Am I being unreasonable to remove my money from the joint account without saying anything?

Finally a man that wants to spend money on his children though! Would you consult him about spending on your joint child? You’re married so to me that makes a difference re joint spending.
is he spending money that’s supposed to be spent elsewhere? Is it resulting in financial hardship, is it resulting in no holidays etc?
do you maybe both need to just sit down and budget together? Maybe use a current account like starling or monzo that has savings pots? You could maybe have a specific pot for kids hobbies? So that you both understand where the money is going.
no I don’t think you’re being unreasonable for being cross for not being consulted, but I do think you’re both unreasonable for not having a proper conversation and agreed outcome about budgeting.

Tell him you're doing it and be prepared for the fallout. Your marriage is in trouble, I'm afraid.

I'd do it without discussion in case he does it and takes yours too.

It's not petty, it sounds like you've given him plenty of opportunities to discuss how the money is spent and he's ignored it.

He's being a cheeky fucker.

I don't think your husband should have to ask you before he spends money on his kids - but it should be his money not yours. So I vote yes - put only the bill money into the joint account and suggest he does the same then buy other things from your own accounts.

You will need to work out how to pay for food, your shared child, home maintenance etc fairly.

There's no way that a single joint account for everything can work where one person has children to support that are not their partner's

It can and it does work. I married a man with children from a previous marriage. They need supporting and I'm not bothered whether it's with my money or with his money. It's family money and those children are my family.

Tell him or else he will take money for his kids and Suddenly won't be enough left in account for household bills

Make your joint account just for your bills/household expenses, and then you both have your own money to spend as you want.

There’s no problem with the set up you’re suggesting - DH and I do the same, separate accounts for our salaries and we both transfer a set amount into our joint account. I don’t think I’d ever share access to my full salary to be honest. But it is unreasonable to change the current arrangement without telling him - you’re a grown up, you’re raising a child with this man, just have a conversation.

Tell him you're doing it, but obviously besides the bills you'll still need to jointly pay for food and expenses of your joint DC, so there'll need to be a discussion.

Tell him this.
I don't want to argue anymore about you spending your money on your children.
Your right I should it be dictating how you spend your money.
So I have arranged for my money to go into my own account and I will give you my share of the bills...
When he argues that you should still share an account. Tell him you agree , that you will share the bills account...
Keep repeating this to him, as if your agreeing .

Definitely open a new sole account @Pancakes78 Have your wages go in there and transfer your half out of the joint.

Present as a fait accompli. Shouldn't be too long before he recognizes his disposable income is rapidly disappearing.

Presumably their mum is actually paying for stuff for them, like food and heating and water…

Definitely have your wages paid into a different account and transfer your share of the bills.

This is what we do as I never signed up to pay everything for his DC but I think you need to tell him in advance even if just a week otherwise it’s quite childish to be honest

You'd be crazy not to

each partner has their own account, and puts into a joint account that pays household bills and the costs of their own shared child.

Exactly this.

If you do it without a discussion and an agreed plan, then what’s to stop him overdrawing the bills account or spending the money allocated on his children?

Have the discussion- without blame, try to stick to practicalities.

My adult DCs have their salary paid into their own accounts then transfer some for bills etc
Just point out they also have a mother funding their DCs lives.

YANBU. You have obviously tried discussing it like an adult but he is happy spending your disposable income as well as his own.

Keep it separate from now on.

I wouldn't have had a joint account in the first place. Now it's done though I'd let him know I'm doing it and just do it. I wouldn't keep it a secret.

I would do this, yes. If you've had the conversation and he still doesn't respect you enough to consult you then only by him having less (of your) money to spend will he realise that he needs to consider you.

It'll most probably only take a month or two for him to figure out how much of your money was being spent on his kids before he truly wants to have an honest conversation with you.

I'd do it, your step kids are taking money away from your child, they have 2 parents to fund them. You'll never get any thanks for it from anyone. I would tell him first and give him some notice though, no need to be an arsehole about it🤷‍♀️

While I would normally counsel having a conversation OP, I totally get how you feel, and if I'd lived for a long time with a DH who felt it was OK to spend MY money on HIS kids, without my consent, I would have no compunction about letting him find out how it feels to go to the account and find that money he expected to be there, isn't. After all, that's what he's doing to you, so go ahead and give him a taste of his own medicine, and when he asks why, just tell him that you've been trying to tell him for a long time that you've not been happy with him spending your money on his kids, without even discussing it with you, but he's not been prepared to listen, so doing it like this seemed the only way to make yourself heard. If he doesn't like it, then that's tough, he should have listened when you've tried to tell him. However, it does sound like there is a problem with communication generally in the relationship, if you can't get him to listen when you feel the need to discuss something as important as money.

There's no way that a single joint account for everything can work where one person has children to support that are not their partner's.

Maintenance and general expenses for those children should only be met by the partner who is their parent.

So each partner has their own account, and puts into a joint account that pays household bills and the costs of their own shared child.

Does he pay maintenance for them?