Do I have to complete a self assessment if I sell NSO stock

Hello! I am currently a UK tax resident, always paying income tax via PAYE as my salary is under the threshold. However I am planning to sell NSO stock from a previous employer via Shareworks and with the current value, I would get my salary of £90k + approximately £70k from this stock. Would this qualify as having to fill a self assessment in the respective tax year as it's over the £150k threshold or are the taxes paid at exercise and sell on the same day enough? Thank you!

Hi,
You can use this tool to find out if you need to send a tax return:
Check if you need to send a Self Assessment tax return
Thank you.
 

Hello, Thanks for your reply - I am aware this exists but my problem is that I don't know if such stocks count towards income or not.

Hi,
It would be capital gains as you are selling an asset. You can see guidance here:
Capital Gains Tax: what you pay it on, rates and allowances
Thank you.