Can we spell the surname differently?

[fairgame84]

We have a double barrelled surname.
DH has always joined it up but officially on passports and marriage certificate etc it's 2 words.
When baby is born can we join up the surname or will it cause us problems?

Example
Say surname is Ben Alaya but we want to spell it Benalaya.

deedpolloffice.com/change-name/law/birth-registration
Parents have can give their child whatever name or surname they want. Although it's traditional to give a child the father's surname, or, less commonly, the mother's surname, the child's surname could be a combination of both (for example) — or something completely different

Sure. Parents often don’t have the same name as their child anyway. And Anglicising a name (if that’s what you are doing) might make the child’s life easier in the end.

Thanks.
It's a real pain the arse surname because it's not hyphenated. In DHs country it's not an issue but in the UK people either miss off the Ben part or try and hyphenate it. Whenever I pick up my prescriptions it's either in the B or A box, people get confused. It sounds exactly the same when it's all one word.

Could you do it as people do with Mac or Mc surnames?

Run the two names together but keep the capital letter of the second part, like McDonald, MacGowan, etc.. No hyphen, no space.

I think it's a huge pity to essentially lose the meaning of the two part name by using the lower case letter in the second part. Cultural loss is always a big loss imo.

That's a good idea @mathanxiety thanks