California Revenue & Taxation Code
Cal. Rev. & Tax. Code § 45153
# (a)
Any person who fails to pay any fee to the state or any amount of fee required to be paid to the state, except amounts of determinations made by the board under Article 2 (commencing with Section 45201), within the time required shall pay a penalty of 10 percent of the fee or amount of the fee in addition to the fee or amount of the fee, plus interest at the modified adjusted rate per month, or fraction thereof, established pursuant to Section 6591.5, from the date on which the fee or the amount of the fee required to be paid became due and payable to the state until the date of payment.
# (b)
Any person who fails to file a return in accordance with the due date set forth in Section 45151, shall pay a penalty of 10 percent of the amount of the surcharge with respect to the period for which the return is required.
# (c)
The penalties imposed by this section shall be limited to a maximum of 10 percent of the surcharge for which the return is required for any one return.
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