California Revenue & Taxation Code
Cal. Rev. & Tax. Code § 60207
# (a)
Any person who fails to pay the amount of tax shown to be due by that person’s return on or before the last day of the month following the reporting period to which it relates, shall pay a penalty of 10 percent of the tax, together with interest on that tax at the modified adjusted rate per month, or fraction thereof, established pursuant to Section 6591.5, from the date on which the tax 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 dates set forth in Article 1 (commencing with Section 60201) shall pay a penalty of 10 percent of the amount of taxes 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 taxes for which the return is required for any one return.
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