California property tax appeal: how the assessment appeals board works

Last updated 2026-07-10

What is a California Assessment Appeals Board and who runs it?

The Assessment Appeals Board (AAB) is a quasi-judicial panel, independent from the county assessor, that settles fights between property owners and the assessor over assessed value. California Revenue and Taxation Code Section 1620 requires every county to have either a three-member Board of Equalization or a separately appointed Assessment Appeals Board. ^[1] Board members are appointed by the county Board of Supervisors. None of them work for the assessor, which matters a lot if you suspect the deck is stacked.

Big counties like Los Angeles run a standing board with full-time hearing officers. Smaller counties often have the Board of Supervisors sit as the Board of Equalization instead. The legal standard doesn't change: the assessor's value is presumed correct, and you carry the burden of proof. That sounds intimidating. It just means you show up with real evidence, not a lawyer.

The board can do exactly three things: cut your assessed value, leave it where it is, or push it higher. Increases are rare but perfectly legal, so thin evidence is a reason to stay home. The board's decision sets your assessed value for the tax year in dispute. After that, you go back to normal Proposition 13 rules, with a 2 percent annual cap on increases.

Own property in Los Angeles County? Our deeper guide to los angeles county property tax covers the county-specific filing windows and comparable-sale search tools.

What is the difference between a Prop 13 base year value and a temporary reduction?

This is the piece of California property tax almost nobody gets right. Under Proposition 13 (1978), your base year value starts at the purchase price and then climbs no more than 2 percent a year. ^[2] That base year value follows the property until it sells or gets new construction.

A second, smaller system rides on top. If the market value of your property drops below your Proposition 13 factored base year value, the assessor is supposed to reassess it at that lower market value under Revenue and Taxation Code Section 51. ^[3] This is a Proposition 8 temporary reduction, and it's the single most common reason homeowners appeal today, because the assessor doesn't always catch a value that has slipped below the cap.

Here's the catch. A Prop 8 reduction is temporary. Every January 1, the assessor rechecks the value and can raise it back toward your Prop 13 base year value if the market recovered, up to that cap but never past it. So a Prop 8 win saves you real money in a down year. It does not lock in a lower value forever the way a base year correction does.

Base year corrections are a different animal. Think your purchase price got recorded wrong, or the assessor botched the factored base year math? You can challenge that too. The window for base year corrections is generally three years from the date the assessment was first mailed, or 60 days from the assessment notice, whichever is later. ^[1]

In Santa Clara County the dynamics are similar, but the county's online portal is a lot better than most. Our santa clara property tax guide walks through their filing system.

What are the deadlines to file a California property tax appeal?

Miss the deadline and you're done for the year. California gives you two possible windows, and you need to know which one is yours.

Situation	Deadline
Assessor mailed you a notice of assessed value	60 days from the mailing date on the notice
No notice was mailed (the default for most homeowners)	July 2 through September 15 of the tax year
Change of ownership reassessment or new construction	60 days from the date of the assessment notice
Escape assessments (retroactive assessments)	60 days from the date of the escape assessment notice

The July 2 to September 15 window covers the large majority of California homeowners, because most counties don't mail individual notices unless the value moved a lot. ^[4] If September 15 lands on a weekend or holiday, the deadline rolls to the next business day.

Don't assume the 60-day clock helps you. Get a notice in April showing a big jump, and your window slams shut in June, long before September. Read your notice date. Count carefully.

Some counties run separate deadlines for supplemental assessments (triggered by a recent sale or construction). Those also carry a 60-day window from the supplemental notice mailing date.

Late filing is almost always an automatic dismissal. Boards have very little power to accept a late application. A few counties publish a narrow hardship exception, but planning around it is a mistake.

How do you file an appeal with your county Assessment Appeals Board?

It starts with one form: the Application for Changed Assessment (BOE-305-AH), published by the California State Board of Equalization. ^[5] You can pull it from the State Board of Equalization's website or grab it at your county clerk's office. Many counties use their own customized version that says the same thing.

Here's what goes on the form: your property's APN (assessor's parcel number, printed on your tax bill), the value you're appealing, the value you think is right, and the reason. Most homeowners check "Decline in Market Value" for a Prop 8 appeal or "Incorrect Base Year Value" for a Prop 13 dispute. You do not attach evidence yet. Evidence comes at the hearing.

How you file depends on the county. Los Angeles takes online filings through its Assessment Appeals Board portal. San Francisco, Sacramento, and San Diego accept mail and in-person filings. A handful of small counties still want paper only. Check your county clerk's website before you assume an online option exists.

The filing fee for a residential property is $0 in most counties. Some counties charge a modest fee for commercial parcels or for hearings above a set value, but it's nothing like the 25 to 50 percent contingency cut a property tax firm takes.

After you file, you get a case number and, eventually, a hearing date. The backlogs are real. Los Angeles County has historically taken one to three years to schedule a hearing, though the board has worked to shorten that. ^[6] While you wait, the assessor may reach out for an informal review, which can settle the case faster without a formal hearing.

Want a step-by-step filing guide with sample comparable-sale worksheets? The TaxFightBack DIY Appeal Kit walks through the BOE-305-AH and the evidence packet to have ready before your hearing.

What evidence does the Assessment Appeals Board actually accept?

The board weighs two main types of evidence: comparable sales and income or cost data. For a homeowner appealing a house, comparable sales are the standard play and the most convincing.

A comparable sale (comp) is a sale of a similar property that closed near the assessment date, which in California is January 1 of the tax year. The assessor uses a lien date of January 1, so your comps should bracket that date, ideally within three to six months on each side. ^[4] The board wants to know what your property would have sold for on that exact day.

Strong comps line up on the basics: same city or zip, square footage within 15 to 20 percent, similar age and condition, similar lot size, and a close date within six months of January 1. Three to five solid comps beats a stack of twenty. Quality wins.

Where do you find them? The county assessor's own database is public. Many counties publish sales by APN on their websites. Zillow and Redfin show recent sales but lack the detail the board likes. The best free source is your county's assessor portal. Pull sales straight from it and cite the assessor's own numbers, which the assessor's rep can't easily argue against.

Other evidence the board will take:

• A licensed appraisal (the gold standard, but it runs $400 to $800 and is usually overkill for a small residential appeal)
• Income and expense statements for rental properties
• Your own purchase price, if you bought recently in an arm's-length deal below the assessed value
• Photos showing physical defects the assessor's records miss
• Permits or assessor records proving a square footage error

What the board won't take: emotion, neighbor gossip, or the argument that taxes are just too high. It needs objective data tied to market value.

What happens at the hearing itself?

A routine residential hearing runs 15 to 30 minutes. You sit across from a hearing officer or a three-member panel. The assessor's representative goes first, because the value is presumed correct and their job is to establish that baseline. Then you present your evidence and your argument.

You don't need an attorney. Most self-represented homeowners who arrive with three to five clean comparable sales and a one-page written summary do just fine. Talk plainly, point to your exhibits by number, stay factual. "The comp at 123 Maple Street sold for $480,000 on December 15, three blocks away, same square footage" beats five minutes of complaining.

The assessor's rep will probe your comps. Expect lines like "that property is inferior in condition," "that was a distressed sale," or "the lot size is meaningfully different." Have answers ready. Show that the assessor's own comps are less similar to your home than yours are, and you win on the merits.

Some counties offer a stipulated agreement before the hearing date. The assessor's office reviews your file and proposes a reduced value as a settlement. You accept or reject it. If the offer is close to your target, take it and skip the hearing. If it's stingy, say no and go.

The board votes at the hearing or soon after. A written decision arrives by mail. If your value drops, the assessor recalculates your tax and refunds any overpayment, usually with interest at the rate set by the county.

How much can you actually save from a successful California property tax appeal?

California's base property tax rate is 1 percent of assessed value under Proposition 13, plus local voter-approved bonds and special assessments that vary by location. ^[2] In most counties the effective rate runs between 1.1 percent and 1.4 percent of assessed value once those add-ons are in.

Run the math on a real example. Your home is assessed at $700,000. Comparable sales say $600,000 is the true market value. A win knocks $100,000 off the assessed value. At a 1.2 percent effective rate, that's $1,200 a year. If the backlog means your hearing covers two tax years, you're looking at roughly $2,400 in refunds.

The California State Board of Equalization reports that Assessment Appeals Boards statewide reduce assessments in a meaningful share of the cases that reach a hearing. ^[7] There's no single clean statewide success-rate table, and I won't pretend there is. County-level data out of Los Angeles and Santa Clara consistently shows that applicants who show up with evidence win reductions more often than not.

What you save nothing on: the school bond, the fire district charge, the mosquito abatement assessment, and other special line items that appear on your bill but aren't tied to assessed value. Those are separate and can't be touched through the AAB.

One honest caveat. If your Prop 13 base year value already sits well below current market value, your appeal target is the factored base year value, not the current market. In that spot, even if prices fell, you may have no grounds for a Prop 8 reduction, because the market is still above your capped base year value. Run your own parcel's numbers before you file.

Can the board raise your assessed value if you file an appeal?

Yes. It's real and it happens. California Revenue and Taxation Code Section 1611.5 gives the board authority to raise assessed value above the assessor's original figure when the evidence supports it. ^[1] The board can set value at whatever the evidence shows is correct, even higher than the assessor's number.

In practice, boards rarely bump values on their own. The risk spikes when you appeal a property the assessor clearly undervalued, maybe from an incomplete record. Buy for $900,000 while the assessor shows $750,000, and filing an appeal is basically an invitation for the board to take a closer look.

The rule is simple: don't file unless you have solid evidence that market value is below the assessed value. If your comps say the assessed value is already fair or low, sit tight. Filing is the thing that cracks the door open to an increase.

Before you file, pull three to five recent neighborhood sales yourself. If they all point lower than your assessed value, you've got a case. If they're mixed or higher, walk away.

What if you lose, or the reduction is smaller than you wanted?

After an unfavorable decision, you have two real moves.

First, file a fresh application in the next filing window. Each year's assessment stands alone, so losing this year doesn't bar you next year. If the market keeps softening, your odds get better.

Second, seek judicial review in Superior Court under California Revenue and Taxation Code Section 5140. ^[1] This one requires paying the disputed tax first (under protest), then suing for a refund. It's expensive and slow, often years. You basically need an attorney. For most homeowners, this path only pencils out when the disputed amount is well into five figures a year.

A third route exists for cases where the board overstepped its legal authority or made an error of law: a writ of mandate in Superior Court. It's even more specialized and even more attorney-heavy.

For almost every homeowner, the practical answer is plain. Lose a small residential appeal, write down what the assessor's evidence was, build better comps, and refile next year if values stay down. The filing costs nothing. Your time is the only real investment.

Are there exemptions that can lower your bill without an appeal?

Sometimes an appeal isn't the move at all. California offers several exemptions and exclusions that shrink your taxable value with no hearing required.

The Homeowner's Exemption cuts assessed value by $7,000 for an owner-occupied primary residence. ^[8] That's about $70 to $100 a year at typical rates. Small, sure. But if you bought recently and never filed Form BOE-266, you're leaving it on the table. File once and it renews automatically. ^[10]

Proposition 19 (effective February 16, 2021) lets homeowners 55 or older, severely disabled persons, and disaster victims transfer their Prop 13 base year value to a replacement home anywhere in California. ^[9] That's a big deal if you're downsizing. The application is Form BOE-19-B, filed with the county assessor.

Parent-to-child and grandparent-to-grandchild exclusions under Proposition 19 are tighter than they were under the old Proposition 58/193 rules. Today, only a primary residence qualifies, and the transferred home's assessed value gets adjusted upward if its market value tops the transferor's taxable value by more than $1 million. ^[9] Plenty of inherited properties no longer qualify for a full exclusion. That trips up a lot of families.

Veterans' and disabled veterans' exemptions stack on top of the homeowner's exemption. The disabled veterans' exemption can exempt up to $196,262 of assessed value (2024 figure, adjusted annually) for qualifying veterans. ^[8]

None of these need an AAB hearing. You handle them straight with the assessor's office.

How does the California appeal process compare to other states?

California's process runs more formal than most, mostly because the AAB is a separate quasi-judicial body rather than a quick review by the assessor's own staff. In a lot of states, the first appeal goes right back to the assessor's office, which is an obvious conflict.

The 60-day notice window is tighter than most. Texas gives homeowners until May 15 or 30 days from the notice, whichever is later. Cook County in Illinois runs a completely different calendar, with township-specific windows. Our guide to the cook county tax assessor tax bill breaks down how Chicago-area appeals work.

Prop 13's cap means many long-term California owners sit at assessed values far below market, so appeals are less common here than in states that reassess to full market value every year. When California appeals do happen, they cluster among recently purchased homes and neighborhoods where prices dropped faster than the assessor's annual review caught.

Where California lags is the backlog. Los Angeles County has posted documented waits of two to three years for a scheduled hearing. ^[6] Most other major jurisdictions schedule within six to 18 months. The silver lining: a win covering multiple years produces a bigger refund, with interest.

Frequently asked questions

How do I find my county's Assessment Appeals Board filing deadline?

If you got an assessment notice by mail, your deadline is 60 days from the mailing date printed on it. If you got no notice, the standard window is July 2 through September 15. Confirm the exact dates with your county's Assessment Appeals Board office or clerk, since counties post this on their sites. The California State Board of Equalization also keeps a county contact directory.

Does filing an appeal stop me from paying my property tax bill?

No. You still pay on the normal due dates (November 1 and February 1 in California) while your appeal is pending. Win a reduction and the county refunds the overpaid amount with interest after the board rules. Skipping payment while you wait triggers penalties and does nothing to shield you from delinquency charges.

Can I appeal my supplemental assessment in California?

Yes. Supplemental assessments, triggered by a sale or new construction, are separately appealable within 60 days of the mailing date on the supplemental notice. The same BOE-305-AH form applies. These appeals are common when you buy a home and believe the reassessed value overshoots the actual market value at the time of purchase.

Do I need a lawyer or property tax agent to appeal in California?

No. California law flatly allows self-representation before the Assessment Appeals Board. A licensed attorney or California property tax agent (a specific license under Revenue and Taxation Code Section 1653) can represent you, but neither is required. Homeowners with three to five clean comparable sales win reductions on their own all the time.

What is the BOE-305-AH form and where do I get it?

BOE-305-AH is the Application for Changed Assessment, the form that starts a California property tax appeal. The California State Board of Equalization publishes it on its website (boe.ca.gov). Many county boards and clerks hand out their own equivalent version. Either one works. You can file without evidence attached; evidence gets presented at the hearing.

How long does a California Assessment Appeals Board hearing take?

The hearing itself usually runs 15 to 45 minutes for a standard residential case. Getting to that hearing is the slow part. Los Angeles County has posted documented backlogs of one to three years from filing to hearing date. Smaller counties often schedule within six to twelve months. Some cases settle before the hearing through an informal agreement with the assessor's office.

What is a Proposition 8 appeal and how is it different from a base year challenge?

A Proposition 8 appeal argues that current market value has fallen below your Proposition 13 factored base year value, so you should be taxed at the lower market value under Revenue and Taxation Code Section 51. A base year challenge argues the original purchase-price-based value got recorded wrong. Prop 8 reductions are temporary and rechecked each January 1. Base year corrections are permanent.

Will my taxes go back up if I win a Proposition 8 reduction?

Yes. A Prop 8 reduction isn't permanent. Every January 1 the assessor rechecks your market value and can restore it toward your Prop 13 factored base year value if the market recovered. The assessor can't push it past the base year cap. If you buy and prices rebound within a few years, expect the reduction to phase back out.

How does the California homeowner's exemption work?

The Homeowner's Exemption cuts your assessed value by $7,000 for your primary residence, saving roughly $70 to $100 a year depending on your local rate. You file Form BOE-266 once with the county assessor and it renews automatically. If you bought recently and never filed, call the assessor's office, since some counties allow retroactive claims within a limited window.

What happens if I miss the California property tax appeal deadline?

The board will almost certainly dismiss your application. California law gives the Assessment Appeals Board very little power to accept late filings, and most boards enforce the deadline hard. Your next shot is the following year's window, starting July 2. If you got a formal notice and blew past the 60-day window, you can't appeal that specific assessment.

Can a business or commercial property owner use the same appeal process?

Yes. The same BOE-305-AH form and the same AAB process apply to commercial and industrial property. Commercial cases run more complex because income-approach valuation matters alongside comparable sales. Evidence like rent rolls, vacancy rates, and cap rate data becomes central. Some commercial appeals bring in licensed appraisers. The filing deadlines match residential.

What interest rate applies to California property tax refunds after a successful appeal?

California Revenue and Taxation Code Section 5151 sets the refund interest rate at the county pool rate or 3 percent per year, whichever is lower, applied to the overpaid amount from the date of payment. In practice, rates have hovered near 2 to 3 percent depending on the county's investment pool. For large multi-year appeals with long backlogs, that interest adds up.

Sources

1. California Revenue and Taxation Code, Division 1, Part 3 (Assessment Appeals), Sections 1601-1641 and Section 5140 via California Legislative Information: Legal authority for Assessment Appeals Boards, board power to raise or lower value, judicial review process, and three-year base year correction window
2. California State Board of Equalization, Publication 29: California Property Tax, An Overview: Proposition 13 sets base year value at purchase price, limits increases to 2 percent annually, and sets the base tax rate at 1 percent of assessed value
3. California Revenue and Taxation Code Section 51 (Proposition 8 temporary reductions) via California Legislative Information: Requires the assessor to reduce assessed value to current market value when market value falls below the Prop 13 factored base year value
4. California State Board of Equalization, Assessment Appeals Manual: Standard July 2 to September 15 filing window for years where no individual notice is mailed, and January 1 lien date as the valuation date for comps
5. California State Board of Equalization, Form BOE-305-AH: Application for Changed Assessment: BOE-305-AH is the standard application form for California property tax appeals, published and maintained by the State Board of Equalization
6. Los Angeles County Assessment Appeals Board, filing and hearing information: Los Angeles County has historically taken one to three years to schedule assessment appeal hearings
7. California State Board of Equalization, Annual Report: Property Tax Assessment: Assessment Appeals Boards across California reduce assessments in a meaningful share of cases that reach a formal hearing
8. California State Board of Equalization, Homeowners and Veterans Exemptions overview: Homeowner's Exemption reduces assessed value by $7,000; disabled veterans' exemption can exempt up to $196,262 of assessed value (2024, adjusted annually)
9. California State Board of Equalization, Proposition 19 information (effective February 16, 2021): Proposition 19 allows qualifying homeowners 55 or older to transfer base year value statewide; parent-child exclusion limited to primary residence with a $1 million adjustment threshold
10. California State Board of Equalization, Form BOE-266: Claim for Homeowners Property Tax Exemption: Form BOE-266 is filed once with the county assessor to claim the $7,000 Homeowner's Exemption and renews automatically
11. Los Angeles County Office of the Assessor, Assessment Appeals filing information: Los Angeles County accepts online assessment appeal filings through the county's Assessment Appeals Board portal