4.—(1) For the purposes of section 30(1) and (1A) of the 1975 Act, the employer of an earner whose employment is contracted-out by reference to a money purchase contracted-out scheme shall, subject to paragraph (2), make to the trustees of that scheme any minimum payments which fall to be made by him, other than amounts deductible by virtue of regulation 3(4) which he did not deduct, within 14 days of the end of the income tax month in which there arose the liability for Class 1 contributions in respect of the earnings to which those minimum payments relate.
(2) An employer shall for the purposes of paragraph (1) be deemed to have deducted from the last of any number of payments of emoluments which fall to be aggregated under or by virtue of paragraph 1(1) of Schedule 1 to the Social Security Act 1975(1) the amount of minimum payments deductible from those payments which he did not deduct from the earlier payments.
(3) Subject to paragraph (4), if the employer has paid to the trustees on account of minimum payments an amount which he was not liable so to pay, the amounts which he is liable so to pay subsequently, in respect of other payments of emoluments made by him during the same tax year, shall be reduced by the amount so overpaid, so however that if there was a corresponding overdeduction from any payment of emoluments to an earner the provisions of this paragraph shall apply only in so far as the employer has reimbursed the earner therefor.
(4) Paragraph (3) applies only where the overdeduction occurred by reason of an error made by the employer in good faith.