13.A central part of the Government’s reform of the child support system is a new way of working out child support liability. In place of the existing formula, which includes a wide range of income and expenses in the assessment, will be a simpler system of rates, based solely on:
	the non-resident parent’s* net income (taking into account a restricted range of potential income sources); and
	the number of children for whom the non-resident parent is responsible.
14.It is intended that the maintenance calculation should be based on one of three rates: a basic rate, a reduced rate or a flat rate.
	The general rule is that there should be a basic rate of liability based on a percentage of the non-resident parent's net weekly income. The percentages applied will depend on whether the non-resident parent is liable to pay maintenance for one, two or three or more children. Where the non-resident parent is also responsible for children living in his household (referred to as “relevant other children”), the basic rate is calculated by applying the percentages to the non-resident parent's net weekly income after this has been reduced to take account of the number of relevant other children.
	A reduced rate, which will be payable where the non-resident parent's net weekly income is more than £100 but less than £200.
	A flat rate, which will be payable if the non-resident parent’s net weekly income is £100 or less or he receives a prescribed benefit, pension or allowance, or he or his partner receive any prescribed benefit. It is also intended that certain categories of non-resident parent (including those with a net weekly income below £5) will have a nil rate of liability.
15.The new calculation rules allow for apportionment of the liability where there is more than one person with care*. The provisions for apportionment of liability are in Schedule 1, paragraph 6. The rates can be modified in shared care cases, that is, if the non-resident parent has any child for whom he is liable to pay child support living with him for at least one night a week. Provision for shared care is set out in Schedule 1, paragraphs 7 to 9. Maintenance liability can also be varied in exceptional cases – the provisions for varying the liability are in sections 5 to 7 of this Act.
16.Sections 4 and 7 of the 1991 Act provide that persons with care, non-resident parents and, in Scotland, qualifying children, can apply for a maintenance calculation. Section 6 of that Act (substituted by section 3) provides that parents with care who claim Income Support or income-based Jobseeker’s Allowance can be treated as having applied for a maintenance calculation. It is the duty of the Secretary of State to reach a decision on any application for which he has jurisdiction.
17.Sections 4(10) and 44 of the 1991 Act provide circumstances in which there is no jurisdiction. These provisions are amended by sections 2 and 22 of this Act.
18.Section 1 provides the basis for the maintenance calculation and the rates that will be used to determine maintenance liability.
19.Subsection (1) substitutes a new section 11 (dealing with the rules for maintenance calculations) in the 1991 Act.
Part 1: Child Support. Commentary on Sections Maintenance calculations and interim and default maintenance decisions Section 1: Maintenance calculations and terminology