AIBU to advise my daughter that she'd be daft to not put her name on house deeds?

Sharing the bills, fine, as long as she is not helping to pay the mortgage or house renovations. If she's not on the deeds then she is an informal lodger with no rights at all and her money should go into her own savings account not into the house.

If she is helping to pay off the mortgage or pay for renovations decoration etc then she and DP need a signed legal agreement that dictates how much of the value goes to her when the house is sold. I had one with DH before we were married, the amount changed over the years to reflect that I put up the deposit while DP paid more of the mortgage so I got my deposit back plus a decreasing share of the reversion. And the agreement was torn up when we married.

Your DD (and her DP) really need to consult a solicitor.

I assumed "bills" included mortgage, but if not then no she shouldn't be on the deeds, if yes then she should.

Mortgage companies wont allow someone on the deeds if they're not also part of the mortgage

Is she going to be part of the mortgage, is the mortgage application a joint one so that its also her debt? She is buying the house jointly with him?

You say your dd “is planning on buying a house with her bf”….is she actually involved in the buying of the house ie. getting a mortgage, paying towards the deposit and all the legal fees, or do you mean her boyfriend is buying a house and she’s going to be living with him in his new house and contributing to bills, food, day to day expenses that she would contribute if she were renting?

Because if it’s the first then of course she should be on the deeds but if it’s the second then I think you’re taking advantage of her boyfriend and hoping to better your dd’s situation at someone else’s expense and hard work. And I say that as someone who was in your DD’s position.

If she is only sharing the bills, then no way should her name be on the deeds. If I were his parents,

I would be refusing to give him the money if his girlfriend insisted on it. Let her buy her own house, she's only 20, what an example you're setting her!

If she's not on the application for the mortgage then her name doesn't go on the deeds.

Simple.

If she's paying part of the mortgage absolutely otherwise she should be saving that money for her own place.

It depends on if she’s contributing to the mortgage as well.

DH and I (back in the day) bought out first flat with a deposit from his parents. However we both our incomes were required to get the mortgage so we did Tenants in Common.

If he’s buying without her input then she doesn’t go on the deeds.

If she’s not contributing to the deposit, going on the mortgage, and paying the mortgage, I wouldn’t be putting her on the deeds.

Be careful.

She’s only 20.

How long have they lived together so far?

It is more than a financial decision to put your name on the deeds. She is also committing herself further to her boyfriend.

In theory she and he could sell the house but in practice it makes splitting up harder.

I did this myself at 22 (under the advice of my mother) and it really did put me in the mindset of “well this is it then”.

I would make sure they set up sort of tenancy agreement, where she is paying what a tenant would to rent. I would also make sure she is making her own savings and pension contributions.

They can do this with a mind to reviewing it in a year or two when they’ve spent more time together as a couple.

Your daughter will need to pay bills (she would be doing this if he was buying or if they were renting). He is young, buying a house with parents money - your daughter needs to pay her share fairly (in what she would usually pay to rent etc0 and then enjoy living with her boyfriend. There is no way if it was my son would I be encouraging at that age that they buy a house together , especially if he is paying for it outright! Children, marriage etc change things, and then my advice would be different - not two young people setting out in life together

They can get a declaration of trust to protect his deposit. Will she be paying towards the mortgage or just the bills ?
I imagine his parents will be wanting to protect their son's deposit.

I get your thinking but no, she needs to finance her own property and yes I would say the same in reverse

He needs to keep her off the deeds

Is she paying half the mortgage? Or is he buying it outright?

I’m a she putting anything into the deposit or paying towards the mortgage? If not then he’d be stupid to out her on the house deeds, especially after such a short relationship and their age.

What is your dd putting into the purchase and will they be splitting the mortgage or just the bills?

This. If it is being brought with his money only he buys in his name. If I was him I wouldn’t put her on the deeds. She saves and buys her own house.

TBH I think your DD should not get involed in this at all. It has disaster written all over it.