The EU countries are:
Austria, Belgium, Bulgaria, Croatia, Republic of Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden.The European Economic Area (EEA)
The EEA includes EU countries and also Iceland, Liechtenstein and Norway. It allows them to be part of the EU’s single market.
Switzerland is neither an EU nor EEA member but is part of the single market - this means Swiss nationals have the same rights to live and work in the UK as other EEA nationals.
Any other country is non-EU
More details can be found here:
Continuing to work in the UK if you're an EU, EEA or Swiss citizen:
You and your family usually need to apply to continue living in the UK after 31 December 2020 if you’re from any of the following:
- the EU (except Ireland)
The Common Travel Area (CTA) is a long-standing arrangement between the UK, the Crown Dependencies (Bailiwick of Jersey, Bailiwick of Guernsey and the Isle of Man) and Ireland that pre-dates both British and Irish membership of the EU and is not dependent on it.
Under the CTA, British and Irish citizens can move freely and reside in either jurisdiction and enjoy associated rights and privileges, including the right to work, study and vote in certain elections, as well as to access social welfare benefits and health services.
Therefore although Ireland is still a member of the EU if you are an Irish citizen with a valid Irish passport and a UK national insurance number you don't need to demonstrate your right to work in the UK with any additional documents.
For more details on the differences for right to work between UK, EU and Non-EU Citizens click here: