Guide to the Child Support Agency

This guide is currently being updated – 13 February 2011
Updated 13 March 2007
Added: 28 January 2005February 2011.
This guide is now well out of date and we are hoping to get it updated asap.
Meanwhile, you will find more useful the guide which the CMEC (Child Maintenance and Enforcement Commission) have prepared specifically for MPs and their staff. 

‘An introduction to the child maintenance system’. It is here (PDF 349KB).


  • Introduction
  • Choices available to parents
  • Child Maintenance Options – a new information and support service
  • Child Support Agency
  • Enforcement: what happens when a non-resident parent doesn’t pay?
  • Child maintenance and benefit claims
  • The future child maintenance statutory scheme
  • Frequently asked questions
  • Leaflets available for your constituents


This guide to understanding how the CSA works has been compiled, with advice from those who work within the Agency, to help you deal with casework as efficiently and effectively as possible.  If you have any helpful hints you would like to add please let us know, using the Feedback Form.

We are unable to answer detailed questions about the working of the CSA.  If you work for an MP and need specific advice about casework you are handling, use our List of MP’s Hotlines to contact the office covering your area.

Index (click on the section you want):

  1. Jargon
  2. What to expect
  3. Background to the CSA system
  4. Old rules
  5. New rules
  6. Stages of the process
  7. Your role
  8. Useful websites


The Child Support Agency interprets and enforces laws laid down by parliament. The original aim of the Agency, often quoted by the management, was to eradicate child poverty in the UK.

1.  Jargon

Parent With Care (PWC).  A PWC has a child living with him or her for at least half the time.  If care is shared equally between two parents, the parent receiving child benefit is the PWC and can claim child support from the other parent.

Non Resident Parent (NRP), formerly known as the ‘absent’ parent. Normally an NRP will be the parent who does not have the QC (see qualifying child) staying overnight in their home. It is possible, however, for an NRP to have overnight care of a QC for an average of up to 3 1/2 days a week and still be an NRP.

Person(s) with care (PeWC) is/are any person or people (often grandparents), not the parent of a child, who is (are) primarily responsible for the care of that child.  They can claim child support from both or either parent.

Qualifying child/ren (QC) is/are the child/ren, which the PWC includes in his/her claim against the NRP, where paternity is confirmed.

New rules (legislation) cover cases instigated, or having certain changes, after 3rd March 2003 .

Old rules (legislation) cover cases running before 3rd March 2003 unless “pulled” into the new system by specific changes.

The Effective date is the date from which a NRP is due to pay maintenance, regardless of when he/she actually starts.

Arrears are the amount of payment due from the effective date to the start of payments through the CSA.  Can be reduced by voluntary payments made to the PWC during this period.  Arrears can also build up through non-payment, e.g. if the NRP suddenly decides to stop paying maintenance.

Shared care only exists when a child stays overnight with the NRP on a regular basis.  Under old rules it must be the equivalent of 2 nights a week, under new rules 1 night a week.

Maintenance Enquiry Form (MEF) – the initial form sent to an NRP when a new child support case is opened.

Protected income is the proportion of an NRP’s income, which must be left for him/her to live on.

Interim Maintenance Assessment (IMA) (used for cases under the old rules) is put in place when the NRP has not provided sufficient information for a Maintenance Calculation to be made.

Default Maintenance Decision (DMD) (used for cases under the new rules) – see Interim Maintenance Assessment.

Formal Maintenance Assessment (FMA) this is the completed maintenance assessment when all the required information has been provided.

2.  What to expect  

Many cases run smoothly under the CSA and many children and their carers are receiving money they would otherwise have had to do without.  Unfortunately the people you will be dealing with are those who are not happy about the system.

The main complaints from PWCs are the length of time taken to process their cases, or that they feel the NRPs are not paying enough.

The main complaints from NRPs will be that they think they are paying too much or that they don’t think they should be paying at all.

3.  Background to the CSA system

Child Support cases can be covered by one of two schemes – old rules and new rules.

The CSA also uses two computer systems.  The original CSCS system and the new CS2 system, introduced at the same time as the new rules regulations.

The original plan was to bulk migrate all cases from CSCS to CS2 by mid 2003, but so far system problems have prevented this.

4.  Old rules  

Cases received and actioned before 2nd March 2003 are often old rules.  There are however various ways an old rules case can be changed to new rules.

Example 1: If a fresh claim is made against an NRP under new rules any existing old rules case, where he/she is NRP, will be changed to new rules.

Example 2: A private (i.e. non- benefit) PWC can chose to close an old rules case and re-open under new rules after 13 weeks. If a fresh claim is made within 13 weeks it is still assessed under old rules.  Arrears from his/her old rules case can still be collected.

Under old rules the effective date was set when a MEF was deemed to have been received by an NRP.

Old rules cases may still be managed by the old CSCS computer system.  Some have migrated to the new computer system.

Old rules cases were much more complicated taking into account many pieces of information including

  • The NRP’s housing costs.
  • The PWC’s income.
  • The NRP partner’s income.

If a case migrates directly to new rules without being closed for at least 13 weeks, the maintenance payment will be “phased” down or up to the new payment over a maximum of 6 years.

It is important when contacting the CSA that you know whether a case is running under old rules or new rules.

Interim Maintenance Assessment (IMA)  

There are four categories of IMA:

Category AA category A IMA will be appropriate when the NRP fails to provide the information required to calculate an MA. This is usually when the NRP has not returned the MEF or other information requested.Category BThe NRP fails to provide information about a partner’s income  or A PWC fails to supply information about her partner’s income if there is a natural child of their relationship.Category CThe NRP is self-employed and cooperating but cannot produce evidence to confirm their business income immediately.Category  DThe NRP is not cooperating in providing the necessary evidence and verification to make a formal maintenance assessment, a Cat A IMA is in force and information has been received to indicate that the NRP is a high earner than at the time the Cat A IMA was imposed and /or there is a belief that the NRP accepted the Cat A IMA, knowing or expecting that the formal maintenance assessment would be at a higher rate because of earnings.

5.  New Rules  

Any claim received after 3rd March 2003 is a new rules case. Even if a case was received before this date if a NRP did not receive a Maintenance Enquiry Form (MEF) before 1st March 2003 it is still new rules.

Under new rules an effective date is set by first contact with a NRP.  This can be by a telephone call or the date of issue of a MEF.

New rules cases are normally actioned on the new child support 2 (CS2), computer system. Some cases cannot be handled by the new computer system and will become clerical.

New rules simplify the CSA process by considering mainly only 4 pieces of information:

  1. How much is an NRP earning?
  2. Has he/she any children in his/her household?
  3. How many QC does he/she have to pay for?
  4. Does he/she have shared care of any of the children?

The maximum maintenance calculated can be is 30% of a NRP’s net income.  When arrears are deducted the protected income is 60% of his/her net income.

Default Maintenance Decisions

In new rules Interim Maintenance Assessments have been replaced with Default Maintenance Decisions (DMD).  If the NRP has not provided sufficient information for a Maintenance Calculation to be made, a Default Maintenance Decision can be calculated. The NRP will be liable for the Default rate based on the number of more qualifying children:

  • £30 where there is one more qualifying children
  • £40 where there are two more qualifying children
  • £50 where there are three or more qualifying children

6.  Stages of the process

6.1  Maintenance Calculation (MC)

MC staff have the responsibility of gathering all required information and using it to calculate how much a NRP should be paying each week. They also recalculate where there is a change of circumstances.

Most problems occur when a NRP is non-compliant.

Under old rules there were many ways a NRP could delay a case and there are plenty of web sites specialising in telling NRPs how to avoid contributing to the upkeep of their children.

The new rules system is much simpler, but there are still ways to get round the system.

A common method of avoidance under both rules is to “job hop”. If an NRP fails to pay, a Deductions of Earnings Order (DEO) can be given to his employer, obliging him/her to take deductions from the NRP’s wages.  Many non-compliant NRP at this point will simply move onto a new job, requiring a trace procedure, which can take a considerable time.

To counteract this it is now possible for CSA staff to refer any “job hopping” NRP directly to Enforcement.  This is a fairly recent change to procedure and not all staff may be aware of it so it wouldn’t do any harm to mention it.

6.2  Account set-up  

Account set-up is usually a fairly quick procedure.  The object is to convert a weekly payment into an amount suitable for gathering at the NRP’s requested frequency (e.g. fortnightly or monthly).  The process for monthly pay can lead to some odd amounts for the first payment, but it is controlled by audit so cannot be challenged unless incorrect.

6.3  Debt Management  

It is the task of the debt manager to ensure the NRP makes regular payments and to pass them on to the appropriate PWCs.

7.  Your role

Contact from an MP or on his/her behalf serves to prioritise a case.  This may help to speed the handling of a case. Unfortunately due to staff shortages and problems with the new computer system, many complicated cases have to be escalated much higher up the complaints ladder before they will be dealt with.  So don’t presume because you have made a phone call or sent a letter that the case will be dealt with promptly. If further delays ensue, always ask about escalating the complaint.

This is particularly true of clerical cases.

Once a case is dealt with clerically, the process is much more time consuming and complaints often serve only to delay the process. Any member of staff answering a complaint has to stop processing a case to do so. However, there are times when escalating a complaint is they only way to ensure a case gets priority over other cases.

Having said that, one of the most helpful things might be to suggest a PWC or NRP to contact their case officer direct and establish a rapport with them.  CSA staff are only human and if they have a choice of two cases of equal priority, it is quite possible they will choose to help a customer they like. This, however, is less likely to work with any case running live on CS2 as the system usually allocates the work.

8.  Useful websites

The CSA web site has a lot of information about both new rules and old rules:

A handy tool for a new rule case is the maintenance calculator, but be warned it is only a guide and does not take all circumstances into account.  It is available at:

For a fairly balanced, if somewhat cynical, look at child support including the other side of the story read Barry Pearson’s:

Update – 13 March 2007
For information on the redesign of the Child Maintenance System, see the DWP website:

SW January 2005