County Tax Calc
Estimates only — for informational purposes. California's base rate is set by Proposition 13, but total rates vary by county, city, and voter-approved bonds. Verify your assessed value and rate with your county assessor or the California Board of Equalization.

California Property Tax Calculator

Estimate your California property taxes. Proposition 13 caps assessment increases at 2%/year after a change in ownership. Enter your county-assessed value and your total bill rate (1% base + any local additions).

The Formula

Annual Tax = Taxable Assessed Value × (Mill Rate ÷ 1,000)

Assessed Value = Market Value × Assessment Ratio (state-specific — see note below)
Mill Rate: 1 mill = $1 per $1,000 of assessed value. Enter your actual rate from your county tax bill.

California Property Tax Inputs

Assessment ratio note: California assesses at 100% of fair market value at the time of the most recent change in ownership or new construction (Proposition 13). After that, the assessed value may increase by no more than 2% per year. Source: California BOE, boe.ca.gov (as of June 2026).

$
%

Pre-filled with California's common ratio. Verify on your tax bill.

mills

Enter your actual combined mill rate. The pre-filled value is illustrative only.

$

Dollar reduction from assessed value. Check with your county assessor.

Annual Tax
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Monthly (escrow est.)
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Assessed Value
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Effective Rate
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California Property Tax — Key Facts

  • Proposition 13 base rate: 1% of assessed value statewide. Total bills are higher due to voter-approved bonds. Source: California BOE (June 2026).
  • Annual value cap: Assessed value may increase no more than 2% per year (or CPI, whichever is lower) until a change in ownership triggers reassessment to current market value.
  • Homeowner's Exemption: A $7,000 reduction in assessed value is available to homeowners who occupy their home as their principal residence. File with your county assessor.
  • Property Tax Bill: Billed in two installments — first due November 1 (delinquent December 10), second due February 1 (delinquent April 10).
  • Find your rate: Contact your county assessor. The BOE oversees all 58 county assessors — boe.ca.gov.

Source: California State Board of Equalization — boe.ca.gov/proptaxes/proptax.htm (verified June 2026).

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Frequently Asked Questions

How does California's Proposition 13 affect property taxes?

Proposition 13 (1978) limits the annual increase in assessed value to no more than 2% per year (or the rate of inflation, whichever is lower), until a change in ownership or new construction, which triggers a reassessment to current market value. The base tax rate is 1% of assessed value plus voter-approved debt service.

What assessment ratio does California use?

California assesses at 100% of fair market value at the time of the most recent change in ownership or new construction. The BOE oversees compliance by the 58 county assessors. Source: California BOE, boe.ca.gov/proptaxes/proptax.htm (June 2026).

What is California's base property tax rate?

Proposition 13 established a base rate of 1% of assessed value statewide. Individual bills are typically higher because they include voter-approved bond and special assessment add-ons. Enter your total rate from your county tax bill for an accurate estimate.

Where can I find my California property tax information?

Contact your county assessor's office. The California BOE oversees all 58 county assessors — visit boe.ca.gov or your county assessor's website for your assessed value and tax rate information.