California Code, Financial Code - FIN § 18630

In the event that the insurance policy or policies which are the subject of a premium finance agreement are canceled by the insured or by the insurer, for any cause, the insured shall be entitled to receive a refund credit of the unearned finance charge.  This refund credit shall be calculated in the same manner as prescribed in Section 18629, and shall be paid to the insured within a reasonable time.