N.J. Stat. § 17:16D-10
A premium finance company shall not charge, contract for, receive, or collect a finance charge other than as permitted by this act.
The finance charge shall be computed, using the actuarial method on the balance of the premiums due (after subtracting the down payment made by the insured in accordance with the premium finance agreement) from the effective date of the insurance coverage, for which the premiums are being advanced, to and including the date when the final installment of the premium finance agreement is payable.
Notwithstanding the provisions of R.S. 31:1-1 or any other law to the contrary, the finance charge shall be computed at a rate or rates agreed to by the premium finance company and the insured plus an additional charge of $12.00 per premium finance agreement which additional charge need not be refunded upon prepayment. However, any insured may prepay his premium finance agreement in full at any time before due date of the final installment and in such event the unearned finance charge shall be refunded.
Effective on the first day of the twelfth month following the effective date of this act, when the unpaid balance of a premium finance agreement is paid in full, or the maturity of the unpaid balance of each agreement is accelerated before the date scheduled for the payment of the final installment, the holder of the agreement shall allow a credit on account of the finance charge, calculated according to the actuarial refund method, as if all payments were made as scheduled, or if deferred, as deferred; provided, however, that if the contract is prepaid within 12 months after the first payment is due, a holder may charge a prepayment penalty of not more than (a) $20.00 on any contract up to and including $2,000.00; (b) an amount equal to 1% of the loan on any contract greater than $2,000.00 and up to and including $5,000.00; and (c) $100.00 on any contract exceeding $5,000.00.
N.J.S. § 17:16D-10