California Code, Revenue and Taxation Code - RTC § 2610.5

Annually, on or before November 1, the tax collector shall mail or electronically transmit a county tax bill or a copy thereof for every property on the secured roll. This requirement need not be met where no taxes are due. Failure to receive a tax bill shall not relieve the lien of taxes, nor shall it prevent the imposition of penalties imposed by this code. However, the penalty imposed for delinquent taxes as provided by any section of this code shall be canceled if the assessee or fee owner demonstrates to the tax collector that delinquency is due to the tax collector's failure to mail or electronically transmit the tax bill to the address provided on the tax roll or electronic address provided and authorized by the taxpayer to the tax collector. Penalties imposed may be canceled if the board of supervisors, upon recommendation of the tax collector, has authorized the tax collector to establish, and the tax collector has so established, specific procedures for the consideration of penalty cancellations. Those procedures may provide that penalties imposed may be canceled by resolution of the county board of supervisors upon the recommendation of the tax collector if the assessees or fee owners demonstrate to the tax collector that the delinquency is due to the county's failure to send a notice of taxes to the owner of property acquired after the lien date on the secured roll, provided payment of the amount of taxes due, minus any penalties and costs, is made no later than June 30 of the fiscal year in which the property owner is named as the assessee for taxes coming due.

With respect to a late, amended, or corrected tax bill, the penalties imposed for delinquent taxes shall be canceled if the tax amount is paid within 30 days following the date that bill is mailed or electronically transmitted.

Under no circumstance shall a taxpayer have fewer than 30 days to pay without penalty.