San Diego, California
San Diego County commercial property tax appeals
Appeals start with the San Diego County Assessor/Recorder/County Clerk and go to the San Diego County Assessment Appeals Board. Here is how commercial evidence is built, filed and heard in San Diego County.
- Assessor
- San Diego County Assessor/Recorder/County Clerk
- First-level board
- San Diego County Assessment Appeals Board
- Filing deadline
- Regular assessments: application filed with the Clerk of the Board of Supervisors between July 2 and November 30 (moved to the next business day when November 30 falls on a weekend or holiday). Supplemental and escape assessments: within 60 days of the date on the tax bill
- Commercial assessment level
- 100% of full cash value, limited to the factored base year value (Cal. Const. art. XIII A); the base tax rate is 1% of assessed value plus voter-approved debt
- Value standard
- Full cash value (Cal. Rev. & Tax. Code §110), enrolled as the lower of factored base year value and current market value (§51)
- Valuation date
- January 1 lien date for the regular roll; the date of change in ownership or completion of new construction for base year and supplemental values
- Assessment cycle
- Annual roll under Proposition 13: base year value set at purchase or new construction, factored by the inflation index (capped at 2% a year), with Proposition 8 decline-in-value reviews when market value falls below the factored base year value
- Notices mailed
- Annual assessed value information is released in July when the roll closes; supplemental and escape assessments are billed through the year after a change in ownership, new construction, or an assessor correction
How San Diego County assesses commercial property
San Diego County assesses commercial property under Proposition 13, which sets a base year value at the date of purchase or completion of new construction and allows it to rise by no more than 2% a year. Property is taxed at a 1% base rate plus voter-approved debt, so the enrolled value drives a predictable tax line until the market moves against it. When market value on the January 1 lien date falls below the factored base year value, Revenue and Taxation Code §51 requires the Assessor to enroll the lower value, which is the core of most commercial appeals in the county.
Owners have two routes. The Assessor accepts informal decline-in-value review requests in the spring, and its results are released in July. The formal route is an Assessment Appeal Application filed with the Clerk of the Board of Supervisors between July 2 and November 30, either through the Clerk's online portal or on paper. There is no filing fee. Applications are heard by three-member Assessment Appeals Board panels, and state law gives the Board two years from filing to decide.
For an evidence package, the work is an income approach under Property Tax Rule 8 supported by sales close to the lien date. Office in Downtown and Sorrento Mesa, life science in UTC, and industrial in Otay Mesa often move on different cycles, so submarket rent and cap rate evidence matters more than countywide trends.
Major commercial submarkets
- Downtown San Diego and Little Italy office
- UTC and Sorrento Mesa life science
- Carlsbad and the North County coastal corridor
- Otay Mesa and the border industrial market
- Kearny Mesa and Miramar industrial
- Mission Valley retail and hotel
Uniformity authority
Cal. Const. art. XIII, §1 (property taxed in proportion to full value) and art. XIII A, §2 (base year value and 2% inflation limit)
Appeal statute
Cal. Rev. & Tax. Code §1603 (application for reduction) and §1604 (two-year rule); Property Tax Rules 301 to 326 (Cal. Code Regs. tit. 18)
After the board
San Diego County Superior Court: after the Assessment Appeals Board decides, the owner pays the tax, files a claim for refund with the Board of Supervisors, and brings a refund action within six months of the denial of the claim (Cal. Rev. & Tax. Code §5141). The court reviews the Board's record rather than retrying value
Official forms ATALI ELECTRIC fills for San Diego County
| Form | Filed with | Purpose |
|---|---|---|
| Assessment Appeal Application (BOE-305-AH, Application for Changed Assessment) | Clerk of the Board of Supervisors, Assessment Appeals Services | Formal appeal of the regular, supplemental, escape or base year assessment. The applicant must state both the enrolled value and an opinion of value, and must indicate whether written findings of fact are requested. There is no filing fee. |
| Authorization of Agent/Designation of Attorney | Clerk of the Board of Supervisors | Required when a tax agent or attorney files or appears for the owner. Agent filings through the online portal must upload a signed authorization with the application. |
| Economic Unit Supplemental Page for Additional Parcels | Clerk of the Board of Supervisors | Adds contiguous parcels that operate as one economic unit, such as a business park or shopping center split across several APNs, to a single application. |
| Agreement to Extend Time for Assessment Appeal Hearing (2-Year Waiver) | Clerk of the Board of Supervisors | Extends the two-year period in which the Board must decide the appeal. Without a hearing or a signed waiver within two years, the applicant's opinion of value generally becomes the enrolled value under §1604(c). |
Filing system: Clerk of the Board Assessment Appeal online portal, or the paper Assessment Appeal Application filed by mail or in person at the County Administration Center
Hearings and evidence
Hearings are held before a three-member Assessment Appeals Board panel appointed by the Board of Supervisors and independent of the Assessor. The Clerk mails the hearing notice at least 45 days ahead, and parties confirm attendance no later than 21 days before the hearing. The applicant presents first, the Assessor responds, and the Board may announce its decision at the hearing or mail it later. Each party gets one postponement, requested at least 21 days before the hearing, and failure to appear can lead to denial.
- 01Exchange of information under Rev. & Tax. Code §1606 and Property Tax Rule 305.1: the initiating party submits its data with the application or at least 30 days before the hearing, and the other party responds at least 15 days before. Once an exchange occurs, evidence at hearing is generally limited to matters covered by the exchange unless the other side consents.
- 02The Assessor may request information under §441(d) before the hearing; if the owner withholds requested information and then introduces it at the hearing, the Assessor is entitled to a continuance under §441(h).
- 03Comparable sales should be close to the January 1 lien date; sales occurring more than 90 days after the lien date are not admissible (Rev. & Tax. Code §402.5).
- 04Written findings of fact must be requested on the application or before the hearing begins, and are needed if the owner may later go to Superior Court.
- 05Bring multiple sets of the evidence binder to the hearing; the Clerk recommends five copies for the panel, the Assessor and the record.
Income evidence
California's Property Tax Rule 8 governs the income approach. The Assessor values most income-producing commercial property with direct capitalization using market rent, vacancy and expenses, and the tax component is handled by loading the cap rate with the effective tax rate rather than deducting property tax as an expense. In a Proposition 8 appeal the question is whether January 1 market value is below the factored base year value, so the income evidence must show market rent and occupancy as of the lien date. Actual income is useful when it matches the market; above-market or below-market leases need to be explained, and income attributable to intangibles or business enterprise value (common in hotels and senior housing) must be removed.
Practitioner notes
- Most commercial appeals here are Proposition 8 decline-in-value appeals. A reduction lasts only for that lien date, so a building that stays below its factored base year value needs a fresh review or appeal each year.
- Base year value appeals after a purchase can be filed in the regular period for the year the value was enrolled, or within three years of enrollment if the 60-day supplemental window was missed. Allocation of a portfolio purchase price across parcels is a frequent issue.
- A reduced Proposition 8 value can be restored upward in later years, up to the factored base year value, so the 2% annual cap does not limit increases while the property recovers.
- File one application per parcel unless the Economic Unit page is used. Business parks and centers with many APNs need a consistent value conclusion across every parcel.
San Diego County appeal questions
Last verified October 2026 against the assessor, board and statute.
Is there a fee to file an assessment appeal in San Diego County?
No. The Clerk of the Board does not charge a fee to file an Assessment Appeal Application. Written findings of fact, if requested, may carry a separate charge set by the County.
How long does a commercial appeal take?
Hearings are often scheduled several months after filing, and state law gives the Assessment Appeals Board two years from the filing date to decide. If that period runs without a hearing or a signed waiver, the applicant's opinion of value generally becomes the enrolled value.
Does a Proposition 8 reduction carry forward?
Only while market value stays below the factored base year value. The Assessor reviews the value each lien date and can restore it toward the factored base year value as the market recovers, without the 2% cap applying to that restoration.
Can a consultant file for an LLC owner?
Yes. A tax agent or attorney can file and appear, but the Authorization of Agent/Designation of Attorney must be filed with the Clerk, and online agent filings must upload the signed authorization with the application.
Nearby jurisdictions
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