Child Maintenance
& Overtime
How CMS Calculates Police Income Under UK Law (2026)
Snippet Definition
Does Police Overtime
Count for Child Maintenance?
Yes. In the UK, police overtime is normally included in Child Maintenance Service (CMS) calculations because it forms part of gross taxable income. Where overtime fluctuates significantly, CMS may average earnings across a tax year or reassess if income changes by 25% or more.
Section 01
The Legal Basis
Child maintenance for police officers is governed by the statutory framework of the 2012 Child Maintenance Service (CMS) scheme.
- Child Maintenance Service (CMS): The central administrative body for calculating and enforcing payments.
- Child Support Act 1991: The primary legislation underpinning the system.
- Gross Income Model: CMS now uses gross taxable income figures for its baseline.
- HMRC Data Matching: Income is automatically verified against real-time payroll data.
- Administrative Arrangements: Most police maintenance is handled via direct pay or collect-and-pay.
Authority Context
Unlike the historic 'court-ordered' maintenance models, the post-2012 CMS framework is formula-driven. For the vast majority of separating officers, the CMS takes precedence over the courts for child maintenance, provided the children reside in the UK.
What Income Counts?
| Income Type | Included? | Notes |
|---|---|---|
| Basic Pay | Yes | Core taxable salary. |
| Overtime | Yes | Recurring element of gross income. |
| London Weighting | Yes | Taxable regional allowance. |
| Regional Allowances | Yes | SSP, SEPP, and other taxable bands. |
| Mileage / Expenses | No | Non-taxable reimbursement. |
| Injury Award | Usually | Regulation B treated as income resources. |
| Pension Contributions | Reduces base | Gross income is taken post-contribution. |
Managing Overtime Fluctuations
The biggest challenge for police officers is variable overtime. A busy year with public order deployments can artificially inflate maintenance for the following 12 months.
CMS Logic
- • The 25% Rule: Income is only reassessed mid-year if it changes by 25%+.
- • Annual Review: Baseline is usually P60 data from the previous year.
- • Averaging: If you report a change, CMS may ask for 3 months of payslips.
Estimated Impact (2 Children)
£175 / week
*Assumes no shared care reduction. Overtime accounts for ~£28 of this weekly payment.
When can maintenance be Reviewed?
Change Occurs
Income rises or falls by 25% or more.
CMS Notified
Self-report via the CMS portal immediately.
HMRC Check
CMS verifies data against real-time payroll.
Revised Award
New weekly baseline is issued.
Arrears Risk: If you fail to report an income increase, the CMS can backdate the higher rate and issue an enforcement order against your police salary.
Shared Care & Shift Work
Shift patterns often make direct 50/50 care difficult to track. The CMS uses "Nights per year" as the primary metric.
| Avg Nights/Week | Reduction |
|---|---|
| Less than 1 night | No reduction |
| 1-2 nights (52-103) | -1/7th |
| 2-3 nights (104-155) | -2/7th |
| 3 nights+ (156-174) | -3/7th |
| Equal (175+ nights) | -50% & more |
Operational Complications
For officers on rotating patterns (e.g., 6-on 4-off), the total nights per year must be averaged. If your shift forces you to miss a designated night, it is generally the *actual* nights stayed that count, for which evidence (messages, diaries) may be required.
London Weighting & Allowances
Classification
Regional allowances like London Weighting (LWA), SEEP, and SSP are almost always taxable. If an item appears on your P60 as taxable gross pay, the CMS will include it in the baseline assessment.
Exemptions
Pure expense reimbursements (mileage, subsistence) are excluded as they are not taxable income. However, permanent 'flat-rate' allowances that are taxable will be counted.
Injury Awards & CMS
Under the Matrimonial Causes Act, injury awards are often treated differently as capital, but for Child Maintenance purposes, they are regular recurring income. The CMS frequently includes non-taxable Regulation B awards if they are considered general income resources.
Institutional Rule: CMS assesses the 'available' income to support the child. Recurring compensatory awards increase available income, regardless of HMRC tax status.
Public Order Spikes
The Spike
A major operation (e.g., G7, COP26) leads to a £10k income spike.
The Delay
HMRC data reflects this next year, inflating maintenance.
The Strategy
Report the income drop as soon as the operation ends to trigger reassessment.
Police Maintenance Impact Snapshot
Modelling CMS Calculations with Variable Income
Estimated CMS Target
OT Risk
Moderate exposure
Sensitivity
High volatility
Summary Basis
Based on a gross annual income of £54,000. CMS uses historical HMRC data unless a 25% change is reported.
Disclaimer: This snapshot is for illustrative purposes only. Actual CMS assessments include pension contributions, taxable benefits, and complex variation rules.
Enforcement Risks
DEO
Deduction from Earnings Order: Taken directly from police salary.
Arrears Interest
Arrears can accrue quickly during disputed overtime periods.
CMS Fees
20% fee added to all maintenance for 'Collect and Pay' users.
Civil Penalties
Fines for failing to disclose a 25% income fluctuation.
Credit Impact
Unpaid CMS triggers records on civilian credit files.
HMRC Recoup
Automated recoupment from future tax refunds.
Myth vs Reality
| Myth "Overtime doesn't count because it's not guaranteed." | Reality If it is taxable income, the CMS will include it in the calculation. |
| Myth "CMS only uses your basic salary for the baseline." | Reality It uses the 'Gross Taxable Pay' figure from HMRC. |
| Myth "A high overtime year locks in high payments forever." | Reality You can trigger a reassessment whenever income drops by 25%. |
Common FAQs
Does police overtime count for child maintenance?
Yes. In the UK, police overtime is normally included in Child Maintenance Service (CMS) calculations because it forms part of gross taxable income. Where overtime fluctuates significantly, CMS may average earnings across a tax year or reassess if income changes by 25% or more.
Is London weighting included?
Yes, London Weighting is a taxable allowance and is considered part of your gross income for CMS purposes. Almost all regular taxable allowances received by a police officer, including regional weightings and competency payments, are included in the assessment.
What if my overtime drops?
If your gross income drops by 25% or more compared to the figure the CMS is using (usually from the last tax year), you can apply for a reassessment. You will need to provide evidence, such as three months of payslips, to prove the sustained reduction in income.
Can I challenge a CMS calculation?
Yes, you can request a Mandatory Reconsideration if you believe the CMS has made an error in its calculation. If the dispute relates to what counts as income, you may need to file a 'variation' request or provide specific HMRC-verified evidence of your earnings.
Does injury award income count?
Yes, police injury awards (Regulation B) are generally treated as income for child maintenance purposes. Even though they are non-taxable under HMRC rules, the CMS regulations frequently include recurring compensatory payments as income 'available' to meet the needs of the children.
How often is maintenance reassessed?
The CMS usually performs an automated 'Annual Review' where they update your income based on the latest data from HMRC. Additionally, either parent can report a significant change in income (25% or more) at any time during the year.
What happens if I don't report income changes?
Failing to report a significant increase in income can lead to the accrual of arrears, civil penalties, and the issuance of a Deduction from Earnings Order (DEO), where maintenance is taken directly from your police salary.
Does pension income count?
Yes, if you are retired and receiving a police pension, this is taxable income and will be included in the CMS assessment. If you are still serving, your pension *contributions* usually reduce your gross income before the CMS calculation is applied.
Related Resources
This guide is a core component of the Family & Financial Law Hub. For a deep dive into pension division, see our guide on Pension Sharing Orders. You can also explore the Pay & Allowances Hub for overtime rules or use our Pension Calculator for retirement planning.
Disclaimer: This guide is provided for informational purposes only and does not constitute legal or financial advice. CMS regulations and calculations are subject to change. Always consult with a qualified professional or contact the CMS directly for an official assessment.