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Ex disputing CMS and making rival Child Benefit claim in 50/50 care

465 replies

fixatedplanet · 22/03/2026 14:34

Hi all,

I’m really struggling with this and could do with some advice.

We’ve had a proper 50/50 week-on/week-off arrangement for the last 4.5 years. The boys (14 and 11) split their time equally between us week on/week off and we’ve always split the costs of shared things 50/50. He does his bit when they’re with him and I do mine. It has been working fine but....

The issue is income. I earn around £60k and he earns well over the £156k threshold. Because of that, even though it’s 50/50, I applied to CMS for child maintenance so he pays his fair share (it comes out at the maximum rate, around £800 a month which is a 50% discount as he has them 7 nights out of 14). I thought that was reasonable as his salary is much higher and he should pay more than half.

He immediately challenged it with a Mandatory Reconsideration, which was rejected because I receive the Child Benefit (he gave it up due to the high income charge and then during divorce said I could have it which only seemed fair). Now he’s put in a rival Child Benefit claim for one of the children AND lodged a tribunal appeal with the CMS. He’s basically trying to get out of paying anything through CMS and I could lose some of the child benefit now!!!

We are completely 50/50. He does everything on his time and I do everything on mine. But because he earns more, he should contribute more and CMS should sort this I would have thought, I should not have to go to a tribunal.I have started to gather evidence to try and show that I do more so it gives me a good chance at the tribunal and I guess he is doing the same now. I am going to get a barrister to help out at the tribunal to try and prove I do more but he does stuff too so not sure if that will help me.

I’m worried he might actually get the Child Benefit (even though he can’t claim it himself because of the high income charge) and that the tribunal might side with him. Does he have any chance of winning that? It just doesn’t feel fair because he earns much more than me even though we share all the care equally. He did offer to cover all of the shared costs but I have said no and decided to go down the CMS route as that will be more money than simply covering the shared costs.

Has anyone been through this? Can he really do the rival Child Benefit thing and what are his chances? I guess he has lots of evidence to show that we share care equally and have done for several years but he cannot even claim it so I would miss out! And what are the chances at tribunal? Surely they will see my side of things? He has started to pay me the £800 a month now so I have had a few months payment so far so that is good at least but I am worried I might lose it or be told to give it back.

Thanks in advance.

OP posts:
EmeraldShamrock000 · 09/06/2026 06:49

fixatedplanet · 08/06/2026 21:44

In a twist I wasn't expecting, once my ex managed to get Child Benefit for my older son, he was then able to open a CMS case against me. CMS assessed that I should pay him child maintenance for our older son, so I was ordered to pay £260 per month.

He then continued to challenge the position regarding our younger son and argued that care was shared equally on a day-to-day basis. CMS accepted that argument and determined that no child maintenance was payable by either party for him.

The end result was that I wasn't entitled to receive any child maintenance at all, and instead I had a liability to pay maintenance for my older son.

After all of that, we've discussed it between ourselves and agreed to close the CMS case and move to a private arrangement instead.

It's certainly not where I expected things to end up when this all started. In the end I received two months of child maintenance payments from him before everything changed. I still don't know whether CMS will seek to recover those payments or whether they'll be left as they are.

Not the outcome I anticipated, I am sure a few of you will be delighted no doubt.

That sucks. It’s a pity you didn’t ask for advice before bringing this forward. There is no maintenance required in a 50/50 co-parent relationship.
Can you take on an extra job in the evenings to bulk your income.

JustMyView13 · 09/06/2026 06:15

ImImmortalNowBabyDoll · 08/06/2026 23:23

How someone can ask what's going to happen, be told what is going to happen, carry on on their current path regardless and then be shocked when it happens is totally beyond the realms of my comprehension.

I agree. But OP said they were using ChatGPT so this is probably a classic case of believing the output which had a bias input.

ChatGPT doesn’t replace good legal advice, and doesn’t understand the nuance that people who have actually experienced legal processes, are able to (and did) share.

Ex sounds very reasonable if they’re willing to play your (OP’s) games with the CMS, and then revert to a private arrangement after OP lost.

ImImmortalNowBabyDoll · 08/06/2026 23:23

JustAnotherWhinger · 08/06/2026 23:02

Hardly a twist when you’d been warned by multiple people, including a poster in a similar position, that this is exactly what would happen.

Very lucky for you that you have an ex that is more focussed on the preservation of your Co-parenting relationship than financial gain or one upmanship

good luck with it all

How someone can ask what's going to happen, be told what is going to happen, carry on on their current path regardless and then be shocked when it happens is totally beyond the realms of my comprehension.

JustAnotherWhinger · 08/06/2026 23:02

fixatedplanet · 08/06/2026 21:44

In a twist I wasn't expecting, once my ex managed to get Child Benefit for my older son, he was then able to open a CMS case against me. CMS assessed that I should pay him child maintenance for our older son, so I was ordered to pay £260 per month.

He then continued to challenge the position regarding our younger son and argued that care was shared equally on a day-to-day basis. CMS accepted that argument and determined that no child maintenance was payable by either party for him.

The end result was that I wasn't entitled to receive any child maintenance at all, and instead I had a liability to pay maintenance for my older son.

After all of that, we've discussed it between ourselves and agreed to close the CMS case and move to a private arrangement instead.

It's certainly not where I expected things to end up when this all started. In the end I received two months of child maintenance payments from him before everything changed. I still don't know whether CMS will seek to recover those payments or whether they'll be left as they are.

Not the outcome I anticipated, I am sure a few of you will be delighted no doubt.

Hardly a twist when you’d been warned by multiple people, including a poster in a similar position, that this is exactly what would happen.

Very lucky for you that you have an ex that is more focussed on the preservation of your Co-parenting relationship than financial gain or one upmanship

good luck with it all

MoFadaCromulent · 08/06/2026 22:41

You're lucky your ex is a much better person than you who cares about co-parenting and the knock effect for his kids

ProlongedAffair · 08/06/2026 22:40

My kids hate me so count yourself lucky.

ElectricLegs · 08/06/2026 22:36

It's only money. I am glad that the parents are still getting on. That was the most important thing for the kids.

ImImmortalNowBabyDoll · 08/06/2026 22:05

fixatedplanet · 08/06/2026 21:44

In a twist I wasn't expecting, once my ex managed to get Child Benefit for my older son, he was then able to open a CMS case against me. CMS assessed that I should pay him child maintenance for our older son, so I was ordered to pay £260 per month.

He then continued to challenge the position regarding our younger son and argued that care was shared equally on a day-to-day basis. CMS accepted that argument and determined that no child maintenance was payable by either party for him.

The end result was that I wasn't entitled to receive any child maintenance at all, and instead I had a liability to pay maintenance for my older son.

After all of that, we've discussed it between ourselves and agreed to close the CMS case and move to a private arrangement instead.

It's certainly not where I expected things to end up when this all started. In the end I received two months of child maintenance payments from him before everything changed. I still don't know whether CMS will seek to recover those payments or whether they'll be left as they are.

Not the outcome I anticipated, I am sure a few of you will be delighted no doubt.

You were warned.

Laura95167 · 08/06/2026 22:03

fixatedplanet · 08/06/2026 21:44

In a twist I wasn't expecting, once my ex managed to get Child Benefit for my older son, he was then able to open a CMS case against me. CMS assessed that I should pay him child maintenance for our older son, so I was ordered to pay £260 per month.

He then continued to challenge the position regarding our younger son and argued that care was shared equally on a day-to-day basis. CMS accepted that argument and determined that no child maintenance was payable by either party for him.

The end result was that I wasn't entitled to receive any child maintenance at all, and instead I had a liability to pay maintenance for my older son.

After all of that, we've discussed it between ourselves and agreed to close the CMS case and move to a private arrangement instead.

It's certainly not where I expected things to end up when this all started. In the end I received two months of child maintenance payments from him before everything changed. I still don't know whether CMS will seek to recover those payments or whether they'll be left as they are.

Not the outcome I anticipated, I am sure a few of you will be delighted no doubt.

Not delighted. Although i did find your initial decision to go down CMS route because you believed youd get more money, grabby and entitled.

But we did say this would happen. I cant see how this was a "twist" after almost all posters advised you. It wasnt even about whether we agreed with your position (i didnt) just thats the usual consequences of this process. And I think, especially compared to @ProlongedAffair's situation, youve been very lucky to come out of this in such an amicable and affordable way.

Im glad youve managed to keep a good coparent situation. Best of luck

BMW58 · 08/06/2026 22:02

Blimey OP you were warned so much, but kudos to you for updating here

BudgetBuster · 08/06/2026 21:58

Thechaseison71 · 08/06/2026 21:50

Didn't another poster tell you thiswould happen?

17 pages of posters told her 🙄

Thechaseison71 · 08/06/2026 21:50

fixatedplanet · 08/06/2026 21:44

In a twist I wasn't expecting, once my ex managed to get Child Benefit for my older son, he was then able to open a CMS case against me. CMS assessed that I should pay him child maintenance for our older son, so I was ordered to pay £260 per month.

He then continued to challenge the position regarding our younger son and argued that care was shared equally on a day-to-day basis. CMS accepted that argument and determined that no child maintenance was payable by either party for him.

The end result was that I wasn't entitled to receive any child maintenance at all, and instead I had a liability to pay maintenance for my older son.

After all of that, we've discussed it between ourselves and agreed to close the CMS case and move to a private arrangement instead.

It's certainly not where I expected things to end up when this all started. In the end I received two months of child maintenance payments from him before everything changed. I still don't know whether CMS will seek to recover those payments or whether they'll be left as they are.

Not the outcome I anticipated, I am sure a few of you will be delighted no doubt.

Didn't another poster tell you thiswould happen?

SoggyTissue · 08/06/2026 21:50

🙄 next time, listen.

randomchap · 08/06/2026 21:49

So basically exactly what you were told would happen.

fixatedplanet · 08/06/2026 21:44

In a twist I wasn't expecting, once my ex managed to get Child Benefit for my older son, he was then able to open a CMS case against me. CMS assessed that I should pay him child maintenance for our older son, so I was ordered to pay £260 per month.

He then continued to challenge the position regarding our younger son and argued that care was shared equally on a day-to-day basis. CMS accepted that argument and determined that no child maintenance was payable by either party for him.

The end result was that I wasn't entitled to receive any child maintenance at all, and instead I had a liability to pay maintenance for my older son.

After all of that, we've discussed it between ourselves and agreed to close the CMS case and move to a private arrangement instead.

It's certainly not where I expected things to end up when this all started. In the end I received two months of child maintenance payments from him before everything changed. I still don't know whether CMS will seek to recover those payments or whether they'll be left as they are.

Not the outcome I anticipated, I am sure a few of you will be delighted no doubt.

OP posts:
soupbucket · 27/04/2026 10:03

Appreciate the update OP

JustAnotherWhinger · 27/04/2026 09:08

Haystackhunting · 26/04/2026 09:25

I do particularly enjoy the narrative though now we’ve moved away from she’ll never get a penny she’s not legally entitled. It’s morally wrong too.
She has in fact being entirely vindicated.
And now we’re concerned about whether he’ll be all upset and he won’t be civil
And the implication that that’ll be her fault as well
What a bunch of clowns

No, she hasn’t. The 50/50 aspect hasn’t been dealt with yet.

Once that goes to tribunal she’ll still get nothing.

Atm there are just two standard cases set up. That system doesn’t allow for the 50/50 to be recognised. It doesn’t remotely mean the current position of each paying for one child will stand going forward.

JustAnotherWhinger · 27/04/2026 09:06

ImImmortalNowBabyDoll · 26/04/2026 10:52

If he takes it to tribunal it will be reduced to nil payment. It's really annoying that CMS doesn't know their own rules.

The CMS staff (the decent ones) find it incredibly frustrating, but they have no choice but to use the CB = entitled to CMS formula.

The system is cheap and poor and doesn’t allow for staff to do anything other than follow the very basic formula. It can be incredibly frustrating when you get a case that is outwith the simple set up of one parent having majority care and claiming accordingly.

The fact the calculator is so inaccurate, especially with 50:50 cases, causes so many arguments and issues. Its really really poor that its still on the site and the warnings that its a very very very rough estimate that depends on a lot of factors are not clear enough.

ThisOldThang · 26/04/2026 22:49

Haystackhunting · 26/04/2026 09:25

I do particularly enjoy the narrative though now we’ve moved away from she’ll never get a penny she’s not legally entitled. It’s morally wrong too.
She has in fact being entirely vindicated.
And now we’re concerned about whether he’ll be all upset and he won’t be civil
And the implication that that’ll be her fault as well
What a bunch of clowns

I don't think that's the current situation.

He's now got child benefit for one child and they've immediately reduced his payments based purely upon the child benefit. They haven't yet addressed the 50:50 care arrangement. He can now use the child benefit to support his claim. It will likely be determined that no CMS is due to either party and the OP will need to repay the money she's claimed.

dadtoateen · 26/04/2026 19:33

ThatCyanCat · 26/04/2026 09:25

fuck that and if the kids can’t see it when they’re older more for them, not the kind of kids I’d want in my life anyway

Wow.

Recon this is the only thing we have agreed on 🤣

dadtoateen · 26/04/2026 19:31

Haystackhunting · 26/04/2026 09:20

So yet again, women have to take the Financial hit and take it up the arse for the sake of civility whereas men can’t just do the right thing in the first place
For the sake of civility
fuck that and if the kids can’t see it when they’re older more for them, not the kind of kids I’d want in my life anyway

Edited

Have you actually read the thread? He was paying way over what he had to.
the mum wanted more cause she wanted holidays etc.
then it all went tits up cause she now only gets what she deserves.
So no, your rant is complete bollocks. The MAN took a massive hit in this and probably many other men.
Then you attack the kids. Wow you seem so lovely 😊

kittensinthekitchen · 26/04/2026 18:06

.

Kim Kardashian Horror GIF by AHS
Madarch · 26/04/2026 12:17

@Haystackhunting I'm genuinely concerned for your wellbeing. You've clearly had a shit time and seem to be carrying a fuck ton of anger. Are you getting any kind of support?
You sound pretty fucked up.

Madarch · 26/04/2026 12:14

Haystackhunting · 26/04/2026 08:16

Good well done for enforcing your legal rights.
Who gives a shit about how the coparenting relationship is? You are divorced from these people. They are no longer your friends.
Even if they pretend to be, they wouldn’t piss on you if you were on fire

Smooth co-parenting is not for the benefit of the parents. It makes for happy kids and models how to manage break-ups well so as not to traumatise the next generation

BudgetBuster · 26/04/2026 11:42

randomchap · 26/04/2026 11:16

If that's what the tribunal decides, will OP be told to pay back what he paid before it got to tribunal?

If the father enters a back claim, yes. Most likely what will happen is the backpack will be offset by his 50% of future shared costs. So essentially she would be responsible for 100% of shared costs going forward until such point the debt is cleared.... given the kids ages that might be after one or both turn 18!