California property tax appeals. Nov 30 is the line.
The regular assessment appeal period closes November 30, 2026 in Los Angeles, Orange, San Diego, Riverside, San Bernardino, Sacramento and 39 other counties. Under Proposition 13 the case is decline in value, so the owners with an appeal are mostly those who bought or built since 2019. Reserve screens every parcel against its factored base-year value and files the ones worth filing.
One state, two deadlines.
Every county opens July 2. Counties that mail notices to every owner by August 1 close September 15; everyone else closes November 30. For 2026 the Bay Area early counties are closed and the rest of the state, including every large Southern California county, is open through Monday, November 30, 2026.
November 30 counties
Applications must be received by the clerk of the Assessment Appeals Board, or postmarked, by November 30. Reserve needs your parcel list by late October to screen, collect authorizations and file.
September 15 counties
These counties mail value notices to all owners by August 1, so their regular period ended September 15. Owners here can still appeal supplemental and escape assessments within 60 days of the notice, and the next regular period opens July 2, 2027. Get the portfolio screened now so nothing is missed next cycle.
Source: California State Board of Equalization, Letter to Assessors 2026/023, 2026 assessment appeals filing periods. Confirm your parcel's county and deadline before relying on it.
How Prop 13 works when the property is commercial.
Proposition 13 covers every parcel of real property in California, commercial included. The 2020 split-roll measure (Prop 15) failed, so commercial property is still assessed on its purchase price, not its current market value.
That leaves one question that matters: is the property worth less on January 1 than the number Prop 13 has carried forward? For a property held since the 1990s, almost never. For one bought in 2019 to 2022, frequently yes, and the reduction can be large.
Set at purchase
When a property changes ownership or is newly built, the assessor enrolls a new base-year value, normally the purchase price. For entities, a change in control (more than 50% acquired by one party) triggers it; smaller interest transfers usually do not.
Up 2% a year, max
Each year the base-year value is increased by the inflation factor, capped at 2%. The result is the factored base-year value, and it is the ceiling on what you can be assessed, no matter what the market does.
Lower of the two
Proposition 8 requires the assessor to enroll the lower of factored base-year value or market value on the January 1 lien date. When market value drops below the ceiling, you are owed the lower number for that year. That is the appeal.
Illustrative. Figures depend on the parcel's base year, inflation factors applied, local tax rate area and the evidence of value on the lien date.
Decline in value, or base year.
Most California appeals are Prop 8 decline-in-value applications. Recent buyers have a second, more valuable route: challenging the base-year value itself.
One year at a time, temporary
- Test: market value on Jan 1, 2026 below factored base-year value.
- Window: the regular filing period, July 2 to Nov 30 (or Sept 15).
- Effect: reduced assessment for 2026-27. The assessor reviews annually and restores value as the market recovers, never above the factored base.
- Evidence: income and expense history, rent roll, cap-rate support, comparable sales near the lien date.
Permanent, factored forward
- Test: the enrolled base-year value exceeded the real property's market value at the change in ownership.
- Window: four years from the year the base-year value was first enrolled, so 2022 and 2023 acquisitions are still open this cycle.
- Arguments: price included furniture and equipment, business goodwill, franchise or brand value, above-market in-place leases, or was not an arm's-length market price.
- Effect: a lower base for every future year, factored up from the corrected number.
Screen by purchase date first.
Triage starts with the base-year date on the assessor's record. Anything re-based since 2019 goes to the model; anything older is usually well under market and comes off the list. Reserve then models January 1, 2026 value for each remaining parcel and flags only those that land below the factored base.
Office acquired 2018 to 2022
Peak pricing, then vacancy and cap-rate expansion. Market value on Jan 1, 2026 is often 25% to 45% below the price-based assessment in Los Angeles, Orange County and San Diego submarkets.
Retail, hotels and multifamily bought at compressed cap rates (2020 to 2022)
Where NOI did not grow into the price paid, the income approach supports a Prop 8 reduction. Hotels and restaurants often also carry a base-year argument for business and FF&E value baked into the purchase price.
New construction completed 2022 to 2025
Assessed near cost at completion. If stabilized income does not support that cost, market value is lower and the assessment should follow.
Entity-level transfers and portfolio deals
A change in control may have reset the base year without anyone treating it as a purchase. Allocation of a portfolio price across parcels is also frequently challengeable.
Franchise and net-lease restaurant real estate
Owner-occupied or fee-owned quick-service and casual-dining parcels bought or built recently. Burger King franchisees qualify for the preferred program rate on their whole portfolio, California included.
Held since before 2015
The factored base is usually far below market. No decline in value, no appeal, and no reason to pay anyone to look.
From parcel list to filed application in under three weeks.
The same process that ran the 2026 Florida season, adapted to Prop 13. You send the parcel list; we come back with the parcels worth filing, the projected reduction on each, and the authorization to sign.
Days 1 to 3: pull the record. Base-year value, change-of-ownership date, factored base-year value and current roll value for every parcel, direct from the county assessor.
Days 3 to 7: model January 1 value. The AVM values each parcel from income, comparable sales and cost evidence as of the lien date and flags parcels where market value sits below the factored base.
Days 7 to 14: authorize. One agent authorization per owner of record. Where Burger King or another franchisor holds title, we obtain the owner's signature directly, as we did in Florida.
Before Nov 30: file. Assessment Appeal Application (BOE-305-AH) with the clerk of each county's Assessment Appeals Board, opinion of value stated, decline-in-value or base-year appeal type selected. Los Angeles County tax agent registration is completed before any LA filing.
After filing: exchange and hearing. The board has two years to decide. Many applications settle with the assessor on stipulation before hearing. Refunds on a win are paid with interest, and the reduced value flows through to the next bill.
Appeals are prepared, filed and argued by Reserve Tax Group under written owner authorization, as California permits. Where a hearing calls for an appraiser or attorney, one is engaged for that parcel.
Reserve vs. the traditional model.
The traditional consulting model, one consultant reviewing properties one at a time on a 25% to 35% contingency, is a serious choice for a single trophy asset with a complex hearing. It was not built for a portfolio.
| Reserve Tax AI | Traditional consultant | |
|---|---|---|
| How parcels are screened | Every parcel in the portfolio run through the valuation model against its factored base-year value before anything is filed. Parcels with no case are told so in writing. | Manual review by a consultant, usually of the assets the client already suspects are high. Long-held parcels and small parcels are often never looked at. |
| Fee | 18% of first-year realized savings, paid once. No reduction, no fee. No retainers. | Typically 25% to 35% of savings, sometimes multi-year, sometimes with hourly or flat components for hearings and appraisals. |
| Software | Reserve Intelligence included: portfolio exposure, every appeal tracked drafted to filed to settled, documents and e-signature in one place. | Status by email and periodic spreadsheets. Portfolio dashboards, where offered, are a separate engagement. |
| Who files and argues | Reserve Tax Group, with an AVM evidence package built per parcel and appraisal or counsel engaged where a hearing needs it. | Licensed consultants and appraisers, with strong local assessor relationships. This is where the traditional model is at its best. |
| Minimum engagement | None. One parcel or one thousand. Burger King franchisees get the program rate on their whole portfolio. | Large firms concentrate on institutional portfolios; small and mid-sized owners frequently cannot get a callback in season. |
| Turnaround to a filing decision | Days. Parcel list in, flagged list and projected savings out, authorization to sign. | Weeks, driven by consultant availability during the busiest filing month of the year. |
Descriptions of the traditional consulting model reflect industry-standard contingency ranges and engagement practices and are not statements about any specific firm's terms. Compare any proposal on screening method, fee, and what is included.
Questions California owners ask.
Screen the portfolio before the window closes.
Send the parcel list or the addresses. You get the parcels worth filing and the projected reduction on each. Free, no obligation to file.
Which of my parcels are worth filing?
Tell us about the portfolio. We’ll follow up within one business day with what we need to run the screen.
- ✓Base-year value and change-of-ownership date pulled for every parcel
- ✓January 1, 2026 market value modeled against the factored base
- ✓Filed by Reserve Tax Group under your authorization before Nov 30
- ✓18% of first-year savings on wins, nothing otherwise