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Child maintenance calculator

A weekly estimate from the Child Maintenance Service rules published for England, Scotland and Wales. It is not a CMS decision and it is not legal advice.

Check the official calculator. Use GOV.UK’s child maintenance calculator. The bands and the shared-care table are from How child maintenance is worked out and the step-by-step guide. Weekly income is the yearly figure × 7 ÷ 365. The total is rounded to the nearest penny once, at the end.

The paying parent

Three or more children use the same percentage.

Before tax. Pension contributions come off below.

Children the paying parent or their partner gets Child Benefit for. From £200 a week, that reduces the income used (11%, 14% or 16%).

Applied to each child. If the children stay a different number of nights, the CMS works that out child by child. This box uses one number for all of them.

Questions

Is this the official Child Maintenance Service calculator?

No. It applies the rates and shared-care reductions published on GOV.UK for England, Scotland and Wales, and rounds the weekly total to the nearest penny at the end. The Child Maintenance Service makes the decision. Use the official GOV.UK calculator as well.

Which income bands does it use?

Under £7 a week is the nil rate. £7 to £100 is a flat £7. £100.01 to £199.99 is the reduced rate. £200 to £800 is the basic rate (12%, 16% or 19%). £800.01 to £3,000 is the basic plus rate, with a lower percentage above £800. Income above £3,000 a week is not included.

How do overnight stays change the amount?

On a reduced, basic or basic plus rate, 52 to 103 nights reduces that child’s share by one-seventh, 104 to 155 by two-sevenths, 156 to 174 by three-sevenths, and 175 nights or more by half plus £7 a week. The weekly total cannot fall below £7. The flat rate for income of £100 or less does not change with overnight stays. If day-to-day care is equal, the CMS can decide that nothing is due for that child. This page does not make that decision.

What about Northern Ireland?

Northern Ireland has its own Child Maintenance Service. nidirect publishes the same style of rates. Use the nidirect calculator and the NI service rather than treating this page as an NI decision.

Maintenance is one number. The school run, the holiday weeks and the receipts still need a shared place.

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