What countries in Europe use their own currencies?

As of October 2023, several European countries use their own currencies instead of adopting the euro. These include the United Kingdom (British pound), Switzerland (Swiss franc), Norway (Norwegian krone), Sweden (Swedish krona), and Denmark (Danish krone). Additionally, countries like Hungary (Hungarian forint) and Poland (Polish złoty) also maintain their national currencies. These nations have opted to retain their currencies for various economic and political reasons.