Wisconsin Income Tax: Rates, Rules, and How to File

The state of Wisconsin imposes an individual income tax on the earnings of its residents and on income generated within its borders by nonresidents. This tax serves as a primary source of revenue to fund public services, including education, transportation, healthcare, and public safety. The amount of tax an individual owes is determined by their income level, filing status, and eligibility for various deductions and credits.

Wisconsin Filing Requirements

Determining whether you need to file a Wisconsin income tax return depends on your residency status, gross income, and filing status.

Full-Year Residents

For individuals who are full-year residents of Wisconsin, the requirement to file a tax return is based on their gross income. For the 2025 tax year, single filers must file if their gross income is $13,560 or more. Married couples filing a joint return have a threshold of $25,190.

Those who are married but file separately must file if their gross income is $11,960 or more. Heads of household must file with a gross income of $13,560 or more.

Part-Year Residents and Nonresidents

Individuals who are part-year residents or nonresidents of Wisconsin must file a state return if they have a gross income of $2,000 or more from Wisconsin sources. This includes wages for services performed in Wisconsin and income from property located in the state. For married couples in this category, the filing threshold is a combined gross income of $2,000 or more from Wisconsin sources.

Calculating Your Wisconsin Taxable Income

The calculation of Wisconsin taxable income begins with your federal Adjusted Gross Income (AGI). Adjustments are then made to account for differences between federal and Wisconsin tax law. These involve adding certain income that is not taxed federally but is taxed by Wisconsin, and subtracting income that Wisconsin exempts from taxation.

Wisconsin requires specific additions to federal AGI, such as interest from municipal bonds issued by other states. Another addition is the amount of any state and local income taxes claimed as an itemized deduction on your federal return.

There are also several subtractions from federal AGI that can lower your Wisconsin taxable income. A primary subtraction is interest from U.S. government securities, such as Treasury bonds, which is exempt from state income tax. Another subtraction is available for up to $5,000 of retirement income for individuals who are 65 or older and meet certain income limitations. This subtraction is available to single filers with a federal AGI of less than $15,000 and married couples filing jointly with a federal AGI of less than $30,000.

After making adjustments, you must choose between taking the Wisconsin standard deduction or itemizing deductions. The standard deduction is a fixed amount based on your filing status. For 2025, the standard deduction is $13,560 for single filers, $25,190 for married couples filing jointly, and $17,510 for heads of household. You should itemize if your total eligible expenses exceed your standard deduction amount.

Wisconsin Tax Rates and Credits

Once your Wisconsin taxable income is determined, you calculate your tax liability using the state’s progressive tax rates. Wisconsin has four tax brackets with rates that increase as income rises. After calculating the tax, you may be able to reduce it by claiming various tax credits.

For the 2025 tax year, the rates are marginal, meaning each rate applies only to the income within its specific range.

The tax rates for single filers and heads of household are:

• 3.50% on income up to $14,680
• 4.40% on income between $14,681 and $29,370
• 5.30% on income between $29,371 and $323,390
• 7.65% on income over $323,390

For married couples filing jointly, the brackets are:

• 3.50% on income up to $19,580
• 4.40% on income between $19,581 and $39,160
• 5.30% on income between $39,161 and $431,190
• 7.65% on income over $431,190

The Homestead Credit is a refundable credit for low-income homeowners and renters. Eligibility is based on household income and the amount of property taxes or rent paid.

Another credit is the School Property Tax Credit, available to homeowners and renters. This credit is based on the property taxes or rent paid on a primary residence. For renters, a portion of rent is considered to be for property taxes.

Filing and Paying Your Wisconsin Taxes

The deadline for filing your Wisconsin income tax return is typically April 15th, aligning with the federal deadline. If you need more time, Wisconsin allows an automatic extension if you have filed for a federal extension. An extension to file is not an extension to pay, and you must pay any anticipated tax by the original due date to avoid penalties and interest.

You can file your Wisconsin tax return electronically or by mail. E-filing is the fastest method and can be done through tax preparation software or the Wisconsin Department of Revenue’s free online system. Paper forms can be downloaded from the Department of Revenue’s website and mailed to the address in the instructions.

If you have a balance due, you can pay online for free from your bank account through the Department of Revenue’s website. You can also pay by credit or debit card via a third-party vendor, which may charge a fee. If filing by mail, you can include a check or money order with your return.