what advantages are there in getting married?

[QueryA]

My friend isn't married but is wondering if she should and if there is any advantages or disadvatages that she hasn't thought of. Her situation is:

Been with partner 12 years
Have 2 kids ages 10 and 8
Both work, him FT and her 80%
They earn similar amounts
They own their home and pay equal amounts towards mortgage
He has private pension, she has NHS pension
She has slightly more savings than him
He is British, she is from EU originally but has British citizenship now

She was asking me if I think she should get married, she is not bothered about a big wedding. I couldn't really tell her any advantage to be honest.

Pessimistically, every relationship ends, whether by separation or death, and I think in the majority of cases having been married makes things easier.

As they are similar earners/assets I don’t think financially there’s much advantage if they divorce.

However if one partner dies they need to have done all the paperwork that means everything is left to the other, and make sure they’re below IHT threshold as they will pay tax if not married.

Also nok decisions for medical treatment- unless married it will be their next of kin, parents, children if old enough, rather than each other.

They have very similar incomes at the moment. No idea if that will change in future.

Hadn't thought about the next of kin thing though, that is possibly an advantage

She would likely have a lot to lose in pension should they separate unless the other half has saved very hard indeed into their private scheme.

Otherwise as above.

I got married as my self employed DH saves thousands in tax if he is married.

I got married as my self employed DH saves thousands in tax if he is married

How? Do you earn significantly less or something?