Your Madison assessment is likely too high if comparable homes in your neighborhood sold in 2025 for less than your assessed value. Mass appraisal models can be off by as much as 20% on individual homes, and errors in the assessor's records — wrong square footage, phantom features, missed condition issues — push that number further. Here's how to check yours and what to do if it's off.
Under Wisconsin law, your assessment is supposed to reflect your home's market value as of January 1, 2026, based on what comparable homes sold for during 2025. That's it. It's not what you paid for the house. It's not what Zillow says. It's the price a willing buyer would pay a willing seller in an arm's-length transaction, on that specific date.
So when you're checking whether your assessment is too high, you're really asking: could I have actually sold my house for this much on January 1, 2026?
The fastest sanity check is to find three to five homes that sold in your neighborhood in 2025 with characteristics similar to yours. You're looking for homes within about 20% of your square footage, similar age, similar lot, and ideally on your block or in your immediate area.
Take the sale prices and adjust mentally for differences. A 2,000 sq ft home with a finished basement that sold for $425,000 isn't a perfect comp for your 2,000 sq ft home with an unfinished basement — your home is worth less. A home with a brand new kitchen isn't a perfect comp for your home with a 1990s kitchen.
If your assessment is meaningfully higher than the adjusted comps suggest, that's a red flag.
This is a quick gut-check, not a precise tool, but it works. Take a few recent neighborhood sales and divide each sale price by the home's square footage. Then do the same for your assessment.
If your assessment comes out at $280/sq ft and recent sales in your neighborhood averaged $235/sq ft, your assessment is likely on the high side. The bigger the gap, the stronger your case for an objection.
The City of Madison Assessor uses mass appraisal — statistical models that estimate value across thousands of homes at once. Mass appraisal is efficient, but it can't see your house. It assumes "average condition" unless someone tells it otherwise.
Walk through your house and write down everything that's worse than average. Structural and major systems issues — old roof, original windows, aging siding, foundation cracks, basement moisture, outdated HVAC, knob-and-tube wiring, galvanized plumbing — materially reduce what a buyer would pay. Cosmetic and functional problems like a 1980s kitchen, original bathrooms, worn flooring, popcorn ceilings, or awkward floor plans get priced in by buyers but often missed by the assessor's model. Lot and exterior issues like drainage problems, no garage, busy street, problematic neighbors, easements, or odd lot shape can shave thousands off real market value.
If your house has significant issues that the city's data doesn't reflect, your assessment is almost certainly too high.
The City of Madison Assessor publishes a property record card for every parcel. Pull yours up and check:
Errors in this data are extremely common, and they all push your assessment up. If the city thinks your house has a finished basement and it doesn't, you're being assessed for value that doesn't exist.
In Madison, the combined property tax rate hovers around 2% of assessed value. That means every $10,000 you can knock off your assessment saves you roughly $200 a year. If you can demonstrate your home is overassessed by $30,000 — which is well within the 20% margin of error common in mass appraisal — you're saving $600 per year, every year, until the next reassessment cycle adjusts things.
That's real money for two minutes of effort.
You should file an objection if any of the following are true: comparable sales suggest your home is worth less than the assessment, your property record card has factual errors, your home has significant condition issues the city doesn't know about, or your assessment jumped much more than your neighbors' did this year.
If your home is in great condition, your square footage and features are accurate, and recent comparable sales support the assessor's number — you probably won't win. That's okay. Not every assessment is wrong.
We built a free tool using all 2,668 real 2025 sales from the City of Madison Assessor. It pulls the right comps for your home, walks you through condition factors, and tells you whether you have a real case — and if you do, it generates a ready-to-send objection email. Use our free tool at mycitymadeeasy.com to check your assessment and build your objection in 2 minutes. No signup, no cost.