Supplemental or escape (out-of-period) assessment appeal: file within 60 days after mailing date on the notice of assessment (or postmark, if later)
60 days after later of the mailing date printed on the notice of assessment or its postmark, under Cal. Rev. & Tax. Code 1605(b)(1) (amended by Stats. 2001, ch. 744).
Rule text
(1) In a county other than the County of Los Angeles or a county in which the board of supervisors has adopted a resolution in accordance with subdivision (c), no later than 60 days after the date of mailing printed on the notice of assessment, or the postmark therefor, whichever is later. If the taxpayer does not receive the notice of assessment described in Section 75.31 or 534 at least 15 calendar days prior to the deadline established in the foregoing sentence, the party affected, or his or her agent, may file the application within 60 days of the date of mailing printed on the tax bill or the postmark therefor, whichever is later, along with an affidavit declaring under penalty of perjury that the notice of assessment was not timely received.
Cal. Rev. & Tax. Code 1605(b)(1) (amended by Stats. 2001, ch. 744), official source
Calculate this deadline
- Trigger (Later of the mailing date printed on the notice of assessment or its postmark): Friday, November 6, 2026.
- Exclude the trigger day and count 60 calendar days: Tuesday, January 5, 2027.
Cal. Rev. & Tax. Code 1605(b)(1) (amended by Stats. 2001, ch. 744)
(1) In a county other than the County of Los Angeles or a county in which the board of supervisors has adopted a resolution in accordance with subdivision (c), no later than 60 days after the date of mailing printed on the notice of assessment, or the postmark therefor, whichever is later. If the taxpayer does not receive the notice of assessment described in Section 75.31 or 534 at least 15 calendar days prior to the deadline established in the foregoing sentence, the party affected, or his or her agent, may file the application within 60 days of the date of mailing printed on the tax bill or the postmark therefor, whichever is later, along with an affidavit declaring under penalty of perjury that the notice of assessment was not timely received.Official source
Gov. Code 6800; Gov. Code 6707 (filings with a state agency); CCP 12, 12a, 13; agency rules 8 CCR 10600 (WCAB), 8 CCR 32130 (PERB), 22 CCR 5000 'Holiday' definition (CUIAB)
Gov. Code 6800: "The time in which any act provided by law is to be done is computed by excluding the first day, and including the last, unless the last day is a holiday, and then it is also excluded." Gov. Code 6707: "When the last day for filing any instrument or other document with a state agency falls upon a Saturday or holiday, such act may be performed upon the next business day with the same effect as if it had been performed upon the day appointed." 8 CCR 10600: "(a) The time in which any act provided by these rules is to be performed is computed by excluding the first day and including the last. (b) Unless otherwise provided by law, if the last day for exercising or performing any right or duty to act or respond falls on a weekend, or on a holiday for which the offices of the Workers' Compensation Appeals Board are closed, the act or response may be performed or exercised upon the next business day." 8 CCR 32130(a)-(b) (PERB): "(a) In computing any period of time under these regulations, except under Section 32776(c), (d), (e) and (f), the period of time begins to run the day after the act or occurrence referred to. (b) Whenever the last date to file a document falls on Saturday, Sunday, or a holiday, as defined in Government Code Sections 6700 and 6701, or PERB offices are closed, the time period for filing shall be extended to and include the next regular PERB business day. The extension of time provided herein shall be applied subsequent to the application of any other extension of time provided by these regulations or by other applicable law." CCP 12a(a): "If the last day for the performance of any act provided or required by law to be performed within a specified period of time is a holiday, then that period is hereby extended to and including the next day that is not a holiday. For purposes of this section, “holiday” means all day on Saturdays, all holidays specified in Section 135 and, to the extent provided in Section 12b, all days that by terms of Section 12b are required to be considered as holidays."Official source
- SCOPE CORRECTION: the gap listed this under Rev. & Tax. Code 1603; the supplemental/escape 60-day period is in 1605(b). Not for Los Angeles County or counties that adopted a 1605(c) resolution (assessment_appeal_supplemental_escape_60_days_tax_bill_counties). If the notice was not received at least 15 days before the deadline, 60 days from the tax bill mailing date (or postmark, if later) with an affidavit. RTC 1603(b)(4): if the county offices are closed before 5 p.m. or all day on the final date, that day is a legal holiday; a timely postmark is timely filing (RTC 166). The date shown may be earlier than the county's actual deadline. [Validation 2026-11, Q0389. Authority: Cal. Rev. & Tax. Code 1603(b)(4); Cal. Rev. & Tax. Code 166(a)]
- If the clerk's office is closed or inaccessible on the last day (weather, emergency or local closure orders), the deadline may be extended. Check local orders.
This calculator applies the cited rules to the dates you enter. It is not legal advice. Court orders, local rules, and case-specific facts can change a deadline; verify before relying on it. Rule set pending attorney review.
Worked example
Later of the mailing date printed on the notice of assessment or its postmark on Monday, March 15, 2027, personal service: due Friday, May 14, 2027.
- Trigger (Later of the mailing date printed on the notice of assessment or its postmark): Monday, March 15, 2027.
- Exclude the trigger day and count 60 calendar days: Friday, May 14, 2027.
Notes
SCOPE CORRECTION: the gap listed this under Rev. & Tax. Code 1603; the supplemental/escape 60-day period is in 1605(b). Not for Los Angeles County or counties that adopted a 1605(c) resolution (assessment_appeal_supplemental_escape_60_days_tax_bill_counties). If the notice was not received at least 15 days before the deadline, 60 days from the tax bill mailing date (or postmark, if later) with an affidavit. RTC 1603(b)(4): if the county offices are closed before 5 p.m. or all day on the final date, that day is a legal holiday; a timely postmark is timely filing (RTC 166). The date shown may be earlier than the county's actual deadline. [Validation 2026-11, Q0389. Authority: Cal. Rev. & Tax. Code 1603(b)(4); Cal. Rev. & Tax. Code 166(a)]
Related deadlines
- Property tax assessment appeal, notice of assessment not received 15 days before deadline: file within 60 days of receipt of notice (alternative 1) (60 days after)
- Property tax assessment appeal, notice not timely received: file within 60 days of mailing of the tax bill (alternative 2) (60 days after)
- Supplemental or escape assessment appeal, Los Angeles County or 1605(c) resolution counties: 60 days after mailing date on the tax bill (or postmark, if later) (60 days after)
Rules current as of 2026-10-27. Confirm against the official source and any local rule or court order before relying on a date. Rules changelog.