Data sources and methodology

Every figure links to a public source. This page explains which, and how they are combined.

Rates and medians

Effective rate = median real estate taxes paid ÷ median value of owner-occupied homes, both from the U.S. Census Bureau's American Community Survey 5-year estimates (tables B25103 and B25077) at county and place level. The 5-year series is used because it is available for every county, including small ones. We label the ACS vintage on each page.

Assessment rules, exemptions and calendars

State assessment ratios, homestead exemptions and appeal windows come from state departments of revenue and statute. County due dates, appeal deadlines and assessor contacts come from each county assessor or appraisal district's published calendar and are re-checked every year before bills go out.

What we do not do

• We do not estimate a parcel's exact bill. That requires the jurisdiction stack for the address, which only the county has.
• We do not model assessment caps for long-held homes; the estimator assumes a recent purchase.
• We do not use aggregator sites as sources.

Refresh cycle

ACS medians update annually in December. Calendars are verified each summer. Current data snapshot: 2026-09-20, tax year 2025.

Corrections

Report an error with the source document at contact. Verified corrections are published within a week.