Capital gain tax on GBP corporate bond

The GBP corporate bond was issued at £100 with a coupon of 4% for 5 year maturity. The bond subsequently traded down and I purchased it from secondary market at £80 with remaining 3 years to maturity. Do I need to pay capital gain tax on the £20 capital gain? Would there be any difference if the issuer is a UK company or non-UK company? Would it be considered as Deep Discounted Securities as I purchased it way below its issued price?

Hi,

You can see guidance here:

CG53702 - Qualifying corporate bonds: general definition

If a security is not a qualifying corporate bond, then it is treated in the same way as any other asset to which the Taxation of Chargeable Gains Act would apply.

Thank you.