Free childcare: Please help in calculating what my adjustable net income is

Hi I am confused about free childcare and adjustable net income. Per my P60 for 2023-24, my taxable income was £110,380 (after deducting the payments into workplace pension). During the year I also paid into private pension in the amount of £7,760. My private pension contribution was grossed up by basic rate of 20% to £9,700. I know I can claim another 20% (£1,940) when filing self assessment. Please advise which of the following calculations for adjustable net income are correct: a) £110,380 - £9,700 = £100,680 b) £110,380 - £9,700 - £1940 = £98,740 If (b) is correct, what document would I need to submit in order to prove the adjustable net income for 15 hour free childcare Many thanks in advance.

Hi,

The correct calculation will be a). 

Thank you.