How to fill in the self assessment form on second PAYE payment

I have a fulltime PAYE job. In 2023-24 I did some freelance work for a second company. They also paid me through their PAYE payroll, where I was taxed. I want to do a self assessment form as I incurred some expenses during the freelance work which I want to claim back. On the self assessment form it asks me for the Turnover of the freelance work. Do I put the pre-tax amount the second company paid me, or the post-tax amount I actually received? How do I indicate that I have already been taxed on this payment and should not be taxed again? Additionally, in my fulltime job I received health insurance as a benefit. The self-assessment form asks how much this was, but my payslip only lists a nominal amount for tax each month and my P60 doesn't have a final figure for the year. Do I need to go through each payslip and add up these nominal amounts?

Not HMRC...as the 2nd company has paid you under PAYE this is also employment, you cant show this separately as self employed/freelance income, so you will have two sets of employment pages, one for each. If there are allowable expenses these are also claimed against the second employment on the employment page. You would only show the health benefit on the SA form if you have a P11d, meaning it hasnt gone through payroll, if its gone through payroll its already been taxed and doesnt need to be shown separately.

Hi hzh,
If the freelance was paid through PAYE then this would be declared as an employment and not self employed.
If you have answered yes to the self employed question then you would need to delete the self employed section and then declare as employent.
If you received medical benefit and was not taxed through your payroll then the employer will send you a form P11d with the taxable benefit amount to declare.
If already taxed through your salary then you would not have to declare separately.
If the expenses are below £2500 then you do not ot complete a Self Assessment you can complete a P87 instead:
Claim tax relief for your job expenses if you cannot claim online
Thank you.