Giving every child the best start in life
A general debate on giving every child the best start in life is scheduled to take place in the House of Commons Chamber on Tuesday 15 July 2025.

This briefing sets out how the Child Maintenance Service calculates the amount of maintenance payable under the 2012 statutory scheme.
How is child maintenance calculated? (504 KB , PDF)
Child maintenance is a financial arrangement between a parent a child does not normally live with (the non-resident parent or paying parent) and the person who lives with the child and who usually provides day-to-day care for them (the person with care). If they live in Scotland, a child aged 12 to 19 and in full-time non-advanced education or training can apply for child maintenance.
It is not compulsory to have a formal child maintenance arrangement. Separated parents can arrange child maintenance themselves under a ‘family-based arrangement’. Where parents cannot agree, maintenance can be arranged through the Child Maintenance Service (under ‘a statutory arrangement’).
The information below covers how the Child Maintenance Service calculates child maintenance in Great Britain. Section 6 describes the similar, but separate, scheme in Northern Ireland.
When the Child Maintenance Service makes a maintenance calculation, there are five rates of child maintenance a paying parent may be required to pay, depending on their financial circumstances and in some cases, those of their partner.
To make a maintenance calculation, the Child Maintenance Service will look at the paying parent’s gross weekly income. It will then consider other things which may impact the amount of maintenance such as any other children they support in their household, and pension payments. It will then apply one of the five rates.
The service will take into account the number of other child maintenance arrangements the paying parent has (both statutory and family-based arrangements) and if there is any shared care of the child the arrangement is for.
This decision lasts until the date of the annual review, though parents must inform the CMS of any relevant changes. Both parents have a responsibility to report certain changes.
The Child Maintenance Service calculates maintenance based on a paying parent’s weekly gross income. Gross income is calculated before deducting income tax and national insurance, but after occupational or personal pension schemes have been deducted.
In most cases, the service will get a gross income figure from information given to HM Revenue & Customs by the paying parent, their employer, or a third party (such as their accountant). If the latest tax year is not available, the CMS uses income data from the most recent year going back to a maximum of six years.
Where the Child Maintenance Service is unable to obtain either historic or current information about the paying parent’s income, it can make a ‘best evidence assessment’ or a ‘default maintenance decision’. These can mean the paying parent may pay a higher amount (with no scope for the difference to be repaid) or pay less than they need to (meaning they may have to pay extra to make up for the amount missing).
In some cases, income that is not counted as gross income for the calculation can be included by a variation from the formula. Both the paying parent and person with care have grounds to request variations, to either reduce or increase the child maintenance due.
This may happen, for example, in cases where a paying parent has interest from savings or pays income to their partner, neither of which are automatically included in the calculation of gross income. Additionally a paying parent can ask for certain expenses to be included, such as costs (at least £10 a week) of keeping regular contact with the child that qualifies for child maintenance (such the cost of fuel or accommodation) or costs connected with supporting a child with a disability or a long-term illness.
Each year, on the anniversary of the date the paying parent was told about a child maintenance application, the Child Maintenance Service carries out an annual review. The annual review period lasts 20 days, and the decision lasts until the next annual review 12 months later, unless changes that affect payments happen before then.
How is child maintenance calculated? (504 KB , PDF)
A general debate on giving every child the best start in life is scheduled to take place in the House of Commons Chamber on Tuesday 15 July 2025.
A debate on children's health is scheduled to take place in the House of Commons Chamber on Thursday 10 July 2025. The subject for the debate was determined by the Backbench Business Committee, and the debate will be led by Dr Simon Opher MP.
An overview of funding for childcare providers in England since 2017-18.