My ex has moved in with a new partner and children. Do I now get less child maintenance?

Many separated couples choose to come to an agreement about maintenance for their children using the Child Maintenance Service (CMS) calculator to form the basis of their payment arrangement. Several factors are used to reach a figure, such as the paying parent’s gross earnings and the amount of overnight care. But what if your ex has moved in with their new partner, who has children? Will the child maintenance they pay be reduced? Read on to find out.

If you have concerns about your money or children and you feel you need legal advice, contact specialist family solicitor Mark Heptinstall of Slater Heelis Solicitors. He is recognised as a ‘Leading Individual’ in The Legal 500 and ranked in Chambers UK, and is described as having “the amazing ability to bring calm into troubled waters”.

Can my ex change the amount of child maintenance they pay?

If you have an agreement with your ex outside of the CMS, you should first talk to them about any changes that could be in the pipeline, and if an agreement can’t be reached, then an application may be made to the CMS. But fundamentally, without the CMS being involved, your ex can simply alter the amount they pay. This may mean that you have to apply to the CMS to get the matter resolved.

For those cases already determined by the CMS, then if there is a substantial change in your’ ex’s income or circumstances, then they may be able to ask it to adjust or vary the level of child maintenance payments. Living with their new partner’s children may well come into this category.

Child maintenance arranged via the CMS is considered to be a priority payment which must be kept up to date ahead of any unsecured debts or credit cards. Just stopping payments can lead to serious consequences, such as court action or an attachment of earnings that take payments directly from wages or benefits. So the importance of informing the CMS in the prescribed way if there is a change in circumstances for either party cannot be understated.

Is child maintenance reduced if my ex’s partner’s children lives with them?

The paying parent’s gross income is reduced by a certain percentage depending on how many children live with them. This includes children of their new partner. If one child is living with the paying parent, their gross income is reduced by 11%, for two children the reduction is 14%, and for three children or more it is 16%. After these deductions are made, child maintenance is calculated as a percentage of the remaining amount. If your child stays with the paying parent overnight, then this may reduce the amount of child maintenance payable even further.

It is important to note, that a child is considered to be anyone under the age of 16 or someone between 16 and 20 who is not, nor has ever been, married or in a civil partnership and is in full-time non-advanced education.


What happens if my ex just stops paying child maintenance?

Here is a list of some of the things that can happen to your ex if they just stop paying. They could:

  • Be taken to court and fined or, in severe cases, sent to prison
  • Have their passport confiscated if more than £1,000 is owed in unpaid maintenance
  • Have their bank account frozen or have an attachment of earnings enforced that takes payments directly out of their salary before it is paid
  • Have a charging order registered against their property, which means that your ex’s assets can be used to cover any unpaid child maintenance
  • The CMS could take deductions from their tax credits or benefits
  • If they are self-employed, the CMS can enter into a direct recovery of debts arrangement whereby the CMS collects payments directly from their bank account
  • If a CMS debt exceeds £2,000, they may be refused a visa (if applying for one)
  • Avoiding child maintenance payments can cause their credit rating to suffer as the CMS keeps records of all unpaid child maintenance debts
  • Any unpaid child maintenance debts will remain on their credit file for 6 to 7 years.

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