Property tax calculator guide
Property tax is generally based on taxable assessed value, which may differ from market value. Assessment ratios, exemptions, millage rates, levies, caps, and reassessment schedules vary by jurisdiction.
This calculator converts the entered local rules into an estimate and projects a simple annual growth scenario.
How to use the property tax calculator
- Enter market value: Use a reasonable current property value.
- Enter assessment ratio: Use the local rule or 100% where applicable.
- Subtract eligible exemptions: Include only approved or likely exemptions.
- Enter combined rate: Combine applicable local taxing authorities.
Formula and variables
The calculator applies the entered housing, financing, and cost assumptions consistently.
Tax = max(assessed value − exemptions, 0) × tax rate- Assessment ratio — Taxable assessment percentage
- Share of market value used as assessed value.
- Exemption — Eligible value reduction
- Amount removed before applying the rate.
Worked example: exemption lowers taxable value
A $350,000 home is assessed at 100% with a $50,000 exemption.
- Combined rate
- 2%
- Taxable value is $300,000.
- Multiply by 2%.
Result: Estimated annual tax is $6,000
The actual bill controls.
Understanding your results
Annual tax
Modeled liability before discounts, penalties, or special assessments.
Monthly escrow
Annual estimate divided by 12.
Assumptions
- Entered combined rate applies to taxable value.
- Exemptions are valid.
Limitations
- Special assessments, caps, and timing are excluded.
- Projection is not a government forecast.
Common mistakes
- Applying the rate to market value when assessed value differs.
- Confusing mills with percent.
- Assuming an exemption is automatic.
Practical use cases
Compare housing scenarios
Change one assumption at a time to identify the factors driving the result.
Plan before committing
Use estimates to prepare questions and budgets, not as a guarantee.
Planning and decision guide
Verify units
One mill equals $1 per $1,000 of taxable value, or 0.1%.
Appeal deadlines matter
Review the assessment notice and local evidence requirements promptly.
Escrow can lag tax changes
Mortgage escrow adjustments may occur after a bill changes.
Frequently asked questions
Is assessed value the same as market value?
Not always; local assessment rules determine taxable assessment.
How do I convert mills to percent?
Divide mills by 10; 20 mills equals 2%.
Does the calculator include exemptions?
Yes, as a total reduction entered by the user.
Why did my escrow payment change?
Taxes, insurance, shortages, and servicer analyses can change escrow.
Sources and review
- Property taxes and your mortgage — Consumer Financial Protection Bureau. Accessed 2026-07-10.
Reviewed 2026-07-10.