Which parent’s last name to give baby?

[UnexpectedCurveBall]

My daughter told us last week she was pregnant. Unplanned and unexpected. She and her boyfriend are only 18. He works, she is coming to the end of her first year at uni (we’re helping her plan for how she can finish her degree with a hybrid of online before going back to in person). They want to keep the baby.

My question is, whose last name would you give the baby? Hers or his?

I was going to type a whole background and explanation to my thoughts, but it was getting to wordy and wasn’t all really relevant. I think hers but my husband was surprised and assumed it would be boyfriend’s last name. I’m curious to know if most think like me or if it’s still assumed babies get their dad’s last name.

Hers.

If only for practical aspects like getting a passport, travelling etc.

Depends, if the dad isn't going to be involved then hers, if she's planning to marry/take his name then it might help the dad feel included more to use his, depending if she likes that name. A lot of people hate double-barrelled names (and unless the names are going to be very long, when 2 people with such names marry, half of each will be dropped anyway), but if she likes that idea, then that would be a compromise.

Your DD needs to decide.

Why assume that she will change her name if they get married?

Stay open minded, steer clear of assumptions.

Whilst others are saying that he will still have PR for taking the child out of the country etc, it’s much easier and you are less likely to be asked if your child has the same name as you. In fact I wonder, where the father isn’t in the birth certificate, how you prove this - I suppose you always travel with passport and birth certificate?

I think that all children should be given either only their mothers name or double barrel with mothers name last so it doesn’t get dropped. I’m very surprised that in 2026 young women are still changing their names.

What nobody has mentioned is that if she gives the baby the dad's name then she would have to get his permission later on if she ever wanted to change it. If she gives it her name, if they were to marry in future (and she wanted to change) then it's much easier to change both hers and the baby's at that point.

My firstborn is now 40 and when she was born unmarried women had just started giving their baby the dad's name (where we lived), so the practice is relatively new in the grand scheme of things.

HER name, without question. We’re in 2026 now, babies don’t automatically get the father’s name.
It’s so incredibly likely that they’ll split up at some point in future if they’re only 18 and she won’t want a different surname than her child.

Because she’s already indicated she would, and she was surprised when I first mentioned my name option. Tbf, her boyfriend does have a nice surname. If all goes according to their current plans, they’ll stay together and eventually ask have the same name, whichever one they decide that to be.

@WeaselsRising that’s also a good point that I will mention if and when the topics comes up in conversation again.

Thank you to everyone who has replied. 😊

Definitely mums name.
If it works out and they do get married they can re-register the child as a child of marriage. Legitimacy laws still apply. The child gets a new birth certificate and it will show a maiden name for mum, regardless of whether she changes her name or not.
The hard facts are: the vast majority of parents split up. Unmarried parents are far more likely to split up than married parents. Young parents are even more likely to split up. This figure is not going to improve anytime soon.
So realistically if the child has dads name, it will grow up with a parent ( mum) who has a different name to them.
Add to this the very real likelihood that mum gets pregnant to someone else and that child has dads name so not only does the first child have a completely different name to their mother, they have to live with a sibling who has a different name and probably a man who has a different name. If the mum married her new boyfriend then everyone apart from the first child all have the same name. Just think how upsetting that is.
Of course there is the deed poll option, BUT father gas to agree to the name change. Plus why make your child have to constantly explain why they have changed their name?
Also, many second relationships fail too. So the poor child then as an adult changes their name AGAIN to either their real fathers name, or back to mothers maiden name!