Calculate UK child maintenance using the official CMS formula with interactive shared care sliders, fee comparison, and long-term projections. Covers all 5 rate bands with step-by-step calculation breakdown.
Calculate child maintenance using the official CMS formula
Enter your information to calculate maintenance
= £577/week
Children the maintenance is being calculated for
Children the paying parent (or their partner) receives Child Benefit for
Nights per year each child stays with the paying parent
How maintenance payments are managed
Approved expenses that reduce the maintenance calculation
£46,108
11 years
£4,192
| Year | Children | Weekly | Annual | Cumulative | Notes |
|---|---|---|---|---|---|
2026 | 1 | £69.23 | £3,600 | £3,600 | |
2027 | 1 | £71.31 | £3,708 | £7,308 | |
2028 | 1 | £73.45 | £3,819 | £11,127 | |
2029 | 1 | £75.65 | £3,934 | £15,061 | |
2030 | 1 | £77.92 | £4,052 | £19,113 |
Projection assumes 3% annual inflation for maintenance amounts. Children assumed to leave at age 16. Actual amounts may differ based on CMS annual reviews.
Child maintenance is a regular financial contribution from one parent to the other towards the costs of raising their child after separation. In the UK, the Child Maintenance Service (CMS) manages approximately 790,000 active arrangements covering 1.1 million children.
There are three ways to arrange child maintenance: family-based arrangements (private agreement between parents with no fees), CMS Direct Pay (CMS calculates the amount but you pay directly, no fees), and CMS Collect & Pay (CMS handles all payments with a 20% surcharge for the paying parent and 4% deduction for the receiving parent).
The paying parent is the one who does not have the main day-to-day care of the child. This applies to biological or adoptive parents. Step-parents do not have a legal obligation to pay child maintenance.
Maintenance continues until the child turns 16, or 20 if they remain in approved full-time education (A-levels or equivalent, not university). Since April 2024, applying to the CMS is completely free.
The CMS uses a 6-step formula to determine weekly maintenance. First, the paying parent's gross weekly income is determined from HMRC data (annual income ÷ 52). Then income is reduced for any other children in the household (11% for 1, 14% for 2, 16% for 3+).
| Rate | Weekly Income | 1 Child | 2 Children | 3+ |
|---|---|---|---|---|
| Nil | Below £7 | £0 | £0 | £0 |
| Flat | £7-£100 | £7 | £7 | £7 |
| Reduced | £100-£200 | 17% | 25% | 31% |
| Basic | £200-£800 | 12% | 16% | 19% |
| Basic Plus | £800-£3,000 | 9%* | 12%* | 15%* |
* Basic Plus rate applies to income over £800/week. Income up to £800 uses the Basic rate.
After calculating the base amount, shared care reductions apply if the child stays overnight with the paying parent for 52+ nights/year. The reduction increases in bands: 1/7, 2/7, 3/7, and 1/2 (plus £7/child extra at 175+ nights).
The CMS caps income at £3,000/week (£156,000/year). For income above this, the receiving parent can apply to court for a top-up order.
All 5 rate bands accurately implemented
Per-child overnight stays with band indicators
Direct Pay vs Collect & Pay cost analysis
Compare different circumstances side by side
CMS vs Private Agreement guidance
Year-by-year until children age out
Contact costs, boarding fees, disability
Full CMS formula walkthrough
Income breakdown and shared care curves
Professional branded report download
Share calculations with QR codes
Paying vs receiving parent perspective
Other free tools to help you support your child's education
GCSE & A-Level trends, attendance statistics, and regional comparisons.
Search 20,000+ UK apprenticeships with official Government data.
Calculate UCAS tariff points from 25+ qualification types for university applications.
Calculate UK student loans, maintenance grants, and repayment projections.
Find your GCSE grade from raw marks. All exam boards, 30+ subjects, 2022-2025 data.
Calculate UK Child Benefit, HICBC charge, and pension optimization.
Check eligibility for all 10 UK education benefits across 4 nations in one place.
UK school term dates & holidays for all 4 nations. Calendar, countdown, iCal export.
Attainment 8, Progress 8, and sixth form entry checker for all UK nations.