legal aidChild Maintenance

When the parents of a child separate, both parents have a duty to financially support their child.

To help parents work out how much support should be provided a child maintenance formula has been calculated and is currently administered by the Child Maintenance Service (CMS).

The factors in deciding the level of child maintenance to be paid are first limited to the income of the non-resident parent. The gross income (before deductions) from all sources is noted and then payments of tax, national insurance and pension contributions are deducted. This net figure is then applied to a set percentage depending on the number of children the maintenance is to be paid for. This figure is then referred to as the basic rate of maintenance.

Other deductions are allowed to vary the level of child maintenance including the number of overnight stays in a week and high travel costs involved in seeing the child.

Child maintenance payments are no longer deducted from benefits such as Income Support and do not affect your entitlement to Tax Credits.

Child Maintenance arrangements - who to involve?

Parental Agreement

Parents do not have to involve the CMS if they are able to agree on the level of child maintenance to be paid. Many parents who are able to agree child maintenance between them will use the CMS formula to decide the amount to be paid.

If you are able to agree the level of child maintenance to be paid you do not need to formally involve the CMS and you do not need a Court Order.


If you are not able to reach agreement on the level of child maintenance either parent may contact the CMS whether this is just to confirm the level of maintenance to be paid or to formally deal with the collection and payment of maintenance. The initial enquiry is made by telephone or online.

The Court

The Court is only able to become involved in child maintenance decisions in limited circumstances including:-

  • where the CMS has no jurisdiction such as one parent lives abroad or is not the natural parent;
  • where the level of child maintenance is agreed and the parents also agreed to exclude the CMS;
  • where a top-up payment is sought

If a Court Order is made for child maintenance this will only exclude the CMS for an initial period of twelve months or longer if a longer period is agreed. After the date of exclusion has passed the CMS resumes jurisdiction and either parent may ask them to reassess the level of maintenance which is to be paid.

To calculate the level of child maintenance which should be paid or to check the amount you are receiving is correct please see


If you are in any doubt about whether you are the natural father of the child for whom child maintenance is being sought it is important that you tell the CMS the first time they contact you for an assessment.

If the CMS is notified immediately they will offer you a DNA test. You will need to pay for this upfront but if the test confirms you are not the father you will be reimbursed.

If you do not notify the CMS immediately about a dispute over paternity you will need to fund the DNA test yourself and independently. In those circumstances you will not be able to obtain a refund if the test shows you are not the father.

A DNA test will require the consent of the mother as to be most effective it should compare the DNA of the child with the mother and the alleged father. There are a number of DNA testing companies in the UK but it is always advisable to use a company that is recognised by the Court such as Cellmark and AlphaBiolabs.

If you have any queries about child maintenance payments or regarding paternity of your child then please contact us for further details.

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