Area code 021

021 is:


 * in Brazil, the telephone area code for the city of Rio de Janeiro and surrounding cities (Greater Rio de Janeiro)
 * in China, the telephone area code for the city of Shanghai.
 * in Indonesia, the area code for the city of Jakarta and surrounding cities.
 * in Iran, the telephone area code for the capital city of Tehran.
 * in Ireland, the area code for the city of Cork and a surrounding part of County Cork.
 * in Libya, the telephone area code for the capital city of Tripoli.
 * in Nepal, the Nepal Telecom telephone area code for the district of Morang.
 * in New Zealand, the "area code" for cellular phones on the Vodafone network.
 * in Pakistan, the telephone area code for the city of Karachi.
 * in Serbia, the area code for the city of Novi Sad.
 * see Telephone numbers in South Africa.
 * in Sweden, the area code for the city of Västerås; see Telephone numbers in Sweden.
 * in the United Kingdom, the former area code for Birmingham England (changed to 0121 on 16 April 1995).