Should I be paying tax?

[idontfitintoabox]

I'm so confused, if someone could help then I'd be most grateful!

I earn £16096 pre tax a year (full time) but I've only been paying NI, however this month I got charged about £50 for Income Tax additionally which I've never had to pay before- is this right?

Probably. Tax free allowance is £12500 pa so unless you are laying some pension contributions that sounds correct

How much did you earn last year - tax year ends on 5 April so your year's total will probably be on your March payslip.

Depending on how much your pension contribution is, you should be paying 20% on everything above the tax threshold, say you earned the same last year, paid £1000 into your pension, you'd pay about £600 tax a year, plus NI on top, so the £50 a month income tax is spot on.

Did you earn less last year? What does it say on your 2019/20 pay slips?

Yes. It may be that you previously had more of your allowance so didn't need to pay tax.
That would be right sort of amount for an annual salary of that level.

Did you start your job, get a pay rise or move from part time to full time some time after 6 April 2019, so even though your salary was the £16096, you didn't earn it for all the year, so didn't exceed the tax threshold.