UK Child Maintenance Calculator


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Courts often use wrong parenting time estimates when calculating child maintenance, which could make your child maintenance either too high or too low.

Custody X Change calculates parenting time accurately, so your child maintenance will have the fairest outcome for your kids.

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Child Maintenance: How to Agree or Use the Formulas

Child maintenance (formerly child support) is the term in the U.K. that describes what one parent pays the other parent after separation to assist with the day-to-day costs of their child.

Though anyone with parental responsibility has a legal obligation to support their child financially, child maintenance is not specifically required unless one parent asks the government to calculate it.

This means that parents can reach their own agreement on child maintenance — even an agreement to have no payment at all.

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Child maintenance can become highly contentious and should be dealt with carefully. Mishandling your discussions on maintenance can damage your ability to communicate as co-parents and potentially undermine the success of any agreements you make.

Addressing this issue early on can give both parents peace of mind as you move into other aspects of the separation knowing your child is financially secure.

Paying and receiving child maintenance

Usually, the nonresident parent pays (i.e., the parent who has contact with the child but not residence).

However, parents who split time with their child equally do not typically pay or receive child maintenance. Occasionally, these parents do agree to a payment, often due to uneven incomes — but the government will not order it.

You can pay child maintenance by:

  • Giving it to the other parent in an agreed-upon form (e.g., bank transfer)
  • Direct Debit
  • Deduction from your earnings (if your employer agrees)
  • Deduction from your government benefits

The last three options incur fees.

The Child Maintenance Service (CMS) ensures payments are made correctly, though parents can opt not to involve them. To keep track of payments and child-related expenses on your own, consider a tool like the Custody X Change expense tracker.

Deciding a payment amount

Separating parents can decide a payment amount privately or through the CMS. Even if you come to an agreement yourselves, the CMS can provide useful information.

Agreeing child maintenance privately

This is encouraged by the courts in the U.K. so that families maintain autonomy over their finances. However, parents who have had abuse in their relationship should work with the CMS instead.

No law specifically states how parents who separate should arrange child maintenance. Parents are free to come to any agreement.

Whatever you agree, make sure you write it down in your parenting plan. You should include:

  • Who will pay
  • How much they will pay
  • When payments will be made
  • How payments will be made
  • When payments will end (most commonly, once the child turns 18 or finishes higher education)
  • When parents will review the arrangement
  • Repercussions for missed payments, such as late fees and penalties

You do not necessarily have to set a fixed monthly amount. You could, for example, agree that one of you will pay for certain expenses, such as educational expenses or even the home where the child lives.

If you are struggling to come to an agreement with the other parent, you may want to try mediation, which can help you sort out the sticking points. You can also use the government's formulas (detailed below) to see a recommended payment amount.

Asking the CMS to decide child maintenance

If you cannot agree on the terms of child maintenance or are separated as a result of domestic abuse, you can seek assistance from the Child Maintenance Service.

The CMS sets a legally-enforceable payment amount using the government's child maintenance formulas (outlined below). The CMS can contact both parents and HM Revenue and Customs to ascertain the paying parent's income and personal circumstances.

The entire process takes place through phone meetings and online forms. You most likely will not need to appear in person.

Before you can apply to the CMS, you must have a call with Child Maintenance Options — a free, impartial service that gives separated parents information on reaching a maintenance agreement.

UK child maintenance formulas

The CMS puts a parent into one of four categories based primarily on gross weekly income and government benefits received. The category — known as the rate — determines which formula the CMS uses to set the parent's maintenance obligation.

Gross income consists of the wages, pensions or other taxable income a parent earns. The CMS initially ignores income above £3,000 per week, savings, income from a rental property and partner's earnings. You can, however, ask the CMS to consider such factors.

A parent paying the basic or reduced rate can decrease their obligation if their residence and contact schedule gives them at least 52 overnights a year. However, their obligation cannot drop below £7 a week.

To precisely count your overnights in any month or year, use a parenting time calculator. To get an estimate of where the CMS will set your obligation, use the formulas below or the government's child maintenance calculator.

Nil rate

This means neither parent has to pay child maintenance. It applies if any of the following is true:

  • Parents spend roughly equal time with the child.
  • The parent with less time has a gross weekly income of less than £7.
  • That parent is getting a work-based training allowance as their income.
  • That parent is in prison.
  • That parent is in a care or nursing home and receiving benefits.
  • That parent is a long-term patient in hospital.

Flat rate

This means one parent pays the other £7 per week. It applies when any of the following is true for the paying parent:

  • They have a gross weekly income of less than £100.
  • They claim income support or pension credit.
  • They claim incapacity benefit, income and support allowance or invalid care allowance.
  • They claim Universal Credit with no work income.

Reduced rate

This is used when the paying parent has a gross weekly income of £100 to £200. They pay £7 per week, plus a percentage of their income over £100. The percentage depends on how many children are involved.

For example:

Susan and Jamie have one child, who lives with Susan. Jamie now lives with a new partner and her daughter.

Jamie earns £150 gross income per week and does not claim any benefits.

  1. The amount of Jamie's weekly income above £100 is £50, and he owes 14.1% of this amount.
    14.1% of £50 = £7.05
  2. He adds this total to the base of £7.
    £7.05 + £7 = £14.05
  3. He rounds to the nearest pound.

Jamie will pay Susan £14 per week for child maintenance.

Basic rate

This is used if the other three rates don't apply. It is a percentage of the paying parent's gross income.

First, the paying parent reduces their gross income for calculation purposes, depending on how many children live with them.

  • One child living with them: 11%
  • Two children living with them: 14%
  • Three or more children living with them: 16%

The parent ultimately pays a percentage of the amount left after this deduction. The percentage depends on how many children are being applied for.

For the first £800 of gross weekly income, they pay as follows:

  • One child being claimed for: 12%
  • Two children being claimed for: 16%
  • Three or more children being claimed for: 19%

If they have additional gross weekly income, they also pay a percentage — referred to as basic rate plus — on the first £2,200 remaining:

  • One child being claimed for: 9%
  • Two children being claimed for: 12%
  • Three or more children being claimed for: 15%

These two totals are then added together and rounded to the nearest pound.

For example:

Jamie and Susan have three children, who all live with Susan. Jamie lives with a new partner and her daughter.

Jamie's gross weekly income is £1,000.

  1. First, he subtracts 11% of his income because he has one child living with him.
    £1,000 - 11% = £890
  2. He owes 19% on the first £800, as there are three children being claimed for.
    19% of £800 = £152
  3. He owes 15% of the remaining £90 of his income.
    15% of £90 = £13.50
  4. He adds these amounts together.
    £152 + £13.50 = £165.50
  5. He rounds to the nearest pound.

Jamie will pay Susan £166 per week in child maintenance.

Getting an accurate calculation

Estimating your parenting time can impact your child maintenance payment by thousands of pounds a year.

As you saw above, the government's formulas allows a parent to cut their maintenance payment by more than half depending on how many nights per year they host their child.

The Custody X Change app lets you quickly calculate your exact number of overnights.

With Custody X Change, you can tweak your residence and contact schedule to see how even little changes affect your number of nights with the child. Plus, you can see how the number changes each year due to special occasion.

Whether you're paying or receiving child maintenance, make sure your parenting time calculation is exact. The number will affect you, your child and the other parent for years to come.

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