Taxes on exercised share options

Hi All, My former employer granted me share options, providing a fixed price to buy the shares once the options became vested and there was an available window to purchase them. I have since exercised those options. The fixed price to buy the shares is very low, lower than the estimated market value (according to an estimation made by an external company). Currently, there is no market available to exchange these shares. This means that if I purchase the shares, I cannot sell them, and it's uncertain whether I will ever be able to do so. After reviewing the guidance provided in the following resources: https://www.gov.uk/tax-employee-share-schemes/company-share-option-plan https://www.gov.uk/check-if-you-need-tax-return It seems that I shouldn't be liable to pay any tax at the moment. The tax would only be applicable in the event of future sales as a Capital Gain. So, my question is: is it needed to declare the difference between the estimated market value and the cost of purchasing the shares? If yes, could you please indicate which section of the Self-assessment should be used? Additionally, as I'd need to claim tax relief for expenses for working from home, could you please advise on which section of the self-assessment I should utilise?

Hi andy20,
There is nothing that you would need to do, until you dispose of them.
Only then would you be looking at the acquistion costs, to work out if there is any capital gain.
Even then you would only have to report the gain, if you have capital gains tax to pay.
You can report and pay your capital gains here:
Report and pay your Capital Gains Tax
Or in a Self Assesment tax return.
Thank you.