Calculating adjusted net income

I am trying to calculate my adjusted net income for the purpose of eligibility for tax free childcare. 9.9% of salary goes into workplace pension out of my pay before deducting income tax. My question is whether my adjusted net income is my gross salary less the 9.9% contribution or is it the 9.9% contribution grossed up ie for every £1 pension contribution I make I can take £1.25 to calculate net income. The examples given don’t deal with this but the guidance says “if you made a contribution to a pension scheme where your pension provider has already given you tax relief at basic rate, take off the grossed up amount - what you paid plus the basic rate of tax”. The link in this paragraph takes you to a page where it says there are two types of pension scheme where you get relief automatically and one of these is “your employer takes workplace pension contributions out of your pay before deducting income tax”. This is the case in my situation. I don’t know if I am deducting the annual amount as it appears ie 9.9% of my annual gross salary or I am dedicating this amount x 1.2 ie grossed up.

[Dispaly name amended - Admin]

Hi stephenpaulrussell Russell,
If the pension contributions are paid before tax then no, otherwise yes.
It would be the grossed up pension contributions.
You can use the online calculator at:
Child Benefit tax calculator
If you are not sure you can contact HMRC:
Self Assessment: general enquiries
Thank you.