California Property Tax Guide: Prop 13, Rates by County and a Worked Bill

How California property tax works

California property tax is a tax on the assessed value of your home, set once when you buy and then allowed to rise by no more than 2% a year. The rate starts at 1% of that assessed value, and voter-approved bonds and local charges are added on top. Across all property, the Board of Equalization (BOE) reports average rates for 2024-25 from 1.000% in Modoc and Sierra counties to 1.248% in Kern County.

Four offices handle your bill. The county assessor sets the assessed value. The county auditor applies the tax rates and allocates the money. The county tax collector mails the bill and collects it. The BOE writes the rules and forms that every county follows. Property tax raised about $100 billion for local government in 2024-25, and the BOE reports that 53.5 cents of each dollar went to schools, 14.1 cents to counties, 12.2 cents to cities and 20.2 cents to other districts.

Prop 13 and the rules behind every California property tax bill

Prop 13's 1% general tax rate limit

Voters approved Proposition 13 on June 6, 1978. It limits the general property tax to 1% of a property's taxable value, plus the rate needed to repay voter-approved debt. That added debt can be bonds approved before July 1, 1978, bonds for buying or improving real property approved by two-thirds of voters since then, and school facility bonds approved by 55% of voters (allowed since January 1, 2001).

Base year value: what you paid sets your assessment

Prop 13 rolled most assessments back to 1975 market values. Since then a property is reassessed to market value only when it changes ownership or new construction is completed. That market value is the base year value. A home bought in 2026 for $800,000 gets a base year value of about $800,000, while the identical house next door bought in 2006 may be assessed at a fraction of that.

The 2% annual cap on assessed value increases

Each January 1 the assessor adjusts the prior year's value for inflation, by no more than 2%. The adjusted figure is called the factored base year value. Your taxable value is the lower of the factored base year value and the property's market value on January 1.

Change in ownership and new construction reassessments

A sale, most transfers of title and many transfers of control trigger reassessment to market value as of the transfer date. So does completed new construction, such as an addition or a major rehabilitation. Some transfers are excluded, such as qualifying parent-child transfers under Prop 19; ask the assessor before you retitle a home. Active solar energy systems are excluded from new construction until the property changes ownership; the BOE says that exclusion is scheduled to end on January 1, 2027, so check its status before you install.

Prop 8 decline-in-value reductions

If your home's market value on January 1 falls below its factored base year value, the assessor must enroll the lower market value. This is a Proposition 8, or decline-in-value, assessment. While a property is in decline-in-value status its assessed value can rise by more than 2% a year as the market recovers, but it can never go above the factored base year value unless the home sells or is improved.

Tax rate areas: why neighbors pay different rates

Every part of the state is mapped into a tax rate area, a zone with a unique mix of taxing agencies such as a city, school district, water district and community college district. Two homes in the same county can sit in different tax rate areas and pay different total rates because they repay different voter-approved bonds. Your tax rate area number is printed on your bill.

California property tax rate by county

The table shows the BOE's 2024-25 average property tax rate for each county with a California Housing Prices county guide, alongside Zillow's typical home value for September 2026. The last column multiplies the two to show roughly what a buyer paying that price might owe in a year, before the homeowners' exemption, special taxes and fixed charges. It is an illustration: average rates blend all property in the county, and your bill depends on your tax rate area, any Mello-Roos district and the price you pay.

Kern County's average rate is the highest of these at 1.248%, but its typical home value of $360,205 keeps the illustrative bill near $4,495. Santa Clara County's 1.193% on a $1,562,682 typical value gives about $18,643. The full list of all 58 counties is in the BOE's 2024-25 annual report, and county home values are on the California data page.

Worked example: a California property tax bill under Prop 13

This example uses round numbers to show the math. Your county's rates and charges will differ.

Year one: the 1% levy, bonds, exemption and direct charges

You buy a home for $800,000 and live in it. Your tax rate area has 0.15% in voter-approved bonds, for a total rate of 1.15%. Your bill also lists $400 in fixed direct charges, such as a lighting district or sewer fee.

The bill is paid in two installments of $4,759.75. Without the homeowners' exemption the value-based part would be $800,000 x 1.15% = $9,200 instead of $9,119.50, so the exemption saves $80.50 at this 1.15% rate.

Year two: the 2% cap on the assessed value

If the inflation factor is the full 2%, the assessed value becomes $800,000 x 1.02 = $816,000. Less the $7,000 exemption gives $809,000. At 1.15% the ad valorem tax is $9,303.50, plus $400 in charges, for $9,703.50. Bond rates can change each year, so the second part can move up or down even when the value rises only 2%.

Ten years later: how Prop 13 caps the growth

At the maximum 2% a year, the assessed value after 10 years is $800,000 x 1.02 raised to the tenth power, or about $975,196. If the market value has grown faster, the tax still follows the capped figure. If the market has fallen below it, a Prop 8 reduction applies instead.

California property tax exemptions for homeowners

Homeowners' exemption: $7,000 off the assessed value

The California Constitution requires a $7,000 reduction in taxable value for an owner-occupied principal residence. The BOE says it typically cuts a bill by about $70. The home must be your principal residence on January 1, rentals and vacation homes do not qualify, and you file once on form BOE-266 with the county assessor. File by February 15 for the full exemption; claims filed by December 10 get 80% of it.

Disabled veterans' exemption

Qualifying disabled veterans, or unmarried surviving spouses of deceased disabled veterans, can exempt $100,000 of their principal residence's value, or $150,000 if household income is under the income limit ($40,000 in the base law). Both amounts and the income limit are adjusted every year for inflation, so ask the assessor for the current figures. The basic exemption is a one-time filing; the higher one needs an annual filing.

Parent-child transfers and Prop 19 portability

Proposition 19 lets owners who are 55 or older, severely disabled or disaster victims move their assessed value to a replacement home anywhere in California up to three times, and it narrowed the parent-child exclusion to a family home the child moves into, with a value cap. Our Prop 19 guide has the rules, forms, deadlines and worked examples.

Supplemental property tax bills after you buy

When you buy, the county does not wait for the next January 1 to reassess. It issues a supplemental assessment for the difference between your new base year value and the old taxable value, prorated over the rest of the fiscal year (July 1 to June 30). If you buy between January 1 and May 31, you get two supplemental assessments: one for the rest of the current fiscal year and one for the whole next year. If the new value is lower, you get a refund.

Supplemental bill example

The seller's taxable value was $400,000 and you buy for $800,000 on October 1. The supplemental assessment is $400,000. With about nine months left in the fiscal year, the supplemental tax at 1.15% is roughly $400,000 x 1.15% x 0.75 = $3,450. Counties use their own proration factors, so the exact figure will differ.

Who pays the supplemental bill

Supplemental bills go to the owner, not the lender, so they are not paid from an impound account. If the bill is mailed between July 1 and October 31, it is due on the regular December 10 and April 10 dates. If it is mailed between November 1 and June 30, the first installment is delinquent on the last day of the month after the bill is mailed.

Mello-Roos and other special taxes on the bill

Below the 1% levy and bonds, your bill may list special taxes and assessments. The most common in newer communities is the Mello-Roos special tax, levied by a community facilities district to repay bonds for roads, schools, parks and other public facilities. Most districts set it by a formula, such as home size, rather than by assessed value, and it is charged on top of Prop 13's 1% rate. Read our Mello-Roos guide to look one up and see how it affects what you can afford. Older neighborhoods may carry 1915 Act assessments, which work in a similar way.

California property tax due dates and penalties

Secured property tax installment dates

Counties mail the annual secured bill by November 1. The first installment is due November 1 and becomes delinquent after December 10. The second is due February 1 and becomes delinquent after April 10.

Late payment penalties and tax default

A late installment carries a 10% penalty. If taxes stay unpaid after the notice of impending default, the property becomes tax-defaulted and redemption penalties of 1.5% a month are added. If the taxes, penalties and costs are not paid within five years, the county may sell the property at public auction.

Key dates in the California property tax year

• January 1: lien date; ownership and value are fixed for the coming fiscal year.
• February 15: deadline for the full homeowners' exemption.
• July 1: assessor completes the assessment roll.
• July 2 to September 15 or November 30: regular appeal filing period, depending on the county.
• November 1 and December 10: first installment due and delinquent.
• February 1 and April 10: second installment due and delinquent.

How to appeal a California property tax assessment

Informal review with the county assessor

Start by asking the assessor's office to explain how your value was set and giving it recent sales of similar homes. The BOE notes that this informal discussion is often a taxpayer's first step, and it costs nothing.

Filing an assessment appeal application

To appeal formally, file an Assessment Appeal Application with the clerk of the board of supervisors or the county's assessment appeals board. The regular filing period is July 2 through September 15, or through November 30 in counties where the assessor mails value notices to every secured property owner. Supplemental and escape assessments must be appealed within 60 days of the notice. The BOE posts each county's deadline.

Who must prove the value at the hearing

Usually the owner must prove the assessor's value is wrong. For an owner-occupied single-family home that is your principal residence, the burden shifts to the assessor to prove the value is correct. Ask for written findings of fact before the hearing begins if you may want to go to court later.

Common California property tax mistakes

• Budgeting with the seller's tax bill. Your bill is based on your price, not theirs.
• Forgetting the supplemental bill. It is mailed to you and not paid by your lender.
• Not filing the homeowners' exemption. It is not automatic when you buy.
• Missing a Mello-Roos tax. Check the special tax lines and the district's maximum tax before you buy.
• Appealing too late. Filing windows close September 15 or November 30, and 60 days after a supplemental notice.
• Retitling a home without checking reassessment. Transfers to children, LLCs or co-owners can trigger a new base year value; see the Prop 19 guide.

Selling? Transfer tax is a separate charge paid at closing; see California transfer tax.