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R&T Code §2512 A mailed tax payment is considered timely when it is postmarked on or prior to the delinquency date by the United States Postal Service (foreign postmarks and private metered postage are not acceptable).
R&T Code §2610.5 Failure to receive annual tax bill is never grounds to cancel a tax penalty.
R&T Code §4911.1(a) If the taxpayer can demonstrate that the current taxes were paid on a wrong parcel by mistake; Tax Collector shall cancel the credit on the unintended property and transfer the payment to the property intended; provided the payment was received on time for the correct amount of the tax due and before the property has transferred ownership, and before two years have elapsed since the date of payment.
R&T Code §4920-4925 A penalty may be canceled if the taxpayer can demonstrate that prior year taxes were paid on a wrong parcel by mistake and the payment was received on time for the correct amount of the tax due.
R&T Code §4985 A penalty may be canceled upon showing proof that the payment was not made timely, or made in the proper amount, because of information expressly given to the taxpayer in writing by the County.
R&T Code §4985.2 A penalty may be canceled if the failure to pay on time is shown to be for reasons outside taxpayer's control, provided the taxpayer is not negligent. Failure of the post office to postmark mail timely does not constitute grounds for penalty cancellation under this section.
R&T Code §4986 A penalty may be canceled to correct a specified error on the part of the County.