Introduction to Appeals and Disputes in Child Maintenance

When parents separate, making sure children receive the financial support they need is a top priority. In the UK, the Child Maintenance Service (CMS) is the government body responsible for helping parents work out, collect, and enforce child maintenance payments. The CMS calculates how much should be paid based on each parent’s income and circumstances, and can also take action if payments are missed. If you’re new to the subject, you may want to start with an overview of child maintenance to understand the system as a whole.

Despite the CMS’s role in ensuring fair and consistent support for children, disagreements can and do arise. Many parents find themselves questioning a CMS decision – perhaps you believe the payment amount is incorrect, or you disagree with how your income or special circumstances have been assessed. Other common reasons for disputes include errors in calculating arrears, confusion about shared care arrangements, or concerns over enforcement actions.

Understanding your rights to appeal is essential. The appeals process exists to make sure decisions are fair, transparent, and based on accurate information. If you think a mistake has been made or that your situation hasn’t been properly considered, you have the right to challenge the decision. This can involve asking for a mandatory reconsideration – a review by the CMS – or, if necessary, taking your case to an independent tribunal.

Familiarising yourself with the CMS process can help you understand how decisions are made and what steps you can take if you disagree. The rules that govern child maintenance are set out in the Child Support Act 1991, which outlines the responsibilities of parents and the powers of the CMS. While the Act aimed to create a fair and effective system, it has faced criticism for issues with enforcement and communication, making it even more important for parents to know how to protect their rights.

By understanding the appeals and disputes process, you can ensure your voice is heard and that your child receives the support they deserve. If you have concerns about a CMS decision, taking timely action and seeking guidance can make a significant difference in achieving a fair outcome.

Understanding CMS Decisions and Grounds for Appeal

Understanding how the Child Maintenance Service (CMS) makes its decisions is the first step before considering an appeal. The CMS uses a set formula to work out how much child maintenance should be paid, based on factors such as the paying parent’s income, the number of children involved, and the amount of time children spend with each parent. It’s important to review how CMS calculates payments so you can identify whether there has been a genuine mistake or misunderstanding in your case.

What CMS Decisions Can Be Appealed?

Not every decision made by the CMS can be challenged, but there are several key areas where parents have the right to appeal:

  • Calculation Disputes: If you believe the CMS has incorrectly assessed your income or made an error in the calculation, you can appeal. This might include situations where the wrong income figures were used, or changes in circumstances weren’t properly taken into account.
  • Special Expenses: Sometimes, a parent may have additional costs that should be considered, such as travel expenses for seeing the child, costs related to caring for a disabled child, or repayment of debts from the relationship. These are known as special expenses, and if you think they haven’t been properly factored in, you can challenge the decision.
  • CMS Enforcement Actions: If the CMS takes enforcement action – such as deducting money directly from your wages or bank account, or taking legal steps to recover unpaid maintenance – you may be able to dispute these actions if you think they are unfair or incorrect. Learn more about CMS enforcement and what you can do if you disagree with these measures.

Understanding Special Expenses

Special expenses can have a direct impact on the amount of child maintenance you are required to pay. These expenses might include things like the cost of travelling to see your child, supporting a child with a disability, or paying off debts that were jointly incurred for the child’s benefit. If you believe you have qualifying expenses that the CMS has not considered, you can request a review. For more details on what counts as special expenses and how to claim them, see our page on special expenses.

Legal Basis for CMS Decisions

The rules and procedures the CMS follows are set out in the Child Support Act 1991. This law established the framework for how child maintenance is calculated, reviewed, and enforced in the UK. For a deeper understanding of the legal background and the challenges that have shaped the current system, you can read about the Child Support Act 1991.

Practical Advice Before Appealing

Before you begin an appeal, gather all relevant information, such as recent payslips, details of special expenses, and any letters from the CMS. Double-check the decision letter to see exactly how your maintenance was calculated and compare it with the official guidelines. If you’re unsure whether you have grounds for appeal, reviewing the CMS’s calculation methods and understanding your rights regarding special expenses and CMS enforcement can help you decide on your next steps.

Remember, challenging a CMS decision is your right if you believe an error has been made or your circumstances haven’t been properly considered. Understanding the rules and your options will give you the best chance of achieving a fair outcome.

Can I appeal if the CMS ignored my special expenses?

Steps to Appeal a CMS Decision

Steps to Appeal a CMS Decision

If you disagree with a decision made by the Child Maintenance Service (CMS), there is a clear process you can follow to challenge it. Here’s a step-by-step guide to help you understand your rights and what to expect at each stage.

1. Request a Mandatory Reconsideration

The first step in appealing a CMS decision is to ask for a mandatory reconsideration. This is a formal review where the CMS looks at your case again to check if the decision was correct. You must do this before you can take your appeal any further.

You can request a mandatory reconsideration if you believe the CMS has made a mistake, missed important information, or if your circumstances have changed since the decision was made. Common reasons include incorrect income assessments or changes in care arrangements.

2. Timeframe and How to Request a Review

You need to ask for a mandatory reconsideration within one month of the date on your CMS decision letter. If you miss this deadline, you may still be able to apply if you have a good reason, but it’s important to act quickly.

To request a review, contact the CMS directly by phone or in writing. Clearly explain why you think the decision is wrong and provide any evidence that supports your case. For a detailed overview of the CMS process, including how decisions are made and reviewed, visit our guide.

3. What Happens During the Review

After you submit your request, a different CMS officer – someone who was not involved in the original decision – will review your case. They may contact you for further information or documents.

The CMS will write to you with the outcome of the review. The possible outcomes are:

  • The original decision is changed (for example, your payment amount is adjusted).
  • The original decision is upheld (no change is made).

If you’re satisfied with the result, the process ends here. If you’re still unhappy, you can take your appeal further.

4. Escalating Your Appeal to a Tribunal

If the mandatory reconsideration does not resolve the issue, you have the right to appeal to an independent tribunal. You’ll receive a “mandatory reconsideration notice” from the CMS, which you will need to submit your appeal.

An appeal to the tribunal must usually be made within one month of the date on your mandatory reconsideration notice. The tribunal is independent of the CMS and will look at all the evidence before making a decision.

5. The Tribunal Process: What to Expect

The tribunal process is designed to be fair and impartial. You don’t need a lawyer, but you can bring someone to support you or represent you if you wish. The tribunal will review your case, listen to your side, and make a decision based on the facts and relevant law.

You will be told in advance whether your hearing will be in person, by phone, or by video. At the hearing, you’ll have the chance to explain why you think the CMS decision is wrong and present any evidence. The tribunal will then make a decision, which is legally binding.

For more detailed guidance on how to challenge a CMS decision and what to expect at the tribunal, visit Challenging what the CMS says you should get – Citizens Advice.


If you’re just starting out or need to understand the basics before appealing, see our guide on applying for child maintenance. For a full overview of each step in the CMS process, including timelines and what to expect, explore our dedicated resources. Taking action quickly and understanding your rights can help you get the best outcome for your family.

Can I appeal a CMS decision if I missed the one-month deadline?

Options After an Appeal

After your appeal to the Child Maintenance Service (CMS) has been decided, you have several options depending on the outcome and your circumstances. Understanding what happens next can help you make informed choices for your family.

If Your Appeal Is Successful

If your appeal is successful, the CMS or tribunal may change the original decision. This could mean a new calculation for child maintenance payments, a different payment schedule, or other adjustments to your case. The CMS will notify all parties of the updated decision and explain how and when the changes will take effect.

If Your Appeal Is Unsuccessful

If your appeal is not successful, the original CMS decision will stand. However, this does not necessarily mean you have no further options. In some cases, you may be able to appeal to a higher tribunal if you believe there has been a legal error. It’s important to seek advice quickly, as strict time limits usually apply for further appeals.

Changing Arrangements After an Appeal

Circumstances can change after an appeal, such as a change in income, living arrangements, or the needs of the child. If this happens, you can ask the CMS to review and vary your maintenance arrangement. To learn more about how to update your arrangement if your situation changes, see our guide on changing a maintenance arrangement.

Considering Private Child Maintenance Agreements

Some parents find that a private agreement works better after going through the formal CMS process. Private child maintenance agreements allow parents to decide between themselves how much should be paid and when. These arrangements can offer more flexibility and may help maintain a cooperative relationship. If you’re interested in exploring this alternative, visit our page on private child maintenance agreements.

Enforcement if Payments Are Missed

After an appeal, the paying parent is legally required to follow the CMS or tribunal’s decision. If payments are not made as ordered, the CMS has the power to take enforcement action to collect unpaid child maintenance. This can include deductions from wages or benefits, taking money directly from bank accounts, or even legal action in court. For more information on what the CMS can do if payments are missed, read about CMS enforcement.

Legal Framework

All child maintenance arrangements and appeals are governed by UK law. The main legislation is the Child Support Act 1991, which sets out the rules for calculating, appealing, and enforcing child maintenance. Understanding your legal rights and obligations can help you navigate the process more confidently.

If you have further questions or your circumstances change, it’s important to seek advice or revisit your arrangements to ensure they remain suitable for your family’s needs.

Can I appeal again or change payments if my situation changes?

Additional Considerations for Parents

When appealing a decision from the Child Maintenance Service (CMS), it’s important to consider how broader aspects of your family situation may influence the outcome and your ongoing obligations. Here are some key factors to keep in mind as you navigate the appeals process:

How Child Arrangements Affect Maintenance Disputes

The living arrangements for your child – such as who they live with and how often they stay with each parent – can directly impact both the calculation and responsibility for child maintenance. If there are changes to these arrangements, or if there is a dispute about where your child should live, this can lead to disagreements over maintenance payments and may form the basis for an appeal. Understanding the legal definition and implications of child arrangements can help you clarify your position and present relevant evidence during the appeals process.

Responsibilities for Adult or Disabled Children

In some cases, child maintenance obligations may extend beyond a child’s 16th birthday, particularly if your child is in approved education or training, or if they have a disability. The rules around maintenance for adult or disabled children are different from standard child maintenance, and disputes in these situations can be more complex. If your appeal relates to support for an older or disabled child, it’s important to understand your specific responsibilities and the evidence required to support your case.

Accessing Benefits and Support During Disputes

Appealing a CMS decision can be stressful, especially if it affects your financial stability. It’s vital to be aware of the benefits and support available to families with children during this time. These can include financial assistance, legal advice, and other forms of support that may help you manage while your dispute is ongoing. To explore your options, visit our overview on help if you have children, which outlines the different types of support you may be entitled to.

Housing Assistance for Parents in Disputes

Changes in child maintenance arrangements can sometimes lead to housing difficulties, especially if your household income is affected. If you are struggling to meet housing costs or need to move as a result of a maintenance dispute, it’s important to know what support is available. Our guide to housing assistance provides information on your rights and the help you can access during this challenging period.

Parental Leave and Your Rights

If you are taking time off work to care for your child – whether due to a new birth, adoption, or family changes – your income and ability to pay or receive maintenance may be affected. Understanding your entitlements to maternity, paternity and parental leave can help you plan financially and ensure you meet your legal obligations during an appeal.

Legal Framework

All decisions regarding child maintenance, including appeals and disputes, are governed by UK law. The Child Maintenance and Other Payments Act 2008 sets out the rules and processes for establishing, enforcing, and challenging maintenance arrangements. Familiarising yourself with this legislation can provide valuable context and help you understand your rights and responsibilities throughout the appeals process.

By considering these additional factors and making use of the available resources, you can better prepare for the appeals process and ensure that your family’s needs are fully addressed.


Check if Contend can help you with your issue

Solve your legal question quickly
and easily with Contend.



This material is for general information only and does not constitute
tax, legal or any other form of advice. You should not rely on any
information contained herein to make (or refrain from making) any
decisions. Always obtain independent, professional advice for your
own particular situation. Contend Inc is not regulated by the
Solicitors Regulation Authority.