Property Tax Calculator
Annual and monthly property tax from home value, assessment ratio and rate.
Annual property tax
$3,850.00
on $350,000.00 assessed value
Monthly
$320.83
Assessed value
$350,000.00
Effective rate
1.1%
Mill rate
11
AI Breakdown & Smart Takeaway
Plain-English insight on your numbers
Get a personalized explanation of what these results mean — and how to improve them.
How the Property Tax Calculator works
The Property Tax Calculator estimates your annual and monthly property tax bill based on your home's market value, your local assessment ratio, and the applicable mill rate — making it an essential tool for homeowners, buyers budgeting for a new purchase, and real estate investors evaluating carrying costs.
The calculator works by replicating the exact process local governments use to determine your tax bill. It starts with your home's estimated market value — what the property would sell for in an open market — and applies your jurisdiction's assessment ratio to arrive at the assessed value. That assessed value is then multiplied by the mill rate (expressed as dollars of tax per $1,000 of assessed value) to produce your annual property tax. Dividing that figure by 12 gives you the monthly equivalent, which is particularly useful for budgeting or estimating mortgage escrow payments.
The assessment ratio is one of the most misunderstood variables in real estate tax calculations. Many people assume their home is taxed on its full market value, but most U.S. jurisdictions only tax a fraction of it. For example, a state might set an assessment ratio of 80%, meaning a $400,000 home is only assessed at $320,000. Some jurisdictions use 100% (full-value assessment), while others go as low as 10–20%. Always check your county assessor's website for the exact ratio in your area, because using the wrong figure can dramatically skew your estimate.
The mill rate — sometimes called the millage rate — is the lever local governments pull to fund schools, emergency services, infrastructure, and municipal operations. A mill equals $1 of tax for every $1,000 of assessed value, so a mill rate of 15 means you owe $15 per $1,000 assessed. Mill rates vary widely: urban areas with high service demands may exceed 30 mills, while rural or low-tax jurisdictions can fall under 10. Mill rates are also often composite figures, combining rates levied by the county, municipality, school district, and special taxing districts — so make sure you use the total combined rate when entering your figure.
A common mistake is conflating market value with assessed value and using the mill rate without understanding whether it's already expressed per $1,000 or as a percentage. Another pitfall is forgetting that most jurisdictions offer exemptions — homestead exemptions, senior exemptions, veteran exemptions — that reduce the taxable assessed value before the mill rate is applied. If you qualify for an exemption, subtract it from your assessed value before running the calculation to get a realistic number. Reassessments also happen periodically, meaning your tax bill can jump significantly after a home sale triggers a new appraisal at current market value.
Formula
Tax = (value × assessment ratio − exemptions) × tax rate
Pro tips
- Always verify your actual assessed value on your county assessor's website rather than estimating it — your official assessed value may differ significantly from your market value estimate and is what actually determines your bill.
- Factor in all exemptions you qualify for (homestead, senior, disability, veteran) before running the calculation; in many states these can reduce your taxable assessed value by $25,000 to $50,000 or more, meaningfully lowering your result.
- If you're evaluating a home purchase, use the calculator with the full purchase price as market value and the local assessment ratio — many jurisdictions will reassess at or near the sale price after a transaction, so don't rely on the seller's current tax bill as your future bill.
- Use the monthly output directly when estimating your total mortgage payment (PITI: principal, interest, taxes, insurance) to ensure you're budgeting accurately for escrow rather than being surprised by a large annual lump sum.
- Appeal your assessment if the calculated tax seems too high — if your assessed value exceeds what comparable homes in your neighborhood have sold for (adjusted by the assessment ratio), you likely have grounds for a formal reassessment appeal with your local taxing authority.
Key terms
- Market Value
- — The estimated price a property would fetch in a competitive, open real estate market between a willing buyer and seller.
- Assessed Value
- — The portion of a property's market value subject to taxation, calculated by multiplying the market value by the local assessment ratio.
- Assessment Ratio
- — The percentage of a property's market value that a taxing jurisdiction uses as the basis for calculating real estate tax, which varies by locality and can range from 10% to 100%.
- Mill Rate (Millage Rate)
- — The tax rate expressed as dollars of tax owed per $1,000 of assessed value, used by local governments to calculate annual property tax bills.
- Homestead Exemption
- — A legal reduction in a property's taxable assessed value available to owner-occupants, which lowers the property tax owed on a primary residence.
- Escrow
- — An account held by a mortgage lender into which a homeowner pays monthly property tax and insurance installments so the lender can make payments on the homeowner's behalf when they come due.
