Built and fact-checked by the DocNectar team — see our editorial standards
Key Features
Instant Calculation
Get accurate results in real time with our optimized algorithm.
Mobile Friendly
Fully responsive design. Works on all devices & screen sizes.
Privacy Focused
Your data stays on your device. We don't store any inputs.
100% Free
No hidden costs. This tool is completely free forever.
Property tax is one of the largest recurring costs of owning a home, yet it's calculated through a two-step process that surprises many first-time buyers: local governments in the US typically don't tax a home's full market value directly. Instead, most jurisdictions first apply an assessment ratio — a percentage that converts market value into a smaller "assessed value" — and only then apply the actual tax rate, commonly expressed as a mill rate (dollars of tax per $1,000 of assessed value), to that assessed figure. Skipping the assessment-ratio step and applying a mill rate straight to market value is one of the most common property-tax estimation errors, and it can throw an estimate off by a large margin, since assessment ratios vary widely — some jurisdictions assess near 100% of market value, while others assess at a much smaller fraction. This estimator walks through both steps explicitly using your local assessment ratio and mill rate, so you get a transparent, correctly-ordered estimate of your annual property tax bill rather than a rough guess.
How it works
Enter the home's market value, your local assessment ratio (as a percentage), and your local mill rate. The tool first computes assessed value as home value × assessment ratio ÷ 100, then computes the estimated annual tax as assessed value × mill rate ÷ 1000 — mirroring exactly how most US county and municipal assessors calculate a real property tax bill.
- Enter home market value.
- Enter assessment ratio (%).
- Enter mill rate (tax per $1,000 assessed value).
- Click Calculate to see your results.
Examples
A typical suburban home
A $300,000 home with an 80% assessment ratio and a mill rate of 25 has an assessed value of $240,000 (300,000 × 0.80) and an estimated annual tax of $6,000 (240,000 × 25 ÷ 1000).
A jurisdiction assessing at full market value
A $250,000 home with a 100% assessment ratio and a mill rate of 18 has an assessed value equal to the full market value, $250,000, and an estimated annual tax of $4,500 (250,000 × 18 ÷ 1000).
A lower assessment ratio area
A $400,000 home with a 40% assessment ratio and a mill rate of 30 has an assessed value of only $160,000 (400,000 × 0.40), producing an estimated annual tax of $4,800 — showing how a lower assessment ratio can offset a higher mill rate.
Who should use it
- Budgeting for property tax before buying a home.
- Sanity-checking a property tax bill against expected rates.
- Comparing estimated tax burden between two homes in different towns.
Industry applications
- Real estate
- Personal finance and homebuying
Advantages
- Separates the two real steps (assessment, then mill rate) so the estimate is transparent.
- Works for any assessment ratio, not just full-value jurisdictions.
- Helps compare tax burden across different jurisdictions.
Limitations
- An estimate only — actual bills may include additional special assessments or exemptions this tool doesn't model.
Common mistakes to avoid
- Applying the mill rate directly to market value instead of assessed value when the local assessment ratio isn't 100%.
- Using an outdated mill rate or assessment ratio, since local governments can adjust both periodically, often annually.
- Forgetting to account for available exemptions (like a homestead exemption) that would lower the actual bill below this base estimate.
Best practices
- Check your local county/municipal assessor's site for the exact current assessment ratio and mill rate — both vary significantly by location and change periodically.
- When comparing homes across different towns or counties, calculate the estimated tax for each rather than comparing mill rates alone, since assessment ratios can differ too.
- Budget property tax as an ongoing housing cost alongside mortgage principal, interest, and insurance, not just a one-time closing expense.
Tips
- Check for homestead exemptions or other local relief programs — they reduce assessed value before the mill rate is applied and aren't included in this base estimate.
- Recheck the mill rate annually, since local budgets and rates are often revised each year.