Where relevant gross weekly income exceeds £800, CMS generally applies the Basic percentage to the first £800 and a lower Basic Plus percentage to income above £800, up to £3,000. The percentages depend on the number of qualifying children. Where relevant income exceeds the £3,000 weekly ceiling, the receiving parent may be able to seek additional maintenance through the courts.
How Does Child Maintenance Work for High Earners?
Child maintenance helps meet the financial needs of eligible children after their parents separate. Under the statutory scheme, the Child Maintenance Service (CMS) generally calculates payments using the paying parent's relevant gross weekly income.
High earners do not pay a single flat percentage across their entire income. The Basic Plus calculation uses two income bands with different percentages.
The income figure can be affected by eligible pension contributions, other supported children and certain variations. The final payment may also change because of overnight shared care.
Our UK Child Maintenance Calculator homepage explains the standard calculation process. You can use the free child maintenance calculator for supported estimates.
Key distinction: The £3,000 figure is a weekly income ceiling for the ordinary CMS calculation. It is not a £3,000 maximum weekly maintenance payment.
CMS Basic Plus Rates for High Earners
The Basic Plus calculation applies when the relevant gross weekly income exceeds £800. CMS applies the ordinary Basic percentage to the first £800, then the Basic Plus percentage to income between £800 and £3,000.
| Qualifying Children | First £800 | Above £800, Up to £3,000 |
|---|---|---|
| 1 child | 12% | 9% |
| 2 children | 16% | 12% |
| 3 or more children | 19% | 15% |
What About Income Below £800?
Relevant weekly income between £200 and £800 falls within the ordinary Basic-rate band. Lower-income cases can use Reduced, Flat or Nil-rate calculations.
See our Child Maintenance Rates UK guide for all relevant income bands.
How Is Basic Plus Child Maintenance Calculated?
CMS normally uses gross annual income information obtained from HMRC, makes relevant adjustments and converts the annual income to a weekly figure.
It then applies the statutory percentages to the relevant weekly income. For an ordinary Basic Plus assessment, the calculation is split into two parts.
This formula assumes that the relevant weekly income exceeds £800. The capped amount cannot exceed £3,000 in the ordinary CMS calculation.
Example: £1,200 Weekly Income, One Child
Relevant gross weekly income: £1,200
First £800 × 12% = £96
Remaining £400 × 9% = £36
Applying 12% to all £1,200 would be incorrect for this ordinary Basic Plus example, because the second income band uses 9%.
High-Earner Child Maintenance Payment Examples
These illustrative calculations assume the stated amount is the relevant gross weekly income after applicable income adjustments. They exclude other supported children, shared care, variations and case-specific rounding.
| Weekly Income | 1 Child | 2 Children | 3+ Children |
|---|---|---|---|
| £800 | £96 | £128 | £152 |
| £1,000 | £114 | £152 | £182 |
| £1,500 | £159 | £212 | £257 |
| £2,000 | £204 | £272 | £332 |
| £2,500 | £249 | £332 | £407 |
| £3,000 | £294 | £392 | £482 |
Example: £2,000 Weekly Income for Two Children
Relevant gross weekly income: £2,000
First £800 × 16% = £128
Remaining £1,200 × 12% = £144
Example: £3,000 Weekly Income for Three Children
Relevant gross weekly income: £3,000
First £800 × 19% = £152
Remaining £2,200 × 15% = £330
These are standard combined amounts for the stated number of qualifying children. If children are in different receiving households, or have different overnight arrangements, further calculations may be necessary.
What Is the £3,000 Weekly CMS Income Ceiling?
The highest gross weekly income ordinarily taken into account by CMS is £3,000, after the relevant calculation rules have been considered.
If the paying parent's income exceeds this amount, CMS does not simply apply Basic Plus percentages to the entire excess.
What Annual Salary Equals the CMS Ceiling?
Using the CMS conversion method, £3,000 weekly is equivalent to approximately £156,429 a year. This is based on £3,000 × 365 ÷ 7.
A headline annual salary is not necessarily the same as the relevant income used by CMS. Pension adjustments or other supported children may affect the assessment.
Example: £4,000 Relevant Weekly Income
Actual relevant gross weekly income: £4,000
Ordinary CMS income ceiling: £3,000
Qualifying children: 1
£800 × 12% = £96
£2,200 × 9% = £198
The ceiling limits the gross weekly income used in the ordinary CMS calculation. Separate legal routes can potentially allow additional maintenance to be ordered by a court in qualifying circumstances.
Can a Court Order Additional Child Maintenance for High Earners?
In some high-income cases, the receiving parent may apply to the court for additional child maintenance, sometimes called a top-up order.
The Child Support Act 1991 provides the legal framework for certain additional orders where the CMS has made a maintenance calculation and relevant income exceeds the statutory ceiling.
Is Court Top-Up Maintenance Automatic?
No. A court application requires the applicable legal conditions to be met. The court considers the relevant evidence and has discretion about whether any additional amount should be ordered.
Can You Estimate a Court Top-Up by Applying 9% to Excess Income?
No. The court does not automatically extend the CMS Basic Plus percentages to earnings above the £3,000 ceiling. The amount of any additional provision depends on the law and circumstances.
England and Wales: High-income top-up applications require a distinct legal assessment. Scottish cases may involve different procedural and legal considerations. Obtain jurisdiction-specific advice for an actual case.
Do Bonuses, Overtime and Commission Affect High-Earner Maintenance?
Taxable employment earnings can include regular salary, bonuses, commission and overtime. When included in the relevant income information obtained from HMRC, these payments can affect the CMS assessment.
A large annual bonus can therefore increase relevant historic income, even if the payment was received during only one part of the tax year.
Example: £100,000 Salary Plus a £20,000 Bonus
Illustrative annual taxable earnings: £120,000
Assume no pension or other income adjustments
Weekly conversion: £120,000 × 7 ÷ 365
Relevant weekly amount: approximately £2,301.37
One-child Basic Plus calculation applies
The example is an arithmetic illustration. Actual CMS treatment depends on the relevant HMRC records, pension arrangements and current-income rules.
Explore the difference between taxable gross earnings and take-home pay in our Gross or Net Income Guide .
What About Dividends, Rental Income and Investments?
High-income parents may receive money from several sources. Not all these sources are included in the ordinary CMS income figure in the same way as salary or taxable business profits.
Additional income or assets may be considered through the CMS variation process.
| Income or Asset | General CMS Treatment |
|---|---|
| Employment earnings | Usually included in relevant taxable employment income |
| Self-employment profits | Can count as relevant taxable business income |
| Taxable occupational or personal pension income | Can form part of relevant income |
| Dividends and investment interest | May be considered through an additional-income variation |
| Rental income | May qualify for an additional-income variation |
| Certain qualifying assets | Variation rules may apply where statutory thresholds are met |
Under published GOV.UK guidance, the variation process can cover qualifying rental income and investment income over £2,500 a year, as well as certain assets worth more than £31,250.
A variation is not automatic. CMS must consider the application and evidence before changing the calculation.
GOV.UK — Additional Income and ExpensesDo Pension Contributions Reduce High-Earner Child Maintenance?
Eligible pension contributions can reduce the income used in a CMS assessment. This applies to relevant occupational and personal pension arrangements, subject to the applicable rules.
Workplace contributions may already be reflected in HMRC taxable income, while some qualifying private pension payments may need separate consideration.
Example: A Qualifying Pension Adjustment
Relevant weekly income before pension adjustment: £2,000
Eligible additional gross pension contribution: £200
Adjusted relevant weekly income: £1,800
One child: first £800 × 12% = £96
Remaining £1,000 × 9% = £90
This assumes the pension deduction is eligible and has not already been included in the starting income figure.
CMS can investigate unusually high pension contributions where a diversion-of-income variation is relevant. Do not subtract the same contribution twice.
Read Child Maintenance and Pensions for a detailed explanation.
How Do Other Children Affect Maintenance for High Earners?
CMS can adjust gross weekly income where the paying parent supports qualifying other children.
For eligible income-based cases, the standard income reductions are 11% for one other child, 14% for two and 16% for three or more.
| Other Children Supported | Income Reduction |
|---|---|
| One | 11% |
| Two | 14% |
| Three or more | 16% |
Example: £2,000 Income and One Other Child
Starting relevant gross weekly income: £2,000
11% income adjustment: £220
Adjusted weekly income: £1,780
One child receiving maintenance
£800 × 12% = £96
£980 × 9% = £88.20
This is an income adjustment, not a direct discount on the weekly maintenance amount.
See our Child Maintenance If You Have Another Child guide for eligibility and family examples.
What Happens When a High Earner's Income Changes?
High-income parents may receive fluctuating bonuses, commission or business profits. CMS ordinarily uses relevant historic annual income from HMRC, subject to its current-income and change-of-circumstances rules.
A sufficiently large difference between current income and the historic figure may qualify for a reassessment. The general current-income threshold is 25%, subject to the statutory conditions.
Can CMS Review the Case Every Year?
Yes. CMS normally performs an annual review, using updated information available through the relevant process.
Some changes may need to be reported earlier depending on the circumstances and reporting rules.
A bonus, salary reduction or new pension arrangement does not authorise a paying parent to change their maintenance payment without an appropriate CMS decision.
Free Basic Plus Child Maintenance Calculator
Enter a relevant gross weekly income and the number of qualifying children to see a simplified Basic Plus calculation. This tool is designed for illustrative high-income scenarios.
It assumes your income figure has already been adjusted where required for eligible pension contributions and other supported children. It does not determine whether an adjustment is eligible.
Calculate Your Indicative Weekly Payment
Applies the published Basic and Basic Plus percentages to relevant weekly income.
How Does This Differ from the Main Calculator?
This embedded tool specifically illustrates the two Basic Plus income bands. Our main Child Maintenance Calculator UK homepage contains the wider calculator experience for supported circumstances.
Open Main Calculator →Common Mistakes in High-Income Child Maintenance Calculations
High-income calculations can be misunderstood where parents apply a single percentage to all earnings or use income figures that have not been appropriately adjusted.
- Applying 12%, 16% or 19% to the entire income above £800.
- Applying 9%, 12% or 15% to the first £800 instead of the excess income only.
- Treating £3,000 as a maximum maintenance payment rather than an income ceiling.
- Assuming the courts automatically extend CMS percentages above £3,000.
- Ignoring taxable bonuses or commission reflected in HMRC income.
- Deducting qualifying pension contributions more than once.
- Adding investment or dividend income to salary without checking variation rules.
- Ignoring other supported children or qualifying overnight care.
- Using take-home pay instead of the relevant gross income figure.
Read our How Is Child Maintenance Calculated? guide for the full statutory calculation framework.
Official Sources on High-Income Child Maintenance
This guide concerns the statutory CMS framework for England, Scotland and Wales. Northern Ireland has a separately administered maintenance service.
The following sources explain the Basic Plus percentages, income adjustments, ceiling and variation process.
- GOV.UK — Detailed CMS Calculation Guide
- GOV.UK — How Maintenance Is Worked Out
- GOV.UK — Additional Income and Variations
- Child Support Act 1991 — Section 8
- GOV.UK — Reporting Changes
- GOV.UK — Official Maintenance Calculator
Independent Website Disclaimer: Child Maintenance Calculator UK is not affiliated with GOV.UK, DWP, HMRC or the Child Maintenance Service. Calculations are illustrative and do not replace official assessments or personalised legal advice. Court top-up questions require separate consideration.
Further details: Calculation Methodology , Editorial Policy and Disclaimer .