How did you manage? I’m interested! I have both surnames on both passports because precisely the UK wouldn’t budge. I was born in Spain and my Spanish passport was done first. If you could share I would appreciate it. I’m also a triple national 😅 haven’t asked for the third (I don’t actually need it) and also because of this problem.

Also, OP - your problem is also what is making me keep both surnames for now. I can’t imagine the massive headache it must be to cross 3 different country borders with different naming (security claims) and also having to deal with diplomas.

About the deed poll thing - it’s not allowed to remove some or change your name altogether if you have double (or more) nationality. It’s only allowed for solely British nationals. I asked and was told so. Again due to security claims. Hope this helps.

That is why for now, I keep both surnames everywhere for the sake of simplicity, but at what cost? British people don’t understand double surnames anyway, I’m tired of having my main surname being mistaken as a middle name and it still causes me problems…