Parents are being warned to check payments after CMS errors

Recent BBC reporting has highlighted the potentially serious consequences of errors by the Child Maintenance Service (CMS), which now handles more than 800,000 cases.

For separated parents already facing financial pressure, an incorrect calculation can mean hundreds of pounds being added to their monthly payments.

Similarly, many parents who receive a lower amount than they think is correct.

One took to parenting forum Mumsnet to say: “At the moment, the system mainly looks at PAYE income, which doesn’t always reflect someone’s actual financial situation, especially if they’re self-employed or have income from things like property (such as landlords), dividends, or company benefits, it also doesn’t take into account windfalls like inheritances.

“That can leave a lot of children missing out on support they should be receiving, as well as requiring taxpayers to pick up the slack.”

Others reported that their ex-partners were hiding income and asked for advice on how to challenge this.

Nearly £800m in child maintenance has gone unpaid since the CMS was created. It has extensive enforcement powers, but little apparent urgency about using them.

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But parents who believe their calculation is wrong can challenge the decision.

Nusrat Siddique, a solicitor at Rayden Solicitors, said: “The Child Maintenance Service calculates child maintenance in accordance with a formula and set criteria.

“Most of the time, they get it right. However, there may be instances when the CMS may have made an error or missed evidence when making their decision on a child maintenance calculation.”

She added: “If you receive a decision from the CMS which you do not agree with, you can ask them to review their decision. This process is known as seeking a mandatory reconsideration.”

How to challenge a child maintenance calculation

Parents who believe the CMS has made a mistake should first check their original decision letter.

A mandatory reconsideration normally needs to be requested within one month of the date on the decision letter. GOV.UK says parents can ask for a reconsideration if they believe an error has been made or important evidence was missed.

When making the request, parents should clearly explain why they believe the calculation is wrong and provide supporting evidence where relevant.

This could include bank statements, payslips, tax returns or medical evidence, according to the advice supplied by Rayden Solicitors.

The CMS will then review the decision and issue a mandatory reconsideration notice, explaining whether the decision has been changed and the reasons for the outcome.

What if you’ve missed the deadline?

Parents can still ask for a mandatory reconsideration after one month, but they will need to explain why the request is late.

GOV.UK gives examples including being in hospital or experiencing a bereavement.

If the parent remains unhappy after the mandatory reconsideration, they can appeal to the Social Security and Child Support Tribunal.

The appeal normally needs to be made within one month of receiving the mandatory reconsideration notice.

The tribunal is independent of government and will consider the evidence before reaching a decision.

Parents must keep paying while they challenge the decision

One important point for parents is that challenging a CMS calculation does not automatically stop the existing payment amount.

The CMS says its decision remains in place while it is being reconsidered or appealed.

Parents should therefore continue making payments according to the current calculation until the matter is resolved.

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There can also be extra costs if the CMS has to collect unpaid maintenance through its Collect & Pay service.

Parents paying using Collect & Pay have a 20% collection fee added to each amount collected.

This means parents who believe their calculation is wrong should not simply stop paying. Instead, they should follow the formal challenge process and provide evidence supporting their case.