The new rules as of October 4th 2021 mean that your tests for travel will be more dependent on your vaccination status than your destination.
The new list is now: Rest of the World and Red List.
If you are returning from a rest of the world country be sure to check the exact travel requirements of the country via the GOV website. If you qualify as fully vaccinated you will just need a day 2 test.
If you are not fully vaccinated you will need a day 2 and 8 test.
If you are returning from a Red country, you must book your government quarantine hotel, a Day 2, and a Day 8 test.
To check what list the country you’re travelling to is on visit the gov.uk website.