How should I divide up bills with partner?

[Kukoo]

So DP and I live together with my 3 DC (4 nights a week) and his DD (1 might one week, 2 nights the next).

Should the bills/mortgage be divided by 3 (me, my DC and DP - me paying for myself and my DC) or 50/50?

He doesn't think his DD should come into it as she's not here often enough.

Does his DC have her own room?

His DD should come into it, maybe not to the same extent as your DC as she's not there as much, but she's still there. Still needs a bed etc.

Sounds like he's being a bit of a tightwad.

So it's:

Gas & electric
Council tax
Water
Mortgage
Phone, Internet & tv

Does one of you earn significantly more than the other?

I'm a sahm and he is a tradesman so earns quite a bit more than me.

50:50
Because you are a partnership.
If he doesn't like that. - then it's not a partnership. He's not a lodger

So how were you paying your bills before you moved in? Do you have another income stream?

It is bloody complicated!

Put all your money for bills etc into a joint account. Split what's left between you. You're supposed to be a partnership.

Don't live with someone & be a SAHM unless you have another income.

We get working tax credits and child tax credits so I will have to pay my share out of that. I own the house so have money in equity but obviously it's all tied up.

We go 50/50 on food shopping

I'd say 50/50 on bills & potentially food is the only thing you pay extra for as you're feeding 4 mouths whereas he's only feeding 1 ( or 2 occasionally with his DD).

The bills re electric, gas, rent, TV, council tax etc don't change because of the children ( their impact would be minimal) - food is the only variable that I can see.

We get £55 working tax credits a week which are for 'me'.

If you're going to live together you're all a family. None of this my child is here X amount of time. Ignore the children they are now your joint responsibility 50/50 for adults

I earn less than dp and my child isn't his. He pays big bills (mortgage, utilities and his own direct debits) and I pay council tax, tv license, food, treats my own direct debits like phone and car.

What about if we spilt bills 50/50 then mortgage into 3?

Why would you split the mortgage anything other than 50/50? It doesn't go up or down depending on the number of children living there.

My DP has recently moved in with me and DS.

I earn a bit more than him, DS is not his.
DS is still in nursery so I have a nursery bill of nearly 1k which is by far the biggest expense.

I also have rent - 725, council tax, bills, Internet, food.

I lost £400 in TC when he moved in.

He pays 525 and then I do the rest. That's way more than half rent and a decent contribution to bills. I didn't want full blown 50/50 because it didn't feel fair.

I think there are lots of variables to consider

Are their any legal issues from allowing him to pay towards the mortgage ?

And did you lose benefits when he moved in ? What about coucil tax ?

So you own the house but there's a mortgage on it? How is that being paid for now and how was it paid for before he moved in?

What is his suggestion?

Are you worse off yourself now that he's moved in, in terms of tax credits etc?

Do you share any children?

I wouldn't pay towards any mortgage that didn't have my name on it.

How were you paying it before he moved in?

How are you supposed to pay half the bills on £55 a week?

If he contributes to the mortgage he might have a legal entitlement to some of the value of the house. What would happen then if you split up in 3yrs time? You could speak to someone in Citizens Advice centre and find out about the Mortgage part of it. You have 3 kids and no other income so you need that house to be yours outright no matter what happens, with no one else being able to have a claim on it.
It doesn't sound like you are living together very long. So best to get good advice now before stuff gets agreed.

OP, what's the full picture please?