What reasons are there for a nil tax code?

maxmycardagain

its no-ones business but yours, tax codes and wages are personal, tell the nosey git "ask no questions, you get no lies"

Praxis99

There are other reasons why an NT code might be applied such as students at university or college who only work during their holidays (I remember doing this while a student to stop my TA pay been taxed, it was very helpful at the time), and some UK employees who work abroad.

However I think by far and away the most common reason will be BR. That said in a large organisation where to payroll you are just pretty much a name and number this is highly unlikely to cause you any potential embarrassment, but in a smaller organisation where payroll is handled by a person you know personally it might since it won't take much for them to put 2 and 2 together.

So you will know that they 'probably know' in the type of scenario described above but if they are 'professional' in there duties they won't say anything or be discrete if they need to query something with you, since what does it matter to them anyway?