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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:
ImImmortalNowBabyDoll · 09/06/2026 17:31

ThisOldThang · 09/06/2026 17:15

I don't understand why CMS was due for the eldest son, but no CMS was due for the younger son. Why weren't both children/cases found to be either CMS due or no CMS due?

I'm going to take a wild guess that in actual fact her ex has been having the eldest more than 50% of the time, OP has been giving us her "version" of the facts and conveniently rounded up the times.

BudgetBuster · 09/06/2026 17:49

ThisOldThang · 09/06/2026 17:15

I don't understand why CMS was due for the eldest son, but no CMS was due for the younger son. Why weren't both children/cases found to be either CMS due or no CMS due?

They had different access arrangements for each child

JustAnotherWhinger · 09/06/2026 17:49

ThisOldThang · 09/06/2026 17:15

I don't understand why CMS was due for the eldest son, but no CMS was due for the younger son. Why weren't both children/cases found to be either CMS due or no CMS due?

CMS must have found that the youngest was 50:50, but the eldest wasn’t. That’s the only reason it would work that way.

MumOryLane · 09/06/2026 19:55

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.

Out of curiosity, what differed in your case to ProlongedAffair's that made you think there'd be a different outcome?

EwwPeople · 09/06/2026 20:00

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.

It’s not a twist is it? You’ve been warned numerous times that this is a possible/likely outcome. Was it worth it?

fixatedplanet · 09/06/2026 20:07

ThisOldThang · 09/06/2026 17:15

I don't understand why CMS was due for the eldest son, but no CMS was due for the younger son. Why weren't both children/cases found to be either CMS due or no CMS due?

CMS split the children once he got the child benefit for the older one, the care arrangement is identical. He then successfully challenged the one he was not getting child benefit for and got it recognised as equal day to day care, whilst the one he was getting child benefit for remained with him as the primary carer because I did not provide evidence as I was in a bit of a mess as to where this was going to end up. CMS could have been a bit more sensible here and treated the children the same, but they didn’t.

OP posts:
JustAnotherWhinger · 09/06/2026 20:17

fixatedplanet · 09/06/2026 20:07

CMS split the children once he got the child benefit for the older one, the care arrangement is identical. He then successfully challenged the one he was not getting child benefit for and got it recognised as equal day to day care, whilst the one he was getting child benefit for remained with him as the primary carer because I did not provide evidence as I was in a bit of a mess as to where this was going to end up. CMS could have been a bit more sensible here and treated the children the same, but they didn’t.

CMS don’t have the authority to treat the children the same just because, they legally had to go by the evidence provided.

If you still have that listed against you be very careful that it is closed fully and properly.

MoFadaCromulent · 09/06/2026 20:44
Animated GIF

CMS could have been a bit more sensible here

BudgetBuster · 09/06/2026 22:34

MoFadaCromulent · 09/06/2026 20:44

CMS could have been a bit more sensible here

Of all the people who could have been more sensible... I don't think it was CMS 😂

Velumental · 09/06/2026 23:36

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.

Literally EXACTLY what everyone on this thread told you would happen. How is that a plot twist? It's the expected outcome

Velumental · 09/06/2026 23:37

fixatedplanet · 09/06/2026 20:07

CMS split the children once he got the child benefit for the older one, the care arrangement is identical. He then successfully challenged the one he was not getting child benefit for and got it recognised as equal day to day care, whilst the one he was getting child benefit for remained with him as the primary carer because I did not provide evidence as I was in a bit of a mess as to where this was going to end up. CMS could have been a bit more sensible here and treated the children the same, but they didn’t.

Di you not feel a bit of an idiot? All that wasted effort and loss of goodwill

harriethoyle · 10/06/2026 10:51

Oh my God. I could never have seen that plot twist coming. Never. My flabber is GHASTED!!

GargoylesofBeelzebub · 10/06/2026 14:09

You have been incredibly lucky that your ex seems like a far more reasonable person than you are. You were absolutely crazy to do what you did. You could have completely destroyed your co parenting relationship.

PullyDog · 12/06/2026 22:59

Respect to you for coming back and being honest about the outcome.

You really should have listened to all the advice but it is what it is.

How do you feel?

soupbucket · 18/06/2026 11:27

thanks for the update OP, I hope this thread might help others in a similar situation

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