Prop 13 rules, assessment limits, homestead exemptions, and county rate comparison.
California property tax is one of the most complex tax systems in the United States, governed primarily by Proposition 13 (1978) and, more recently, Proposition 19 (2021). Understanding how your home is assessed, when reassessment occurs, and what exemptions you qualify for can save you hundreds or thousands of dollars each year.
Proposition 13, approved by California voters in June 1978, fundamentally changed property taxation in the state. It has two core provisions:
This means a homeowner who bought their home in 1990 may pay dramatically less property tax than a neighbor who bought in 2025 — even though both homes are nearly identical and next door. This inequity is one of the most controversial aspects of California's property tax system.
Your home's assessed value is reset to current market value when:
California provides a base homestead exemption of $7,000 for all homeowners. Additionally, counties may offer an extraordinary relief exemption of up to $150,000 for seniors (age 65+), disabled persons, and victims of natural disasters, depending on county implementation and income qualifications.
Note: California's homestead exemption is relatively small compared to states like Florida ($50,000) or Texas ($40,000). The real tax protection in California comes from Prop 13's assessment cap, not the homestead exemption.
When you buy a home in California, you will receive a supplemental property tax bill in addition to the regular annual bill. This supplemental bill covers the difference between the previous owner's assessed value and the new assessed value for the remainder of the tax year.
For example: If you buy a home in October for $800,000, and the previous assessed value was $300,000, you will owe supplemental tax on the $500,000 difference for the portion of the year remaining (October through June). This bill is typically due within 30 days and can be several thousand dollars — be prepared!
If you believe your home's assessed value is higher than its fair market value, you have the right to appeal to your county's Assessment Appeals Board. The appeal process:
Successful appeals can reduce your assessed value for the current year and all future years until the home is sold or improved. This makes the appeal effort well worth it for many homeowners.
| County | Avg. Effective Rate | Avg. Annual Tax ($500K Home) |
|---|---|---|
| Los Angeles | ~1.16% | $5,800 |
| San Francisco | ~1.18% | $5,900 |
| San Diego | ~1.15% | $5,750 |
| Orange | ~1.05% | $5,250 |
| Alameda | ~1.25% | $6,250 |
| Sacramento | ~1.10% | $5,500 |
| Riverside | ~1.05% | $5,250 |
| San Bernardino | ~1.02% | $5,100 |
Use our Property Tax Calculator to estimate your specific California property tax bill based on your county, home value, and homestead exemption amount.