Does Wisconsin charge a demand charge on EV charging?

Both covered utilities do. We Energies bills about $12.28 per kilowatt-month at charging-site load factors after the tariff's hours-use mechanism is decomposed; MGE bills about $17.72 — or half that for sites that stay under 15% load factor, a provision the model discloses but deliberately does not assume.

How does Wisconsin's 3¢/kWh charging tax work?

The tax applies to electricity delivered into an EV battery by a Level 3 charger — dispensed energy, regardless of whether charging is free. Operators register with the Department of Revenue and file biannual returns. At default volumes it runs on the order of $34,000 a year, and the model carries it from year one.

Is Supercharger hardware taxed as property in Wisconsin?

Business personal property has been exempt statewide since the January 2024 assessment, so the model carries $0. One caveat is disclosed: property attached to leased land can be assessed as real property under a carve-out, and no EV-charger-specific guidance has been published.

ForgeAsset / Supercharger ROI / Wisconsin

Tesla Supercharger ROI in Wisconsin

Wisconsin pairs two structurally different utility designs with two statewide simplifications. Milwaukee sits in We Energies territory, whose commercial rate prices on-peak energy steeply and decomposes an hours-use mechanism into an energy adder plus a moderate demand charge at charging-site load factors. Madison is MGE country, where a three-window time-of-use rate carries a heavier demand figure — the model deliberately carries the un-discounted variant, because the tariff's low-load-factor relief lapses once a site's utilization crosses 15%. Statewide: a 3-cent-per-kWh tax on DC fast charging has been in force since January 2025, and business personal property tax was repealed from the 2024 assessment.

Model a Wisconsin site

What makes Wisconsin economics distinct

Milwaukee's hours-use mechanism, decomposed exactly

We Energies' Cg 3 rate reduces its on-peak demand charge as hours-use falls — arithmetic that decomposes exactly into a 12-cent on-peak energy adder plus about $12.28 per kilowatt-month at charging-site utilization. The decomposition is exact below the tariff's envelope and overstates the bill above it, so the model errs only toward caution. A rate case filed April 2026 re-bases the book in January 2027.

Madison's demand rate is carried un-discounted — deliberately

MGE's low-load-factor provision halves the on-peak demand rate for sites under 15% annual load factor, worth about $10,600 a month at model scale. The model carries the un-halved rate — about $17.72 per kilowatt-month — because the provision exits once load factor reaches 15% in two months of twelve, and a busy site crosses that line. The relief is real, automatic, and site-verifiable; carrying it by default would understate a successful site's bill.

The 3¢/kWh charging tax measures dispensed energy

Wisconsin's excise applies to electricity delivered into an EV battery by any Level 3 charger, whether or not the driver pays — about $34,000 a year at default volumes, carried from year one. It is measured on dispensed kWh, filed biannually, and paired with a partial offset: a resale exemption certificate can relieve sales tax on the portion of utility purchases transferred to drivers. The model keeps the full sales-tax fold as the conservative default.

No business personal property tax since 2024

Wisconsin repealed personal property tax from the January 2024 assessment, zeroing a line that runs tens of thousands of dollars a year in the heaviest covered states. One open reading is disclosed: fixtures on leased land can remain taxable as real property, and no EV-specific guidance exists either way.

Utilities and tariffs modeled in Wisconsin

Utility & tariff	Energy	Demand
We Energies Cg 3	6.7¢/kWh–23.8¢/kWh by time of day	$12.28/kW of monthly peak
MGE Cg-2	9.2¢/kWh–11.7¢/kWh by time of day	$17.72/kW of monthly peak

Rates are digit-verified against each utility's own filed sheets and update within two weeks of any revision. Full derivations are on the methodology page.

Wisconsin tax profile

Sales tax on hardware: 7.9%
Business personal property tax: none
Clean-fuels credit: no program
Per-kWh charging excise: 3.0¢/kWh (in force)

Wisconsin tax defaults applied: no clean-fuels credit program exists in Wisconsin (the LCFS revenue line is $0), and LLC costs use the $25 online annual report. Sales tax defaults to Milwaukee's 7.9% combined rate (Madison runs 5.5%) and business personal property has been exempt statewide since the 2024 assessment. Wisconsin's 3¢/kWh tax on electricity dispensed by DC fast chargers has been in force since January 2025 and is included from year one — on the order of $34,000 per year at default volumes. A resale exemption certificate can relieve sales tax on the portion of utility purchases transferred to drivers; the modeled rates keep the full tax as the conservative default.

Wisconsin programs and incentives

MGE Commercial EV Charging Allowance (Schedule CEVCA)

A make-ready allowance of $300 per kW of installed charging capacity ($200 at completion net of upgrade costs, $100 at the demand threshold), capped at a 5 MW pilot, for MGE commercial customers. Grant-shaped — an award enters the model through the grant inputs. The rider text carries no curtailment clause.

Wisconsin EV charging tax registration (DOR)

Operators of Level 3 chargers register with the Department of Revenue ($20 business tax registration) and file biannual EV-100 returns on the 3¢/kWh excise.

NEVI (federal, WisDOT-administered)

Federal corridor DC fast-charging funding administered by WisDOT in award rounds; Wisconsin's enabling legislation for per-kWh retail sales accompanied the 2024 program launch.

Wisconsin charging market

Wisconsin carries roughly 39 Supercharger stations along I-94, I-90, and I-43. We Energies serves Milwaukee, Racine, Kenosha, and the southeastern corridor; MGE serves Madison and its inner suburbs. The two territories do not touch — Alliant's Wisconsin Power & Light surrounds Madison, and municipal utilities like Sun Prairie and Cedarburg hold their own service areas; addresses there see a named-utility notice rather than a wrong auto-selection.

Wisconsin Supercharger ROI — questions

Does Wisconsin charge a demand charge on EV charging?: Both covered utilities do. We Energies bills about $12.28 per kilowatt-month at charging-site load factors after the tariff's hours-use mechanism is decomposed; MGE bills about $17.72 — or half that for sites that stay under 15% load factor, a provision the model discloses but deliberately does not assume.
How does Wisconsin's 3¢/kWh charging tax work?: The tax applies to electricity delivered into an EV battery by a Level 3 charger — dispensed energy, regardless of whether charging is free. Operators register with the Department of Revenue and file biannual returns. At default volumes it runs on the order of $34,000 a year, and the model carries it from year one.
Is Supercharger hardware taxed as property in Wisconsin?: Business personal property has been exempt statewide since the January 2024 assessment, so the model carries $0. One caveat is disclosed: property attached to leased land can be assessed as real property under a carve-out, and no EV-charger-specific guidance has been published.

Sources

Model a Tesla V4 Supercharger site in Wisconsin — payback, NPV, IRR, and a 15-year cash flow from your own inputs.

Run a Wisconsin scenario

Other states: California, North Carolina, Georgia, Oregon, Pennsylvania, Florida, Arizona, Texas, Virginia, Illinois, Michigan, Tennessee, Montana, Idaho, Kansas, Nebraska, North Dakota, South Dakota, Wyoming, New Mexico, Oklahoma, Alabama, Missouri, Iowa, Indiana, Louisiana, Nevada. Coverage spans twenty-eight states in total — see the full list.

ForgeAsset is software, not investment, tax, or legal advice — outputs are model estimates from your inputs, not guarantees. Rates and programs current as of research; verify current terms with each source before committing capital.