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Challenging what the CMS says you should get

This advice applies to Wales

The Child Maintenance Service (CMS) will write to tell you how much maintenance you should get. If you’re not sure how they worked that out, you can use the calculator on GOV.UK or talk to an adviser

You can ask the CMS to look again at their decision on how much you’ll get if:

  • you think their decision is wrong

  • your circumstances have changed - like if your child stops staying overnight with the paying parent 

  • you think the paying parent has income or assets which the CMS hasn’t taken into account

If you think the CMS decision is wrong

You can ask the CMS to look at their decision again at any time if it’s wrong because they made an ‘official error’. This means they either:

  • made a mistake

  • based their decision on a mistake by the Department for Work and Pensions (DWP) or HM Revenue and Customs (HMRC)

Asking for mandatory reconsideration 

If you think the decision is wrong, you can ask the CMS to look at their decision again. This is called asking for a ‘mandatory reconsideration’. You should say why you think the decision is wrong. 

You can call the CMS or write to them. It’s best to ask in writing so that you have a copy of your letter or email. You’ll need the 12-digit reference number on the letter saying how much you’ll get. If you can’t find your reference number, you’ll need to give:

  • your name

  • your address

  • the name and date of birth of the child you’re paying maintenance for

The contact details are:

Child Maintenance Service

Child Maintenance Service 21

Mail Handling Site A

Wolverhampton

WV98 2BU

Telephone: 0800 171 2345

Relay UK - if you can't hear or speak on the phone, you can type what you want to say: 18001 then 0800 232 1975

You can use Relay UK with an app or a textphone. There’s no extra charge to use it. Find out how to use Relay UK on the Relay UK website.

Monday to Friday, 8am to 7.30pm

Saturday, 9am to 4.30pm

Calls are free from mobiles and landlines.

If you’re sending a letter, ask the Post Office for free proof of postage - you might need to show when you sent it. 

If you can show the calculation is wrong, you should send a copy of that too. 

If you call, make a note of when you called, who you spoke to and what they told you. Follow your call up with a letter or email so you have a written record. 

Ask within 1 month of the decision

Check the date on your decision letter. You need to ask for a mandatory reconsideration within 1 month of the date on that letter. Explain why you disagree with the decision. 

If you’re close to the 1 month deadline, call the number at the top of your decision letter instead of writing. 

If you miss the 1 month deadline

It's still worth asking for a mandatory reconsideration.

You’ll need to explain why your request is late - for example if you were ill or dealing with difficult personal circumstances. You don’t need to have proof of why it’s late, but if you do you should send it with the form. For example, if you were in hospital, coping with a bereavement or had an emergency at home.

You’ll also need to explain why you disagree with the decision. 

The CMS can refuse your application if it's late. You can still appeal to a tribunal if you apply within 13 months of the date on your decision letter.

Getting a decision - mandatory reconsideration notice

Once the CMS has made a decision, you’ll get a letter with the outcome. That letter is called a ‘mandatory reconsideration notice’. Keep it safe - you’ll need it if you want to appeal. You’ll get 2 copies of the notice so you can send one with your appeal. 

If the CMS changes its decision, it will change the amount you get and backdate that to the date of their original decision. 

If it doesn’t change its decision, you’ll keep getting the amount the CMS originally said you’d get. 

Appealing a decision after a mandatory reconsideration

If you’re unhappy with the result of the mandatory reconsideration, you can appeal to an independent tribunal. It’s free and you don’t need a lawyer. 

Coronavirus - if you’re appealing a child maintenance decision to the tribunal

If possible, a tribunal judge will assess your case without a hearing. Instead they’ll make a decision based only on the documents.

Some tribunals have closed so it’s a good idea to check where you should send your documents - you can find contact details for your tribunal on GOV.UK.

Send any evidence you have as soon as possible - for example, financial documents like bank statements.

If the judge assesses your case based on the documents, they’ll send you a ‘provisional decision’. If you don’t agree with the provisional decision, tell the tribunal you want a hearing instead.

If there has to be a hearing, the tribunal might suggest a phone call or video conference.

Tell the tribunal as soon as possible if you will find it difficult to have a remote hearing. For example, tell them if you don’t have the equipment for a conference call. You can find out what happens at a remote hearing on GOV.UK.

You must appeal within 1 month of the date of the mandatory reconsideration notice. If you miss that deadline, you might be able to ask for a late appeal. You must give as much detail as possible for why your late appeal should be allowed.

You can read more about making an appeal on GOV.UK. 

The time limit for a late appeal is 13 months from the date of mandatory reconsideration notice. In very exceptional circumstances, the tribunal might extend the 13-month time limit. For example if you didn’t get a copy of the notice.

If you don’t want your former partner to know where you live

You can ask the tribunal to keep your address confidential. If you need to do this, tell the tribunal when you send in your appeal.

If your circumstances change

Coronavirus - if your circumstances have changed

At the moment, you might have to report a change of circumstances in a different way - even if the change isn’t because of coronavirus. 

You can find out how to report a change of circumstances on GOV.UK.

Every year the CMS will review how much you get. When they do, they might say you have to pay a different amount. 

If your circumstances change between reviews, you can ask the CMS to look again at how much you get. For example, if the child stops staying overnight with the paying parent. 

There are some changes you must report to the CMS. 

Check what changes you need to report

You could be fined up to £1,000 if you don’t report certain changes to the CMS. You must tell the CMS if:

  • your child no longer counts as a child, for example, because they’ve left approved education - check what’s approved education on GOV.UK

  • you stop having day-to-day care of the child you’re getting maintenance for

  • you, your child or the paying parent move abroad 

  • your child is adopted by someone else

  • your child has died

  • the paying parent has died

You don’t need to report a change until it's happened. If the change is likely to mean you get more maintenance, you should report it as soon as you can. If the CMS changes how much you get, that change will usually take effect from the date you reported it. 

Check how to report a change

You can report changes through your online account or by calling the CMS. You can check what you can report by phone and online on GOV.UK.

You’ll need your 12-digit reference number when you call - you can find this on letters from the CMS. If you can’t find your reference number, you’ll need to give:

  • your name

  • your address

  • the name and date of birth of the child you’re getting maintenance for

Child Maintenance Service

Telephone: 0800 171 2345

Relay UK - if you can't hear or speak on the phone, you can type what you want to say: 18001 then 0800 232 1975

You can use Relay UK with an app or a textphone. There’s no extra charge to use it. Find out how to use Relay UK on the Relay UK website.

Monday to Friday, 8am to 7.30pm

Saturday, 9am to 4.30pm

Calls are free from mobiles and landlines.

If the paying parent has income the CMS hasn’t taken into account - asking for a variation

The CMS uses the paying parent’s gross income when calculating how much maintenance you get. Gross income is income before tax and national insurance have been deducted.

If you think they’ve got income or assets which the CMS doesn’t know about, you can ask the CMS to take that into account and recalculate what you get. This is called asking for a ‘variation’. 

You might have to give the CMS detailed information about the extra income or assets. The CMS will ask HM Revenue and Customs (HMRC) for information. HMRC will only have it if the paying parent has reported the income or assets to them. 

Check when you can’t get a variation

The CMS won’t agree to a variation if:

  • the parent paying maintenance is getting income-based Jobseeker’s Allowance, Income Support or income-related Employment and Support Allowance

  • the parent paying maintenance is getting Universal Credit and isn’t earning anything

  • you’re getting a default rate of maintenance because the CMS didn’t have enough information to make a calculation

Even if none of these things apply, the CMS will only agree to a variation if they think it would be fair. They can look at the following things to decide if it’s fair:

  • the welfare of any child who might be affected

  • if the paying parent might give up their job if they had to pay more

The CMS ignores any income the paying parent has if it's over £3,000 a week. If you want income over £3,000 taken into account, you can't ask for a variation to get more maintenance. You'll have to go to court instead. 

Check when you can get a variation

If the CMS agrees to a variation, they can add any extra income to the paying parent’s income and make a new calculation.

This type of variation is called an ‘additional income variation’ and covers:

  • unearned income - like income from rent

  • earned income - like pay from a second job

  • income which has been moved to reduce how much the paying parent has - this is called ‘diverted income’

  • income from assets worth over £31,250, for example a second home or shares - this is called ‘notional income’

Unearned income

You can apply for a variation if the parent paying maintenance has taxable income of more than £2,500 a year from any of the following sources:

  • property - like rental income

  • savings, investments and interest on bank accounts

  • other income - like casual earnings from one-off jobs

Diverted income

You can apply for a variation if the parent paying maintenance might be limiting how much income they have by:

  • giving it to someone else

  • diverting the income so it can’t be included in the maintenance calculation - like keeping profits in a company rather than taking a wage

  • paying too much into their pension

If the paying parent pays £7 a week or nothing but has weekly income of £100 or more

In some cases, the paying parent might only be asked to pay £7 a week. This is called the ‘flat rate’. They’ll pay this if they’re on certain benefits or have income of less than £100 a week. 

They might not be asked to pay anything at all if they’re in prison, a care home or under 16. People who aren’t asked to pay anything are said to be on the ‘nil rate’.

You can ask for a variation if you don’t think they should be on the flat rate or the nil rate because their income before tax is £100 or more.

Applying for a variation

You can ask for a variation before or after the Child Maintenance Service (CMS) has calculated how much you should get. 

You can call the CMS or write to them. It’s best to ask in writing so that you have a copy of your letter or email. You’ll need the 12-digit reference number on the letter saying how much you’ll get. If you can’t find your reference number, you’ll need to give:

  • your name

  • your address

  • the name and date of birth of the child you’re paying maintenance for

The contact details are:

Child Maintenance Service

Child Maintenance Service 21

Mail Handling Site A

Wolverhampton

WV98 2BU

Telephone: 0800 171 2345

Relay UK - if you can't hear or speak on the phone, you can type what you want to say: 18001 then 0800 232 1975

You can use Relay UK with an app or a textphone. There’s no extra charge to use it. Find out how to use Relay UK on the Relay UK website.

Monday to Friday, 8am to 7.30pm

Saturday, 9am to 4.30pm

Calls are free from mobiles and landlines.

If you’re sending a letter, ask the Post Office for free proof of postage - you might need to show when you sent it. 

If you call, make a note of when you called, who you spoke to and what they tell you. Follow your call up with a letter or email so you have a written record.

The CMS might ask you for more information. If they do, you should send it to them within 14 days. 

If the CMS accepts your application for a variation, they will tell the paying parent. The paying parent has 14 days to say if they disagree. They could also ask for a variation - check what they can ask for a variation for

If the paying parent disagrees, you have 14 days to comment on anything they’ve said. 

Once the CMS has considered all the information, it might change what you get.

Example

Marcus is self-employed and has told HMRC he earns £200 a week. He has 1 child with his former partner, Tara. The child doesn’t stay overnight with him. He lives on his own.

The CMS has told him to pay 12% of his weekly income in maintenance. So Marcus pays £24 a week (12% of £200 is £24).

Tara believes Marcus is moving £400 a week to his company. She applies for a variation. 

The CMS eventually accepts this and adds the £400 to the £200 Marcus said he earns (£400 + £200 = £600). Marcus now has to pay 12% of £600 in maintenance. 12% of £600 is £72, so Tara’s child maintenance is increased to £72 a week.

Getting the new amount

When you’ll start getting the new amount depends on the reason for the variation and when you applied for it.

If the reason for the variation existed when the CMS calculated maintenance

You’ll get the new amount from the date the CMS calculated maintenance. 

The CMS can only do this if you tell them either:

  • before they make the calculation

  • within 30 days of being told of the amount of the calculation

If you apply later than that, the variation will start from the date you told the CMS you wanted to apply for a variation.

Example 

Tara has evidence Marcus started moving his income just before she made her application for child maintenance. 

She asked for the variation as soon as she got the letter from the CMS saying how much she would get.

The variation is backdated to the start of her claim.

If the reason for the variation happened after your first maintenance payment

You’ll get the new amount from the date you asked the CMS for a variation. For example, if you tell the CMS the paying parent has unearned income, the variation will start from the date you told them. 

If you want to complain about the CMS

If you’re unhappy with the service you’ve received from the CMS rather than with a decision they made, you can make a complaint. Read more about complaining about the CMS

 

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