The 020 area code primarily covers London, one of the world’s most populous and diverse cities. This sprawling metropolis is home to millions of people, businesses, and organizations, which means that the 020 area code encompasses a vast range of activities. 02045996879 who called me in uk 020 area code :   When someone calls you from this area code, it could be anyone from a long-lost friend to a potential employer or a pesky telemarketer.