California Code, Unemployment Insurance Code - UIC § 1112.5

(a) Any employer who without good cause fails to file the return and reports required by subdivision (a) of Section 1088 and subdivision (a) of Section 13021 within 60 days of the time required under subdivision (a) of Section 1110 shall pay a penalty of 15 percent of the amount of contributions and personal income tax withholding required by this report. This penalty shall be in addition to the penalties required by Sections 1112 and 1126.

(b) For purposes of subdivision (a), the amount of contributions and personal income tax required by the report of contributions shall be reduced by the amount of any contributions and personal income tax paid on or before the prescribed payment dates.

(c) The changes made to this section by the act adding this subdivision  1 shall apply on and after July 1, 2014.