Help with a tax question please

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Is my uk tax rate (20 or 40%) calculated on my gross salary less my pension contributions ? Or is it on my gross salary, regardless of how much pension contribution I make ?

It depends - is your pension salary sacrifice?

@Crispyapple my pension is automatically taken from from my salary by my employer. I have no choice. It's taken regardless. My employer then matches the contribution

@Crispyapple just read what pension salary sacrifice is. I don't reduce my gross salary by my pension contribution.

Use this tax calculator - it will show you how it is calculated..
https://www.tax.service.gov.uk/estimate-paye-take-home-pay/your-results?csrfToken=406cfc71b196919941c9d6f1377ef2a254db47c7-1743616848561-67f40c86725a1aa627f61ffa also take a look at this.. it is very likely that your tax is calculated on your income after pension contributions.

https://www.gov.uk/tax-on-your-private-pension/pension-tax-relief.

If it your pension isn’t salary sacrifice, then your tax deduction is calculated on your gross pay, regardless of how much you contribute into your pension.
A lot of employers now offer the choice of your contributions being salary sacrifice, so may be worth checking with your payroll dept as this would reduce your taxable income, hence you would pay less tax.

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