US capital gains tax

How are capital gains from sale of US stocks taxed for a UK resident?

Context: I bought and sold shares of Slack pre and post the acquisition announcement (held it for 2 weeks only; short term) - netting a handy profit. I have since cashed out and would like to understand if I am supposed to declare this income? How will it be taxed?

It’s the same as UK stocks. You don’t pay capital gains tax in the US but you do in your own country.

You don’t need to declare anything if your total capital gains for the financial year are below the Capital Gains tax-free allowance, which is currently £12,300.
If you do need to report your gains, you should report the GBP value


Appreciate it - thank you.