Wisconsin Property Tax Calculator

How this calculator works

Wisconsin property tax is governed primarily by Wis. Stat. ch. 70 (the general property-tax chapter) and is constrained by Wis. Const. Art. VIII § 1 — the uniformity clause. The system has four structural features worth understanding before reading a tax bill:

1. Full-value assessment standard (§ 70.05). Local assessors must value property at full value, meaning fair market value.
2. Eight statutory property classes (§ 70.32), with agricultural land assessed at use value (§ 70.32(2r), § 70.114) and undeveloped / agricultural-forest land at 50% of full value (§ 70.32(4)).
3. Uniformity clause (Art. VIII § 1) blocks homestead exemptions and class-based ratio reductions for residential property.
4. Statewide credits on the net tax bill — the § 79.10 Lottery & Gaming Credit and the § 79.10(7m) School Levy Tax Credit — substitute for the homestead-style relief that other states deliver at the assessment level.

The math:

• market value × class-specific ratio = effective assessed value
• effective assessed value × combined mill rate = gross tax
• gross tax − Lottery & Gaming Credit − School Levy Credit = net tax bill

Everything else is determining the right class, the right mill rate, and which credits apply.

The full-value assessment standard — § 70.05

Wis. Stat. § 70.05(5)(a) requires local assessors to value property at full value — defined as fair market value. Practical assessment levels often diverge from market as values appreciate between revaluations, so the Department of Revenue computes an equalization ratio for each municipality and adjusts the assessed-value figure back to true cash value for state purposes: state-aid distribution, school-district funding, and inter-municipal tax apportionment.

Two values appear on a Wisconsin tax bill:

• Assessed value — the local assessor's figure for the specific parcel. The mill rate published on the bill is applied to this number.
• Equalized value — the Department of Revenue's adjustment of the assessed value to true cash value. Used for inter-municipal apportionment and tax-base comparisons.

For an individual residential bill, the assessed value is the figure that drives the tax. Equalized value matters most when comparing municipalities or computing the state-aid share of a school district's revenue.

The uniformity clause — Wis. Const. Art. VIII § 1

Wisconsin's constitution requires that "the rule of taxation shall be uniform" — one of the strictest uniformity provisions in the country. Wisconsin courts have read this as blocking the homestead exemptions, owner-occupied assessment ratios, and class-based ratio reductions that other states use to soften the residential tax bill:

• South Carolina — 4% owner-occupied ratio versus 6% for all other property
• Florida — $50,000 homestead exemption plus the Save Our Homes 3% annual appraisal cap
• Texas — $100,000 school homestead exemption plus Senior Citizen freeze
• Illinois (Cook) — 10% Class 2 residential ratio versus 25% Class 5 commercial

None of these are constitutionally permissible in Wisconsin without amending Art. VIII § 1. Wisconsin instead delivers residential relief through statewide credits applied to the net tax bill — the § 79.10 Lottery & Gaming Credit, the § 79.10(7m) School Levy Tax Credit, and the § 79.10(5m) First Dollar Credit. These are state-funded buy-downs of the local tax bill; they do not violate uniformity because every parcel of the same class receives the same statutory credit treatment.

The eight statutory property classes — § 70.32(2)

Wis. Stat. § 70.32(2) sorts all real property into eight classes:

| Class | Description | Assessment | | --- | --- | --- | | 1 | Residential | Full value (§ 70.05) | | 2 | Commercial | Full value | | 3 | Manufacturing | Full value (state-assessed by DOR under § 70.995) | | 4 | Agricultural | Use value (§ 70.32(2r), § 70.114) | | 5 | Undeveloped | 50% of full value (§ 70.32(4)) | | 5m | Agricultural-forest | 50% of full value (§ 70.32(4)) | | 6 | Productive forest | Full value | | 7 | Other | Full value |

The classification is determined by the local assessor based on the parcel's predominant use on January 1 of the tax year. A parcel with mixed uses can be split into multiple classes (so a 200-acre farm parcel with a residence might carry a small Class 1 residential portion and a larger Class 4 agricultural portion).

Agricultural use-value assessment — § 70.32(2r) and § 70.114

Class 4 agricultural land is assessed at use value — the value of the land based on its income-producing capacity in agricultural use, NOT at market value. The structure was added by 1995 Wis. Act 27 to reduce the tax burden on working farms facing development-driven appraisals.

Use values are published annually by the State Use-Value Council under § 73.03(2a), broken out by:

• Land grade: Grade 1 (best tillable), Grade 2 (medium), Grade 3 (marginal)
• County: each county has its own per-acre use-value figures
• Soil productivity index: refines the grade by parcel

Use values are typically a very small fraction of market value on tillable cropland near urban areas — often $100 to $300 per acre against market values of $5,000 to $15,000 per acre in the Madison and Milwaukee fringe counties. The calculator's planning estimate is 3% of market value, which is closer to the typical urban-fringe ratio; on prime cropland far from development pressure, the use-value-to-market ratio runs closer to 1:1.

Conversion penalty. Under § 74.485, removing land from agricultural use triggers a conversion charge equal to several years of the tax savings that the use-value assessment generated. The charge recaptures forgone tax when farmland is converted to a non-agricultural use — selling a farm to a developer means the conversion charge comes due at closing.

Undeveloped and agricultural-forest — § 70.32(4)

Class 5 (undeveloped) and Class 5m (agricultural-forest) are the only non-agricultural, non-residential classes that receive a statutory ratio reduction. Both are assessed at 50% of full value.

• Class 5 (undeveloped) — land in a marsh, lowland swamp, brush land, cutover, or other tracts not in productive use and not otherwise classified.
• Class 5m (agricultural-forest) — land producing or capable of producing commercial forest products and contiguous to a parcel classified as agricultural under the same ownership. The forestry component is tied to a working farm.

Bare forest land that is not contiguous to a Class 4 agricultural parcel is classified as Class 6 (productive forest) and assessed at full value — no 50% reduction. The Class 5m designation deliberately ties the forest-land tax benefit to working agriculture.

The Lottery and Gaming Credit — § 79.10

The Lottery & Gaming Credit is funded directly from Wisconsin Lottery proceeds and applied as a flat dollar credit against the net tax bill on every owner-occupied primary residence. The credit amount is set annually by the Department of Revenue based on lottery revenue; recent averages run $150 to $230 per eligible parcel, with $200 used in this calculator as a representative figure.

To qualify:

• The parcel must be the owner's primary residence on January 1 of the tax year.
• The owner must file a one-time claim on Form LC-100 with the municipal treasurer.

Once the claim is on file the credit carries forward each year until the parcel changes hands or the residency status changes. A large share of newly-eligible owners never file. The municipal treasurer will not enroll a parcel automatically; the credit shows up only after Form LC-100 is submitted. Owners who realize they have missed past years can file Form LC-300 for a retroactive claim back four years (§ 79.10(10)).

The School Levy Tax Credit — § 79.10(7m)

The School Levy Tax Credit is a separate state-funded credit distributed to municipalities in proportion to each municipality's school-tax levy and applied as a credit against each parcel's net tax bill. Effectively a state-funded buy-down of a portion of the school-tax component.

The School Levy Credit applies to ALL real property — there is no primary-residence test. Rental property, vacation property, and commercial parcels all receive it. The credit is the largest of the statewide property-tax credits in absolute dollars (over $1 billion annually statewide), reflecting the heavy school-funding share of the Wisconsin property tax.

The credit amount for any specific parcel is computed by the municipality based on its school levy and the parcel's equalized value; this calculator uses 8% of gross tax as a representative planning estimate for residential parcels.

Common combined mill rates by county

Combined municipal + county + school + technical college mill rates for 2024–2025 on residential primary residences. Rates are quoted as a percentage of full value (1% equals $10 per $1,000 of equalized value, the format on the Wisconsin tax bill):

| County | Combined rate | $350K home gross tax | $350K home net (with credits) | | --- | --- | --- | --- | | Waukesha | 1.70% | $5,950 | $5,274 | | Other / rural (typical) | 1.80% | $6,300 | $5,596 | | Brown (Green Bay) | 1.95% | $6,825 | $6,079 | | Eau Claire | 1.95% | $6,825 | $6,079 | | Outagamie (Appleton) | 2.00% | $7,000 | $6,240 | | Winnebago (Oshkosh) | 2.05% | $7,175 | $6,401 | | Dane (Madison) | 2.10% | $7,350 | $6,562 | | Rock (Janesville) | 2.15% | $7,525 | $6,723 | | Kenosha | 2.25% | $7,875 | $7,045 | | Racine | 2.30% | $8,050 | $7,206 | | Milwaukee | 2.45% | $8,575 | $7,689 |

Pull the binding combined rate for the specific parcel from the county real-property listing portal or the municipal treasurer. Combined rates can vary substantially even within a county — Milwaukee city, suburban Wauwatosa, and rural Franklin produce different combined rates within the same Milwaukee County rate column.

A worked example — $350,000 Madison primary residence

A $350,000 home in Madison (Dane County), owner-occupied primary residence, Lottery & Gaming Credit on file. Dane's typical combined rate is 2.10%.

• Effective assessed value: $350,000 (Class 1 residential, full value under § 70.05)
• Gross tax: $350,000 times 0.0210 equals $7,350
• Lottery & Gaming Credit (§ 79.10): $200
• School Levy Credit (§ 79.10(7m)): 8% of $7,350 equals $588
• Net tax: $7,350 minus $200 minus $588 equals $6,562
• Effective rate: 1.87% of market value

The credits move the bill from a 2.10% nominal rate to a 1.87% effective rate — a ~$788 reduction per year. The Lottery & Gaming Credit is the smaller of the two in absolute dollars but it is the only one that depends on the owner doing something (filing Form LC-100). The School Levy Credit lands on the bill automatically.

A worked example — same Madison home, owner never filed Form LC-100

Same $350,000 Madison home, but the owner has never filed the Lottery & Gaming Credit claim with the municipal treasurer.

• Gross tax: $7,350
• Lottery & Gaming Credit: $0 (no LC-100 on file)
• School Levy Credit: $588
• Net tax: $6,762

The unfiled LC-100 costs this owner $200 every year. The fix is filing Form LC-100 once with the municipal treasurer — the credit then carries forward. Owners who realize they have missed past years can file Form LC-300 for a retroactive claim back four years (§ 79.10(10)).

A worked example — same home, owner rents it out

Same $350,000 Madison home, now a rental — not the owner's primary residence.

• Gross tax: $7,350
• Lottery & Gaming Credit: $0 (rental, not primary residence)
• School Levy Credit: $588 (no primary-residence test)
• Net tax: $6,762

The owner forgoes the Lottery & Gaming Credit but still benefits from the School Levy Credit. The income-tax-side Homestead Credit (Wis. Stat. ch. 71 subch. VIII) is also unavailable on rental property — but that is an income-tax credit, not a property-tax credit, and follows the owner-occupant on Schedule H of the state income-tax return.

A worked example — $350,000 Milwaukee primary residence

A $350,000 home in Milwaukee, owner-occupied, LC-100 on file. Milwaukee's typical combined rate is 2.45% — the highest urban combined rate in Wisconsin.

• Gross tax: $350,000 times 0.0245 equals $8,575
• Lottery & Gaming Credit: $200
• School Levy Credit: 8% of $8,575 equals $686
• Net tax: $7,689
• Effective rate: 2.20% of market value

Milwaukee residential property pays roughly $1,127 more per year than the same home in Madison — driven entirely by the difference in combined mill rates (2.45% versus 2.10%). The state credits provide a similar absolute dollar reduction in both cities; the underlying mill-rate gap dominates the comparison.

A worked example — $500,000 working farm under use-value assessment

A $500,000 working farm in a rural Dane County township: 80 acres of cropland in continuous corn-soybean rotation, $35,000 average annual gross income, sound management. Parcel classified as Class 4 agricultural.

• Market value: $500,000
• Use value (planning estimate at 3%): $15,000 (the calculator's representative figure; binding figure published annually by the State Use-Value Council for the specific land grade and county)
• Effective assessed value: $15,000
• Gross tax: $15,000 times 0.0210 equals $315
• Lottery & Gaming Credit: $0 (not residential)
• School Levy Credit: 8% of $315 equals $25
• Net tax: $290
• Tax at full market value (no use-value): $500,000 times 0.0210 equals $10,500 (less ~$840 of school levy credit equals $9,660)

Use-value assessment reduces this farm's annual property tax by roughly $9,370 per year. The trade-off: removing the parcel from agricultural use triggers a conversion charge under § 74.485 equal to several years of the tax savings. Selling the farm to a developer means the conversion charge comes due at closing — typically tens of thousands of dollars for a fringe-suburban farm parcel.

A worked example — $200,000 undeveloped Class 5 parcel

A $200,000 undeveloped parcel in Dane County — wetland adjacent to a Class 4 farm but not in productive agricultural use itself. Classified as Class 5 undeveloped.

• Market value: $200,000
• Effective assessed value (50% under § 70.32(4)): $100,000
• Gross tax: $100,000 times 0.0210 equals $2,100
• Lottery & Gaming Credit: $0 (not residential)
• School Levy Credit: 8% of $2,100 equals $168
• Net tax: $1,932

The 50% ratio cuts the tax bill in half versus a Class 1 residential parcel at the same market value. Class 5m (agricultural-forest) on a parcel contiguous to a working farm receives the same 50% reduction.

Comparing Wisconsin to surrounding states

Effective property-tax rates on residential primary residences (net of statewide credits where applicable):

| State | Effective rate (typical) | Why | | --- | --- | --- | | Indiana | ~0.75% | 1% homestead cap on gross value | | Minnesota | ~1.05% | Classification + homestead market-value exclusion | | Michigan | ~1.30% | Headlee + Proposal A taxable-value cap | | Iowa | ~1.45% | Residential rollback (~54% of market) | | Wisconsin | ~1.40%–2.10% | Uniformity clause blocks ratios; credit-based softening | | Illinois | ~2.0%–2.5% | High combined millage; 10% Cook residential ratio |

Wisconsin sits above all its Midwest neighbors except Illinois. The state's uniformity-clause structure forecloses the classification ratios and caps that other Midwest states use — Michigan's Proposal A taxable-value cap holds annual appraisal growth to the lesser of 5% or inflation; Iowa's residential rollback cuts the assessment by roughly half; Indiana caps the residential bill at 1% of gross value. Wisconsin instead delivers relief through state-funded credits on the net bill — meaningful in dollar terms (~$800/year on a Madison residential primary residence) but smaller as a percentage softener than the structural caps in neighboring states.

When are Wisconsin property taxes due?

Wisconsin property taxes are billed in December for the prior tax year (a tax year runs January through December) and are typically payable in two installments — January 31 for the first half and July 31 for the second half. The municipal treasurer collects the first installment; the county treasurer collects the second installment.

The Open Book and Board of Review appeal process

To challenge an assessor's value, work through the statutory appeal calendar:

1. Open Book (§ 70.45) — informal review with the assessor, late spring before the formal Board of Review session. The assessor may correct obvious errors during Open Book without a formal appeal.
2. Board of Review (§ 70.47) — formal evidentiary hearing before the municipal Board of Review, late spring or early summer. Owner must file a written objection on Form PA-115A and appear with evidence (comparable sales, recent appraisal, professional opinion of value).
3. Wisconsin Tax Appeals Commission (Wis. Stat. ch. 73) — appeal from Board of Review decisions on questions of law or substantial evidence. Strict deadlines.
4. Circuit Court — judicial review under § 74.37 (excessive assessment claim, paid-under-protest action).

The Open Book and Board of Review sessions typically run for only a few days in each municipality. Miss the window and the assessment is locked in for the year. Watch the municipal newsletter or assessor's website for dates.

Common errors to avoid

• Confusing assessed value with equalized value. The mill rate on the bill applies to assessed value, not equalized value. Equalized value matters for inter-municipal comparisons and school-aid distribution but not for the individual tax bill.
• Forgetting to file Form LC-100. The Lottery & Gaming Credit requires a one-time claim with the municipal treasurer. Many newly-eligible owners never file and forgo $150 to $230 per year indefinitely.
• Confusing the Homestead Credit with the Lottery & Gaming Credit. Both target low-income owner-occupied populations, but the Homestead Credit (Wis. Stat. ch. 71 subch. VIII) is an income-tax credit filed on Schedule H of the state income-tax return — it has nothing to do with the municipal treasurer or the property-tax bill. The two credits stack — eligible owners can claim both.
• Treating Class 4 use value as a self-applied option. Use-value assessment under § 70.32(2r) is the assessor's classification call — there is no owner-side application. The assessor classifies based on predominant use on January 1; appeals go through Board of Review.
• Missing the § 74.485 conversion charge. Removing land from agricultural use triggers a charge equal to several years of forgone tax. Selling a farm to a developer means the conversion charge comes due at closing.
• Assuming Class 6 (productive forest) gets the 50% ratio. Only Class 5 (undeveloped) and Class 5m (agricultural-forest, contiguous to a working farm) get the 50% reduction under § 70.32(4). Bare forest not tied to agriculture is Class 6 at full value.
• Missing the Open Book / Board of Review window. The appeal calendar runs only a few days in late spring or early summer in each municipality. Miss it and the assessment is locked in for the year.

Tools, not advice. Confirm the binding municipal mill rate, the current statewide Lottery & Gaming Credit amount, and the parcel's statutory class with the municipal treasurer or county real-property listing office before relying on any result for planning purposes.