File the homestead exemption
Most states offer a homestead exemption that removes a fixed amount from the taxable value of your primary residence, and many pair it with a cap on annual assessment increases. In most counties it must be filed once after purchase and is not applied automatically. It is free, it is permanent, and a surprising number of owners never do it.
Appealing an assessment
If comparable homes nearby are assessed lower, or the record lists the wrong square footage, bedroom count or condition, you can appeal. Deadlines are short — often 30 to 60 days after the notice arrives. Bring three to five genuinely comparable recent sales. Appeals succeed often enough that the hour is usually worth it on a large bill.
Assessment caps and the purchase reset
California's 2% cap, Florida's 3% Save Our Homes and Texas's 10% homestead cap all limit how fast assessed value can rise while you own. Critically, most reset to full market value when the property sells — which is why a new buyer's tax bill can be dramatically higher than the seller's, and why the listing's stated taxes can be badly misleading.
Escrow shortfalls
Your servicer estimates taxes and collects monthly. When the assessment rises, the escrow account falls short and you get both a lump-sum shortfall bill and a higher monthly payment. Budget for a payment increase in the second and third years of ownership, especially after a purchase that reset the assessment.
FAQ
How do I calculate my property tax?
Multiply the market value by the assessment ratio, subtract exemptions, then multiply by the millage rate and divide by 1,000. On a $420,000 home assessed at 100% with 11 mills, that is $4,620 a year.
What is a mill in property tax?
One dollar of tax per $1,000 of taxable value. A 22-mill rate is a 2.2% tax on taxable value — though because of assessment ratios, that may not equal 2.2% of market value.
Can I lower my property tax?
Yes, through exemptions you qualify for — homestead, senior, veteran, disability — and by appealing an assessment that is above comparable sales. Both routes are free to attempt.
Why did my property tax go up so much?
Usually a reassessment, a millage increase voted locally, or the loss of a cap after purchase. A new owner often pays far more than the previous owner on the same house because the assessment reset to the sale price.
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