Connecticut Property Tax Calculator
Connecticut doesn’t tax property the way New York City does. Every one of CT’s 169 towns assesses real property at exactly 70% of fair market value by state law, then applies its own local mill rate — a rate that varies enormously from town to town, since it’s set by each town’s own budget and grand list, not a statewide schedule. This calculator runs the real, statutory two-step formula so you get an accurate number for any CT town, once you know its current mill rate.
How Is Connecticut Property Tax Calculated?
Connecticut multiplies 70% of your home’s market value by your town’s mill rate, divided by 1,000. A mill is $1 of tax per $1,000 of assessed value. So a $600,000 home assessed at $420,000 (70%) in a town with a 20 mill rate owes $420,000 ÷ 1,000 × 20 = $8,400 a year — the mill rate is the only variable that changes between towns, since the 70% assessment ratio is fixed by state law (CGS §12-64) everywhere.
For reference: Greenwich’s mill rate for fiscal year 2025–26 is 12.041 — on the low end statewide, though actual bills there stay high because of elevated home values. Always confirm your specific town’s current mill rate with the town assessor, since rates are set annually and this figure will be out of date within the year.
Results
Enter a market value and mill rate below to see your property tax.
| Detailed Breakdown | |
|---|---|
| Market Value | $0 |
| Assessed Value (70% of market value) | $0 |
| Mill Rate Applied | 0 |
| Annual Property Tax | $0 |
| Monthly Equivalent | $0 |
Common Questions
A mill is $1 of tax for every $1,000 of assessed value. If your town’s mill rate is 20, you owe $20 in tax for every $1,000 of your property’s assessed value — not its full market value, since Connecticut only assesses at 70% of that.
Each town sets its own mill rate every year to fund its own budget, divided by its own grand list (the total assessed value of everything taxable in town). A town with a small grand list relative to its budget needs a higher mill rate to raise the same revenue as a town with a larger one — which is why rates can differ by a factor of five or more between neighboring towns.
Your town’s assessor’s office publishes the current mill rate, usually on the town’s official website, and it’s also compiled annually by the Connecticut Office of Policy and Management. Rates are set once a year and can change, so confirm the current figure rather than reusing last year’s.
Because the mill rate applies to 70% of your home’s value, not 100% — so your effective rate against full market value always works out to about 70% of what the mill rate alone would imply. A 20 mill rate translates to roughly a 1.4% effective rate on market value, not 2%.
Not necessarily. Towns with low home values often need higher mill rates to raise adequate tax revenue, while towns with very high home values, like several in lower Fairfield County, can fund their budgets with comparatively low mill rates. Compare the actual dollar tax bill, not just the mill rate, when weighing towns against each other.
