What parents need to know about day-to-day care, overnight shared care, changes in living arrangements, evidence and how those arrangements can affect child maintenance.
This page explains important official guidance published by the Department for Work and Pensions on 7 August 2026.
Right First Time UK information page • Last reviewed: 25 August 2026
New Official DWP Guidance
The Department for Work and Pensions has published specific guidance explaining how a child's living arrangements affect Child Maintenance Service calculations and when parents should report changes.
The guidance identifies two separate issues that can affect child maintenance:
- Who provides most of the child's day-to-day care – this will usually determine who is treated as the receiving parent and who is treated as the paying parent.
- How many nights the child stays with each parent – this can affect how much child maintenance is payable.
What Changes Should Be Reported to CMS?
According to the official guidance, CMS should be told if a child:
- starts living with you;
- stops living with you;
- starts staying overnight with the other parent more often;
- starts staying overnight with the other parent less often;
- is now being cared for equally by both parents;
- moves into foster care;
- moves into local authority care.
Who Is the Child's Main Day-to-Day Carer?
The parent providing most of the child's day-to-day care will usually be treated as the receiving parent.
The official guidance says CMS may consider how often each parent is responsible for matters including:
Everyday Responsibilities
- Looking after the child outside school or nursery.
- Providing meals and toiletries.
- Providing school uniform.
- Providing everyday clothing.
- Arranging childcare.
- Paying for childcare.
Health, School & Activities
- Being the child's school emergency contact.
- Being the childminder's emergency contact.
- Arranging medical appointments.
- Taking the child to medical appointments.
- Arranging regular hobbies or activities.
- Taking the child to those activities.
Benefits and Financial Support
CMS may also consider who receives government financial support for the child, including:
- Child Benefit;
- Disability Living Allowance for the child;
- relevant additional Universal Credit amounts;
- other government financial support connected with the child.
Important
Receiving Child Benefit is relevant evidence, but the new guidance describes a wider examination of the child's actual day-to-day care arrangements.
What Happens if the Main Carer Changes?
CMS says a change should be reported where the existing main carer is no longer responsible for more than half of the child's day-to-day care.
This could happen because:
- the paying parent becomes the main carer;
- both parents begin sharing day-to-day care equally;
- a relative or another person becomes the main carer;
- the child enters local authority care.
Once CMS confirms that the main carer has changed, regular maintenance for that child may stop being payable to the previous main carer.
Any existing arrears do not automatically disappear simply because the child's current living arrangements have changed.
Equal Shared Care: An Important Distinction
There are two different concepts which are sometimes confused:
Equal Overnight Stays
A child may stay approximately half of the nights with each parent.
This does not automatically mean that no child maintenance is payable.
Equal Day-to-Day Care
If both parents genuinely provide equal day-to-day care and there is no main carer, the official guidance says no child maintenance needs to be paid.
The DWP guidance specifically says that having the child for the same number of nights does not automatically determine who provides most day-to-day care.
What Is Overnight Shared Care?
CMS uses the term overnight shared care when a qualifying child is looked after overnight as part of the relevant care arrangements.
If the paying parent looks after the child for at least 52 nights per year, their maintenance calculation may be reduced depending on the applicable maintenance rate.
Daytime Contact Does Not Count by Itself
Daytime contact alone cannot be used to calculate the statutory overnight shared-care reduction.
The Child Does Not Necessarily Have to Be at the Parent's Home
The August 2026 GOV.UK guidance also explains that an overnight stay may still count where the child stays somewhere else, provided that the paying parent remains responsible for the child that night and would be the person contacted in an emergency.
If somebody else is responsible for the child overnight and would deal with an emergency, the guidance says that night does not count as the paying parent's overnight shared care.
How CMS Works Out the Number of Nights
CMS looks at the child's usual arrangements over the year and converts the yearly total into an average weekly amount.
Example: Alternate Weekends
Two overnight stays every fortnight equals approximately 52 nights per year.
That is treated as an average of approximately one night per week.
Example: School Holidays
Six weeks during the summer plus two weeks over Christmas could total approximately 56 nights.
That would still fall within the one-night-per-week statutory shared-care band.
Official Shared-Care Reduction Bands
For relevant Basic, Basic Plus and Reduced Rate calculations, the number of overnight stays can reduce the maintenance amount.
| Overnight stays per year | Approximate weekly average | Shared-care reduction |
|---|---|---|
| 0–51 nights | Less than 1 night per week | No shared-care reduction |
| 52–103 nights | 1 night per week | Reduce by 1/7 |
| 104–155 nights | 2 nights per week | Reduce by 2/7 |
| 156–174 nights | 3 nights per week | Reduce by 3/7 |
| 175 nights or more | More than 3 nights per week | Reduce by one-half, followed by an additional £7 per week reduction for each relevant child in that band. |
The precise effect depends on the applicable child-maintenance rate and the circumstances of the case.
Official CMS Calculation Guidance175 Nights or More Does Not Automatically Mean £0 Maintenance
This is an important point.
Under the statutory shared-care calculation, 175 nights or more normally attracts the highest ordinary shared-care reduction: one-half plus the additional £7 reduction.
But equal or approximately equal overnight care can also cause CMS to investigate whether the identity of the main day-to-day carer has changed.
The August 2026 guidance says that where the child starts staying with the paying parent for an average of more than three nights per week, CMS will ask both parents whether the main carer has changed.
Flat Rate and Nil Rate Cases
Overnight shared care does not affect every CMS calculation in exactly the same way.
The new GOV.UK guidance explains that a paying parent may have no maintenance to pay where all of the following apply:
- the Flat Rate applies because they receive certain benefits or allowances;
- there is no additional income included in the calculation;
- the child stays with them for at least 52 nights per year.
Different rules can apply to Flat Rate cases based on low income and to Nil Rate cases.
Parents should therefore check the actual calculation rather than assuming that the overnight reduction works identically in every case.
How to Report a Change to CMS
Either parent can report a change to the child's care arrangements.
State what changed and the date on which the change actually happened.
The type of evidence CMS says it accepts depends on whether the issue is the main carer or the number of overnight stays.
Both parents may be asked for their account of what has changed.
When Should a Change Be Reported?
The official guidance says a change should be reported as soon as possible after it happens.
- You can report it on the same day it happens.
- You cannot normally report the change before it happens.
- Temporary changes should still be reported.
- Do not assume a short-term change is irrelevant.
Paying Parents Should Continue Paying
The DWP guidance says a paying parent should continue making the existing regular payments until CMS responds to the reported change.
It also states that where payments need to be updated, the update will be backdated to the date the change took place.
7-Day Evidence Upload Period
One particularly important part of the August 2026 guidance concerns supporting evidence.
After reporting a change online, the guidance says you will normally have 7 days to upload supporting evidence to your CMS account.
If you do not have online access, CMS should tell you how to provide the evidence.
Evidence CMS Says Can Show Who the Main Carer Is
The new guidance lists a much broader range of evidence for establishing day-to-day care.
Legal or Official Evidence
- Current court order.
- Guardianship order.
- Social services report.
Evidence of Responsibility
- School correspondence.
- Nursery correspondence.
- College correspondence.
- Club or activity correspondence.
- GP or medical correspondence.
- Dentist correspondence.
- Paid childcare correspondence.
Evidence of Spending on the Child
- Bank statements.
- Receipts.
- Childcare contracts.
- Contracts for activities.
- HMRC confirmation showing receipt of Child Benefit.
Important New Guidance on Evidence of Overnight Shared Care
The August 2026 guidance gives a specific list of supporting evidence CMS says it can accept when the dispute concerns the child's overnight arrangements.
CMS Says It Can Accept
- A current court order.
- A formal agreement – for example, an agreement drawn up by a solicitor.
- Another official document – for example, a report from CAFCASS or social services.
CMS Says It Cannot Accept as Supporting Evidence
- Communication only between the two parents.
- Photographs of the child.
- Social-media screenshots.
- Calendar entries.
Important: This Does Not Mean CMS Can Ignore the Whole Circumstances
The new GOV.UK guidance says that a person can still report or respond to a change even where they do not have supporting evidence.
CMS must then review the information available and make a decision.
There is also a separate statutory framework governing how shared care is determined.
This means the GOV.UK evidence guidance should be read alongside the Child Support Act 1991 and the Child Support Maintenance Calculation Regulations 2012.
CMS Says Certain Changes Will Be Checked With Both Parents
This is another particularly important part of the new official guidance.
CMS says it will contact both parents to check the information where:
- the paying parent reports that the main carer has changed;
- either parent reports a change in the number of overnight stays.
CMS says the other parent will be asked to respond with their own information about the change and any supporting evidence.
If the parents disagree, CMS says it will consider the evidence provided by both sides when making its decision.
Why This Matters
A report made by one parent about overnight shared care should not simply be confused with an agreed fact.
The guidance specifically describes a process in which the other parent is contacted where the number of overnight stays is being changed.
The GOV.UK Guidance Is Not the Whole Law
GOV.UK guidance explains how DWP says CMS will administer cases, but the underlying legal rules come from legislation.
Two particularly important provisions are Regulation 46 and Regulation 47 of the Child Support Maintenance Calculation Regulations 2012.
Regulation 46 – Determining Shared Care
Regulation 46 deals with how CMS determines the number of nights of shared care.
In determining the position, the legislation requires consideration of matters including:
- the terms of an agreement between the parents;
- a relevant court order;
- where there is no agreement or court order, whether an established pattern of shared care exists.
Regulation 47 – Assumed Shared Care
Regulation 47 provides an important rule where the parents agree in principle that care is shared but there is not enough evidence to establish the precise number of nights.
In those circumstances, CMS may make the calculation on the assumption that the paying parent has the child overnight for one night per week.
The Child Support Act 1991
Schedule 1 of the Child Support Act 1991 contains the statutory shared-care reduction structure used in maintenance calculations.
The legislation provides the familiar bands of:
- 52–103 nights – one-seventh;
- 104–155 nights – two-sevenths;
- 156–174 nights – three-sevenths;
- 175 nights or more – one-half, with the additional statutory reduction.
Keep Your Own Records
The DWP guidance specifically advises parents to keep track of changes in overnight arrangements.
Although CMS's new guidance says certain personal records such as calendar entries are not accepted as supporting evidence for a disputed overnight-care change, it is still sensible to keep your own records of:
- the actual dates the child stayed overnight;
- when an arrangement started or stopped;
- court orders and later variations;
- CAFCASS reports;
- social-services documentation;
- formal agreements;
- when you informed CMS;
- documents uploaded to CMS;
- CMS decisions and calculation notices.
Keeping an audit trail can be important if the history of the case is later disputed.
Track the Change Through Your CMS Account
The August 2026 guidance says parents can follow CMS's progress using the “Track Changes” facility within their online account.
CMS should contact the parties when a decision has been made and explain whether the maintenance payments are affected.
Until CMS actually changes the calculation, the existing maintenance arrangement remains in place.
What if You Think CMS Has Made the Wrong Decision?
A parent who believes CMS has made the wrong decision about living arrangements, shared care or the maintenance amount can normally ask CMS to reconsider the decision.
This is called a Mandatory Reconsideration.
Updated information or new supporting evidence can be particularly important where CMS has made its decision using incomplete or incorrect information.
Mandatory Reconsideration CMS Complaints & AppealsIf You Challenge a Shared-Care Decision
Consider identifying precisely what part of the decision you say is wrong rather than simply stating that you disagree.
State the exact date on which you say the care arrangement changed.
Explain the normal weekly, fortnightly or annual arrangement.
Refer to any court order, formal agreement, CAFCASS documentation or other relevant official evidence.
Where relevant, refer to Regulation 46, Regulation 47 and Schedule 1 of the Child Support Act 1991.
Ask what number of nights it has accepted, what period it used and what evidence it relied upon.
Check the decision notice carefully because it should tell you how and when to challenge the decision.
Useful Questions to Ask CMS
If there is a disagreement about shared care or living arrangements, these are useful questions to put to CMS in writing:
- What exact number of overnight stays has CMS recorded?
- What 12-month period, or alternative period, has CMS used?
- What date has CMS treated as the effective date of the change?
- What evidence did CMS rely upon?
- Was information obtained from both parents?
- If the parents disagreed, how did CMS resolve the conflicting information?
- Did CMS consider the terms of any relevant court order or agreement?
- Did CMS consider an established pattern of shared care?
- Was Regulation 47 considered if shared care was agreed in principle but the precise number of nights was disputed?
- If care is approximately equal, what evidence did CMS consider when deciding who provides the greater amount of day-to-day care?
The Key Safeguard
A parent's statement that living arrangements have changed is important information, but it is not automatically the same thing as an agreed or proven fact.
The new DWP guidance expressly describes a process for disputed overnight arrangements in which CMS contacts both parents and considers the evidence supplied.
At the same time, the legislation contains its own rules governing agreements, court orders, established patterns of shared care and the statutory assumption that may be used in some cases.
Parents should therefore check not only the final amount of the calculation but also how CMS reached the underlying factual decision about the child's care.
Official Sources
The information on this page is based on official UK Government and legislation sources.
https://www.gov.uk/guidance/telling-the-child-maintenance-service-about-living-arrangements
This page provides general public information about the Child Maintenance Service and explains published government guidance and legislation. It is not legal advice and does not determine the outcome of an individual CMS case.
Child maintenance decisions depend on the individual circumstances, evidence, applicable legislation and the effective date of the relevant decision.
Where a CMS decision is disputed, check the decision notice and the current GOV.UK guidance before taking action.