Wisconsin state income tax — ITIN filer guide

Wisconsin uses a graduated income tax from 3.5% to 7.65% (tax year 2025), administered by the Wisconsin Department of Revenue. This guide covers who must file, how filing with an ITIN works, whether the state EITC applies to you, and when refunds arrive.

GRADUATED: 3.5% – 7.65% · 4 brackets

  • State return form: Form 1
  • Deadline (tax year 2025): April 15, 2027
  • Who must file: TY2025: gross income $13,930+ (single under 65) or $25,890+ (MFJ both under 65); nonresidents/part-year residents with $2,000+ of Wisconsin-source income
  • State sales tax: 5%

Wisconsin refund timing

  • E-filed returns: Most e-filed refunds issued in less than 3 weeks; fraud and error safeguards can delay some refunds up to 12 weeks
  • Paper returns: Paper returns take roughly 6-8+ weeks; allow up to 12 weeks from the date filed
  • Check your Wisconsin refund status

State tax agency

  • Wisconsin Department of Revenue — revenue.wi.gov
  • Free filing option: WisTax — the state's own free, secure e-file system (available for 2025 returns from February 2026) for eligible full-year residents with WI ID and prior filing history; others use vendor software or paper

Facts verified 2026-06-11 against official state sources (primary source). Figures refresh with every dataset review.

Filing with an ITIN

Your ITIN is fully accepted on the Wisconsin state return — states accept the IRS-issued taxpayer number, the same one you use federally. The flow is always the same:

  1. Complete your federal return first (Form 1040 + ITIN)
  2. Transfer your federal figures to Form 1
  3. Apply state-specific deductions and credits
  4. E-file — WisTax — the state’s own free, secure e-file system (available for 2025 returns from February 2026) for eligible full-year residents with WI ID and prior filing history; others use vendor software or paper
  5. Or visit a VITA site for free in-person preparation

Wisconsin state EITC — do ITIN filers qualify?

The federal EITC requires valid SSNs for you, your spouse, and qualifying children — ITIN filers can never claim it. What varies is the STATE credit:

Wisconsin Earned Income Credit — 4% (1 child), 11% (2 children), 34% (3+ children); no credit for filers without qualifying children of the federal EITC (refundable)

✗ SSN required (not available to ITIN filers)

Computed as a percentage of the federal EITC actually claimed, so the federal SSN requirement carries over — ITIN filers cannot claim it. Wisconsin is not among the states extending EITC to ITIN filers.

See how all 52 jurisdictions compare on the state tax hub and which tax credits ITIN filers can claim.

Last verified: 2026-06-11. Primary source: Wisconsin Department of Revenue.

General procedural information for educational purposes. Not legal or tax advice. State tax rates change frequently — verify current figures with the state agency before filing. For case-specific guidance, consult a tax professional, enrolled agent, or CPA.