17 Calculation and making of deduction or repayment where tax deduction card held.

(1) On any payment of emoluments to or on behalf of an employee in respect of whom the employer holds a tax deduction card, the employer, except where these Regulations otherwise provide, shall ascertain—

(a) firstly, the cumulative emoluments of that employee at the date of the payment,

(b) secondly, by reference to the cumulative standard rate cut-off point specified on the tax deduction card corresponding to the date of payment, the cumulative gross tax in respect of the cumulative emoluments, and

(c) finally, by reference to the cumulative tax credits specified on the tax deduction card corresponding to the date of payment, the cumulative tax in respect of the cumulative emoluments.

(2) If the cumulative tax ascertained in accordance with paragraph (1) of this Regulation, exceeds the cumulative tax corresponding to the employee's cumulative emoluments at the date of the last preceding payment of emoluments (hereafter in this Regulation referred to as the “previous cumulative tax”), the employer shall deduct the excess from the emoluments on making the payment in question.

(3) If the cumulative tax as so ascertained is less than the previous cumulative tax, the employer shall repay the difference to the employee on making the payment in question.

(4) If the cumulative tax is equal to the previous cumulative tax, no tax shall be either deducted or repaid when the payment in question is made.

(5) Where the payment in question is the first payment in the year, paragraphs (2), (3) and (4) of this Regulation shall not apply, but the employer shall deduct the cumulative tax as ascertained in accordance with paragraph (1) of this Regulation from the emoluments on making the payment in question.

(6) The employer shall record, either on the tax deduction card or in such other form as may be authorised by the Revenue Commissioners, the following particulars regarding every payment of emoluments which the employer makes to or on behalf of the employee, namely -

(a) the date of the payment;

(b) the gross amount of the emoluments;

(c) in relation to the date of payment—

(i) the cumulative emoluments;

(ii) the cumulative tax due at the standard rate of tax;

(iii) the cumulative tax due at the higher rate of tax; and

(iv) the cumulative gross tax;

(d) the corresponding cumulative tax; and

(e) the amount of tax, if any, deducted or repaid on making the payment.