resident (federal return is Form 1040); a nonresident reports U.S.‑source income on Form 1040‑NR. Different forms and withholding rules drive different due dates and extension rules. For state‑by‑state guidance see our article on How State Residency Is Determined for Part‑Year and Remote Workers and detailed state allocation guidance in Filing for Part‑Year Residents: Allocating Income Between States.

Practical steps and professional tips

  • Track your move dates and income sources. In my practice, clients who keep a simple move log and pay stubs make state allocations and federal filings much faster.
  • Pay estimated taxes or make a payment by the original due date to limit interest and penalties even if you file later via extension (Form 4868 for residents). For nonresidents, follow the 1040‑NR instructions and consult a tax advisor if unsure.
  • Use official IRS guidance for residency rules and treaty claims: Publication 519 and the Form 1040‑NR pages are primary sources. IRS Pub. 519 | About Form 1040‑NR

Common mistakes to avoid

  • Assuming a move erases filing obligations — you may owe taxes to both states for different parts of the year.
  • Missing that living abroad gives only an automatic two‑month extension, not a payment extension; interest applies.
  • Failing to check whether you must file 1040‑NR versus 1040 (a residency election can change the form and deadlines).

Short examples

  • Mid‑April move: If you move from State A to State B on July 1, you usually file a part‑year resident return in each state reporting income earned while a resident there and a federal Form 1040 for the full year.
  • International student: An exchange student who was a nonresident for the first half of the year and became a resident later may need to file 1040‑NR for the nonresident period and 1040 for the resident period or consult Pub. 519 about dual‑status returns.

Where to get official guidance

Professional disclaimer: This is educational information, not legal or tax advice. For an individualized filing strategy — especially if you have multistate income, treaty issues, or a dual‑status year — consult a qualified tax professional.

Internal resources

(Last checked against IRS guidance as of 2025.)