Child maintenance calculator: England, Wales and Scotland

Estimate weekly child maintenance with the Child Maintenance Service formula: income, number of children, other children, shared care nights and fees.

In England, Wales and Scotland, the Child Maintenance Service works out a weekly amount from the paying parent's gross income: 12%, 16% or 19% of the first £800 a week for 1, 2, or 3 or more children, then 9%, 12% or 15% up to £3,000 a week. A flat £7.00 a week applies on £100 a week or less or on certain benefits, and the amount goes down for other children the paying parent supports and for nights the children stay with them. Sources: Child Support Act 1991 Sch. 1, Child Support Maintenance Calculation Regulations 2012.

1. Before you start

Where do the parents and children live?

Result

Answer the questions above to see an estimate.

Fees

Direct Pay: no fee. Collect and Pay: 20% added for the paying parent, 4% taken off for the receiving parent (S.I. 2014/612 reg. 7).
No application fee since 26 February 2024 (S.I. 2024/87).
Announced, not yet law: the government plans to end Direct Pay and set fees at 2% for receiving parents, 2% for paying parents who pay on time and 20% for those who do not; it says legislation is expected in 2027-28 (government response, 23 June 2025). Not calculated here.

Rules used

Rule	Value	Source
Nil rate	Gross weekly income below £7.00, or a nil rate situation	Sch. 1 para. 5, reg. 45
Flat rate	£7.00 a week: income of £100 a week or less, or certain benefits	Sch. 1 para. 4, reg. 44
Reduced rate	Over £100 and under £200: £7 + T% of income above £100, T from 12.4% to 31%	reg. 43
Basic rate	12% / 16% / 19% for 1 / 2 / 3+ children, on the first £800	Sch. 1 para. 2(1)
Basic plus	9% / 12% / 15% above £800; income above £3,000 a week ignored	Sch. 1 paras. 2(2), 10(3)
Other children supported	Income reduced by 11% / 14% / 16% for 1 / 2 / 3+	Sch. 1 para. 2(3)
Shared care	52-103 nights −1/7, 104-155 −2/7, 156-174 −3/7, 175 or more −1/2 and £7 more; never below £7	Sch. 1 para. 7
Default rate (not calculated)	£39 / £51 / £64 a week when the CMS lacks information	reg. 49

Child Support Act 1991 and S.I. 2012/2677 as in force on 2026-09-27 (legislation.gov.uk). Amounts unchanged since 25 November 2013. Last verified 2026-09-27.

Not covered

Variations: special expenses (contact costs, a disabled child, debts from the relationship, boarding school, the former family home) and additional income (unearned income of £2,500 a year or more, assets over £31,250, diverted income) (regs. 63-71).
Split care, where each parent has the main care of at least one child (gov.uk).
Nights in local authority care.
The default rate used when information is missing (reg. 49).
The flat rate halved when both partners are paying parents on benefits (Sch. 1 para. 4(2), reg. 44(3)).
Cases under the older child support schemes.
The evidence of shared care the CMS accepts (court order, formal agreement or official documents).
Which income the CMS uses: the HMRC figure, or current income if it differs by 25% or more.
Northern Ireland.

Compare with the government's own child maintenance calculator and see how the Child Maintenance Service works it out.

Related: work out take-home pay with the UK salary calculator, or plan a budget with the savings calculator.

About this tool

Why use this tool

When parents separate, the Child Maintenance Service (CMS) works out how much the parent who does not have the main day-to-day care should pay, using a formula set by law. Knowing the likely amount helps you agree a private arrangement, or check a figure before you apply. This calculator applies that formula for England, Wales and Scotland, step by step, as a weekly amount.

How it works

The starting point is the paying parent's gross weekly income: taxable income after pension contributions, for the latest tax year HMRC has, divided by 365 and multiplied by 7. Below £7 a week nothing is due; up to £100 a week, or on certain benefits, a flat £7 a week is due; between £100 and £200 a reduced rate applies; from £200, the basic rate is 12%, 16% or 19% of income for 1, 2, or 3 or more children, falling to 9%, 12% or 15% on income above £800, and income above £3,000 a week is ignored (Child Support Act 1991 Sch. 1). If the paying parent or their partner gets Child Benefit for other children, income is first reduced by 11%, 14% or 16%. The amount is then split between receiving parents by number of children and reduced for shared care: one-seventh for 52 to 103 nights a year, two-sevenths from 104, three-sevenths from 156, and one-half plus £7 from 175 nights, never below £7 a week. The reduced rate percentages come from the regulations (S.I. 2012/2677, reg. 43).

Real example

A paying parent earns £31,200 a year, after pension contributions: £598.36 a week. For two children, the basic rate is 16%: £95.74 a week. If one child stays with them 60 nights a year, that child's half (£47.87) is reduced by one-seventh (£6.84), so the total is £88.90 a week, about £385.23 a month (× 52 ÷ 12). Through Collect and Pay, the paying parent would pay 20% on top and the receiving parent would get 4% less (S.I. 2014/612).

Practical tips

Equal day-to-day care means no child maintenance through the CMS: it is about who looks after the children day to day, not only nights (gov.uk). Keep evidence of shared care, such as a court order or a formal agreement. Direct Pay has no fees; there is no application fee since 26 February 2024. The government has announced it will end Direct Pay and change the fees, but this is not yet law.

Disclaimer

This is an estimate from the figures you enter, under the rules in force on 27 September 2026, for England, Wales and Scotland; it is not a decision of the Child Maintenance Service. It does not cover Northern Ireland, variations for special expenses or additional income, split care, local authority care or the default rate. Compare with the government's calculator.

Frequently asked questions

How is child maintenance worked out?⌄

The Child Maintenance Service starts from the paying parent's gross weekly income. From £200 a week, the basic rate is 12% for one child, 16% for two and 19% for three or more, falling to 9%, 12% or 15% on income above £800 a week; income above £3,000 a week is ignored. Below that there is a reduced rate (£100 to £200), a flat rate of £7 (£100 or less, or certain benefits) and a nil rate (below £7).Source: Child Support Act 1991, Sch. 1 (legislation.gov.uk)

Which income does the Child Maintenance Service use?⌄

Taxable income after pension contributions for the latest tax year HMRC has, converted to a weekly figure (÷ 365 × 7). Current income is used instead only if it differs from that figure by at least 25%. Rental income, dividends and savings interest are not included, but a variation can add them when they reach £2,500 a year.Source: Child Support Maintenance Calculation Regulations 2012, regs. 34-36 (legislation.gov.uk)

How does shared care reduce child maintenance?⌄

For each child who stays overnight with the paying parent, the amount is reduced by one-seventh for 52 to 103 nights a year, two-sevenths for 104 to 155, three-sevenths for 156 to 174, and one-half plus £7 for 175 nights or more. It cannot fall below £7 a week. If the paying parent is on the flat rate because of benefits, 52 nights or more bring it to nil.Source: Child Support Act 1991, Sch. 1 paras. 7-8 (legislation.gov.uk)

What if care is shared equally?⌄

If both parents share the day-to-day care equally, neither is treated as the paying parent and no child maintenance is due through the Child Maintenance Service. Equal nights are not enough on their own: the service looks at who provides most of the day-to-day care, such as meals, school and medical appointments.Source: Child Support Maintenance Calculation Regulations 2012, reg. 50 (legislation.gov.uk)

What do other children change?⌄

If the paying parent or their partner gets Child Benefit for other children, the paying parent's income is reduced by 11% for one, 14% for two and 16% for three or more before the basic rate is applied. Children the paying parent pays for under a court order or a private arrangement are counted in the rate, and this case keeps its share, at least £7 a week.Source: Child Support Act 1991, Sch. 1 paras. 2(3) and 5A (legislation.gov.uk)

Are there fees?⌄

Direct Pay, where the parents pay each other, has no fees. With Collect and Pay, the paying parent pays 20% on top and the receiving parent gets 4% less. There has been no application fee since 26 February 2024. The government has announced it will end Direct Pay and move to 2% fees (20% for late payers), but this needs new legislation, expected in 2027-28.Source: Child Support Fees Regulations 2014, reg. 7 (legislation.gov.uk), Government response, 23 June 2025 (gov.uk)