Inside IR35 Contractor - Unclear if I need to complete a self assessment tax return

Good afternoon, I am getting in touch as I am a first time contractor (inside IR35 operating through an umbrella company) and I am not entirely sure whether I should complete a self-assessment tax return or not. My taxable pay for the year is slightly above £100k but below £150k. I understand that the threshold has now gone up to £150k, but I am not clear whether this applies to my circumstances. I have also contributed around £3,000 to a NEST pension (through employer contributions). Subtracting this amount from my taxable pay would take it below the £100k threshold, however I am not entirely sure whether this is indeed something I can subtract as it is not clear to me whether this is taxed or not. Any advice would or clarification would be greatly appreciated. Best

Hi,

You can check if you need to file a return here:

Who must send a tax return

Thank you.