Wisconsin LLC Tax Filing: Forms & Rates (2026)

Q: How is a Wisconsin LLC taxed?

By default a Wisconsin LLC is a pass-through entity. A single-member LLC is disregarded and its income is reported on the owner's return, while a multi-member LLC files Form 3, the Wisconsin Partnership Return, and passes income through to the members. Members pay Wisconsin individual income tax at rates from 3.50% to 7.65%. An LLC can instead elect to be taxed as an S corporation or C corporation.

Q: What tax form does a Wisconsin LLC file?

It depends on classification. A single-member LLC reports on the owner's Wisconsin Form 1 (usually with a federal Schedule C). A multi-member LLC files Form 3. An LLC taxed as an S corporation files Form 5S, and an LLC taxed as a C corporation files Form 4 with the Wisconsin Department of Revenue.

Q: Does a Wisconsin LLC pay franchise tax?

A pass-through LLC does not pay a separate LLC franchise tax. Only an LLC that elects to be taxed as a C corporation pays Wisconsin's corporate income and franchise tax, which is a flat 7.9% on net income. Pass-through LLCs instead have their income taxed on the members' returns unless they make the entity-level election.

Q: When are Wisconsin LLC tax returns due?

For calendar-year filers, Form 3 (partnership) and Form 5S (S corporation) are due the 15th day of the third month, generally March 15. Individual Form 1 and C-corporation Form 4 are generally due April 15. Wisconsin follows the corresponding federal extension in most cases, but an extension to file is not an extension to pay.

Fact-checked by the LegalGlass editorial team against primary sources · Published Aug 6, 2026 · Last updated Aug 6, 2026

A Wisconsin LLC is taxed as a pass-through by default: a single-member LLC is disregarded and a multi-member LLC files Form 3 with the Department of Revenue, while members pay Wisconsin income tax at 3.50%–7.65%. An LLC can elect the flat 7.9% pass-through entity-level tax, or be taxed as an S corporation on Form 5S or a C corporation on Form 4.

Quick Answer

Default tax: Disregarded (single-member) or partnership (multi-member)
State income tax: 3.50%–7.65% on members' Wisconsin returns
Main return: Form 3 (partnership); Form 5S (S corp); Form 4 (C corp); Form 1 (owner)
Entity-level election: Optional 7.9% pass-through entity tax
Sales tax: 5% state (plus county), $20 Business Tax Registration
Agency: Wisconsin Department of Revenue (DOR)

How a Wisconsin LLC Is Taxed by Default

Wisconsin does not impose a distinct tax on the LLC form itself. Instead, a Wisconsin LLC is taxed according to how it is classified for federal income tax, and Wisconsin follows that federal classification. By default, a single-member LLC is a "disregarded entity": the IRS and the Wisconsin Department of Revenue (DOR) ignore the LLC as a separate taxpayer, and the owner reports the business's income and expenses on their own return, usually on a federal Schedule C that flows to Wisconsin Form 1. A multi-member LLC is treated as a partnership by default and files an informational return, Form 3 (the Wisconsin Partnership Return), passing each member's share of income out to them on a Schedule 3K-1.

In both default cases the LLC itself pays no separate Wisconsin income tax on its profits - the tax is paid by the members on their individual returns. This is what "pass-through" means. It is the same structure covered in the national business tax overview and in single-member LLC taxation. The classification an LLC starts with is not permanent: by filing the right federal election, an LLC can choose to be taxed as an S corporation or a C corporation instead, and Wisconsin honors that election automatically.

Federal Classification: Disregarded, Partnership, or Corporation

Because Wisconsin piggybacks on the federal choice, the first tax decision for a Wisconsin LLC is a federal one. An LLC may keep its default status, or file IRS Form 8832 to be taxed as a C corporation, or file IRS Form 2553 to be taxed as an S corporation. The entity-classification rules live in the federal regulations at 26 CFR § 301.7701-3. Each path changes which forms you file and how self-employment tax applies. See Form 2553 explained and Form 1120 vs 1120-S vs 1065 for the federal side.

The S-corporation election is the most common change for a profitable Wisconsin LLC, because it can reduce self-employment tax on the portion of profit taken as a distribution rather than salary. An S-corp must pay its owner-employees reasonable wages subject to payroll tax, and it files its own return. Weigh the payroll and compliance cost against the potential savings before electing - the analysis is in LLC vs S-corp tax and S-corp vs LLC. Whatever you choose federally, Wisconsin will tax the LLC the same way, using the matching state return.

Wisconsin Income Tax on LLC Members

Wisconsin has a graduated individual income tax. For 2026 the rates run from 3.50% at the bottom bracket to 7.65% at the top, with the top rate reaching taxable income above roughly $323,290 for single filers. Because a pass-through LLC's profit is taxed on the members' returns, these are the rates that most commonly apply to LLC income in Wisconsin. A member's total Wisconsin bill depends on their filing status, other income, and deductions - not on the LLC itself.

Wisconsin generally starts from federal adjusted gross income and then applies state additions and subtractions, so the federal treatment of the LLC's income carries into the Wisconsin calculation. Members who are Wisconsin residents pay tax on their entire distributive share; nonresident members pay Wisconsin tax on the share attributable to Wisconsin activity, and the LLC may need to file composite returns or withhold on nonresident members. The current bracket figures and thresholds are published on the DOR tax-rates page and should be confirmed there each year before filing, since brackets are indexed and can shift.

Wisconsin Tax Forms: Form 3, Form 5S, and Form 1

The Wisconsin return you file follows the LLC's classification. The table maps each classification to its Wisconsin form and the federal return it parallels.

LLC is taxed as	Wisconsin form	Federal return
Disregarded (single-member)	Form 1 (owner's return)	Schedule C / owner's 1040
Partnership (multi-member)	Form 3, Wisconsin Partnership Return	Form 1065
S corporation (elected)	Form 5S, Tax-Option (S) Corporation	Form 1120-S
C corporation (elected)	Form 4, Corporation Franchise or Income Tax	Form 1120

Form 3 and Form 5S are largely informational at the entity level unless the LLC makes the entity-level tax election described below: they report income and then pass it through to the owners on a Schedule 3K-1 (partnership) or 5K-1 (S corporation). The owners then report those amounts on their Wisconsin Form 1 (individuals) or their own business returns. Most Wisconsin business returns can be filed electronically through the DOR, and pass-through returns are generally required to be filed electronically. For the mechanics of filing across entity types, see how to file business taxes.

The Pass-Through Entity-Level Tax Election (7.9%)

Wisconsin lets a partnership or tax-option (S) corporation - including an LLC taxed either way - elect to pay Wisconsin income tax at the entity level at a flat 7.9% rate, rather than passing all the income out to be taxed on the owners' returns. This is the pass-through entity-level tax (often called the PTE tax or PTET), authorized under Wis. Stat. § 71.21(6) for partnerships and § 71.365(4m) for tax-option corporations. Partnerships make the election on Form 3 and S corporations on Form 5S; the election is made annually and requires the consent of owners holding more than 50% of the capital and profits interests.

The appeal of the election is federal: because the entity pays and deducts the state tax as a business expense, it effectively works around the $10,000 federal cap on the individual state and local tax (SALT) deduction. Members then take a credit or subtraction on their Wisconsin returns for the tax the entity paid, so the income is not taxed twice at the state level. The election is not automatically the best choice for every LLC - it interacts with credits, nonresident members, and estimated payments - so most owners run the numbers with a tax professional. See quarterly estimated taxes for how the entity's payments work if it elects in.

Corporate and Franchise Tax (If You Elect C-Corp)

If a Wisconsin LLC elects to be taxed as a C corporation, it leaves the pass-through world and pays Wisconsin's corporate income and franchise tax directly. That tax is a flat 7.9% on Wisconsin net income, reported on Form 4 (or Form 6 for a combined group). This is a genuine entity-level tax: the LLC pays 7.9% on its profit, and then any dividends distributed to members are taxed again on the members' individual returns - the classic "double taxation" of C corporations. Because of this, most small Wisconsin LLCs stay pass-through and do not elect C-corp status.

The label "franchise or income tax" reflects Wisconsin's structure: entities doing business in the state generally pay the franchise tax measured by net income, while the income tax version applies to certain entities not subject to the franchise tax. For an LLC, the practical point is that the pass-through default and the S-corp election both avoid this entity-level 7.9% on the LLC's own profit, while a C-corp election accepts it in exchange for corporate features. Compare the structures in LLC vs corporation and S-corp vs C-corp.

Wisconsin Sales and Use Tax

Separate from income tax, an LLC that sells taxable goods or certain services in Wisconsin must collect and remit sales and use tax. The Wisconsin state rate is 5%, and most counties add a 0.5% county tax, so the combined rate is commonly 5.5%. Before making taxable sales you must obtain a seller's permit by completing Business Tax Registration with the DOR; the registration fee is $20 and covers a two-year period, with a $10 renewal for each later period. The same registration covers employer withholding and other DOR permits.

Out-of-state sellers can trigger Wisconsin sales-tax obligations under economic nexus once their Wisconsin sales exceed $100,000 in the current or prior year, even without a physical location in the state. Sales-tax returns are filed on a schedule the DOR assigns (monthly, quarterly, or annually) based on volume. This obligation is independent of how the LLC is taxed for income - a disregarded single-member LLC still needs a seller's permit if it makes taxable retail sales. For what else applies to operating in the state, see business license in Wisconsin and the national business license guide.

Self-Employment Tax and Estimated Payments

Federal self-employment tax applies to the active business income of a default-taxed Wisconsin LLC. A single-member owner and general partners in a multi-member LLC generally pay 15.3% self-employment tax (Social Security and Medicare) on their net earnings, in addition to federal and Wisconsin income tax. This federal tax is one of the main reasons profitable LLCs consider the S-corporation election, which can convert part of the profit into a distribution not subject to self-employment tax - provided the owner takes reasonable wages first.

Because no employer withholds tax from an LLC owner's pass-through income, owners typically must make quarterly estimated payments to both the IRS and the Wisconsin DOR to avoid underpayment penalties. Wisconsin estimated payments for individuals are made with Form 1-ES on the usual quarterly schedule. An LLC that elects the entity-level PTE tax makes estimated payments at the entity level instead. Plan for these using quarterly estimated taxes and when business taxes are due.

Due Dates, Extensions, and Penalties

For calendar-year filers, Form 3 (partnership) and Form 5S (S corporation) are due the 15th day of the third month - generally March 15. Individual Form 1 and C-corporation Form 4 are generally due the 15th day of the fourth month, generally April 15. Wisconsin honors the corresponding federal extension for most returns, giving additional time to file, but an extension to file is never an extension to pay: tax owed is still due by the original date, and interest runs on unpaid amounts from that date.

Filing or paying late exposes the LLC and its members to interest and penalties assessed by the DOR, and continued nonfiling can lead to estimated assessments. Keeping the entity's income-tax returns, sales-tax filings, and the DFI annual report current is what keeps a Wisconsin LLC in good standing across both the tax and corporate systems. Because brackets, thresholds, and due dates can change, confirm the current figures on the DOR pages cited below before filing, and see Wisconsin LLC cost for the non-tax fees.

Frequently Asked Questions

How is a Wisconsin LLC taxed?

By default it is a pass-through: a single-member LLC is disregarded and reports on the owner's Form 1, while a multi-member LLC files Form 3 and passes income to the members, who pay Wisconsin income tax at 3.50%–7.65%. An LLC can instead elect S-corp or C-corp treatment.

What tax form does a Wisconsin LLC file?

A single-member LLC reports on the owner's Form 1 (with a federal Schedule C). A multi-member LLC files Form 3, an S-corp LLC files Form 5S, and a C-corp LLC files Form 4 with the DOR.

Does Wisconsin have a pass-through entity tax election?

Yes. A partnership or tax-option (S) corporation may elect to pay a flat 7.9% Wisconsin tax at the entity level, on Form 3 or Form 5S. Owners holding more than 50% of capital and profits must consent, and the election is annual.

Does a Wisconsin LLC pay franchise tax?

Only if it elects C-corporation treatment, in which case it pays the 7.9% corporate income and franchise tax. A pass-through LLC pays no separate LLC franchise tax; its income is taxed on the members' returns instead.

When are Wisconsin LLC tax returns due?

For calendar-year filers, Form 3 and Form 5S are generally due March 15, and Form 1 and Form 4 are generally due April 15. An extension to file is not an extension to pay.

Sources

Wisconsin Dept. of Revenue - Tax Rates (individual 3.50%–7.65%; corporate franchise/income 7.9%).
Wisconsin Dept. of Revenue - Pass-Through Entity-Level Tax: General Election Questions (7.9% entity-level election; >50% owner consent; annual).
Wisconsin Dept. of Revenue - Partnerships (Form 3, Wisconsin Partnership Return).
Wisconsin Dept. of Revenue - Corporations (Form 4; Form 5S tax-option S corporation).
Wisconsin Dept. of Revenue - Business Tax Registration ($20 initial, $10 renewal, seller's permit).
Wisconsin Dept. of Revenue - Sales and Use Tax (5% state rate; county 0.5%).
Wisconsin Dept. of Revenue - Individuals (Form 1; Form 1-ES estimated payments).
Wisconsin Statutes - § 71.21, Partnership pass-through entity-level tax election.
Wisconsin Statutes - § 71.365, Tax-option corporation entity-level tax.
Wisconsin Statutes - Chapter 71, Income and Franchise Taxes.
IRS - Limited Liability Company (LLC) (default federal classification).
IRS - S Corporations (Form 2553 election; Form 1120-S).
Legal Information Institute (Cornell) - 26 CFR § 301.7701-3 (entity classification election).

LegalGlass provides general information for educational purposes and is not a law firm or a substitute for advice from a licensed attorney or tax professional. Laws, rates, brackets, and due dates change; verify current requirements with the Wisconsin Department of Revenue and the IRS before acting.