First time self assessment - Pension confusion

As the title suggests this the first I have completed a self assessment form and the way the pension contributions are handled is confusing me. I am completing the form because I may have to pay a Child Benefit charge and so I am looking to reduce my Adjusted Net Income. I pay personal pension contributions into the workplace pension scheme over and above the work contributions. The personal contributions are paid before tax is deducted. I recognise that the tax relief isnt due because of this, but I wonder where I enter the total contribution value in the self assessment form? I was looking to see if the contributions can be deducted from the Taxable income on the P60 to give Adjusted Net Income but I don’t think it can. Am I right in saying that the gross contributions are entered at "Payments to registered pension schemes (Also known as PPR) where basic rate tax relief will be claimed by your pension provider (called Relief at source). Enter the payments and basic rate tax:" If it isnt - can someone advise where I get the benefit on the contributions?

Hi,

If the personal contributions are paid before tax is deducted, no further tax relief is due - as such, you would not need to declare these contributions on your tax return.

Thank you.