I prefer to be called by my maiden name by colleagues and friends. Is it unprofessional or illegal to use my maiden name at school and even after graduation?
I know a variety of women who have retained their maiden names for publications (some because they started publishing before getting married and changing their legal name). If they had been publishing before getting married, one concern is making it easy to link all their publications under one author name, making it easier to see their whole record. (But, even that is not required, having seen publication lists where it rapidly becomes clear that there was a name change - I hope things like Web of Science figure it out, but I'm not sure.)
I also know a number that never changed their name legally to begin with. That is not uncommon, at least in the US.
Likely you know such people as well, or looking around your university would find some fairly quickly.
So, bottom line, do what you and your partner are comfortable with, the academic world has seen it before and is just fine with it.
In the UK, you can legally use just about any name you choose, and change your name (or not change your name) as and when you see fit. In fact, a married woman is under no obligation to use her spouse's surname at all (not even on her passport), although many still do so socially and for identity documents (because border-control officials ask more questions if a parent and child have different surnames in their passports -- a copy of the child's birth certificate is normally adequate proof of parentage).
In academia (and many other professions), it is very common and positively recommended for married women to use maiden names professionally (irrespective of which name is used socially and on identity documents). This is because changing name makes it harder to maintain any recognition or reputation acquired under the old name.
Having said that, I know various academics who have changed name in interesting ways. Among my colleagues, there is:
a male academic who changed his surname for professional/public purposes, but keeps his 'original' surname on his passport and tax records (the reason he made the change was that, with the 'original' surname, he could have been confused with someone else in the same field);
a male academic who uses a surname consisting of his wife's maiden name followed by his own 'original' surname (as a result, you can surmise when he married from when that extra name started appearing on his publications);
a female academic who uses a surname consisting of her ex-husband's surname followed by her maiden name (and she has remarried!).