GOV UK Income Tax calculator personal allowance

Hi, Does the calculator https://www.tax.service.gov.uk/estimate-paye-take-home-pay/ correctly calculate reduced personal allowances? I get conflicting figures when filling in my self-assessment (1 job on paye, no other income) compared to the calculator on the link above Thanks

Hi,

The calculator should automatically calculate reduced personal allowances, depending on the information provided. If you don't think the estimate is accurate or you'd like advice on how to complete your Self Assessment return.

You can contact our Self Assessment team at:

Self Assessment: general enquiries

Thank you.