Subject to paragraph (2) and regulations 4 and 5, interest shall be payable with respect to any amount of child support maintenance due in accordance with a maintenance assessment and not paid by the date specified by the Secretary of State in accordance with regulations made under section 29 of the Act (the “due date”), and shall be payable in respect of the period commencing on that day and terminating on the date that amount is paid.

Subject to paragraph (3), interest with respect to arrears shall only be payable if the Secretary of State has served an arrears notice in relation to those arrears, and shall not be payable in respect of any period terminating on a date earlier than 14 days prior to the date the arrears notice is served on the absent parent.

Where the Secretary of State has served an arrears notice, the provisions of paragraph (2) shall not apply in relation to further arrears unless the conditions mentioned in regulation 2(4) are satisfied.

Subject to paragraph (6), where, following a review under section 18 or 19 of the Act or an appeal under section 20 of the Act, a fresh maintenance assessment is made with retrospective effect, interest in respect of the relevant retrospective period shall be payable with respect to the arrears calculated by reference to that fresh assessment.

The provisions of paragraph (4) shall apply to a fresh assessment following a review under section 18 or 19 of the Act or an appeal under section 20 of the Act prior to any adjustment of that assessment under the provisions of regulation 10.

For the purposes of paragraph (4), where the review under section 18 or 19 of the Act or an appeal under section 20 of the Act results in an increased assessment, and arrears in relation to that assessment arise, no interest shall be payable with respect to the arrears relating to the additional maintenance payable under that assessment in respect of any period prior to the date the absent parent is notified of the increased assessment.