02 1: Shanghai
022: Tianjin
023: Chongqing
024: Shenyang City, Liaoning Province (Northeast Regional Central Bureau; Northeast uses 4 prefixes and 3 area codes), Tieling City, Fushun City and Benxi City.
025: Nanjing City, Jiangsu Province (East China Regional Central Bureau; 3-digit area code with 5 prefixes in East China)
026: Not specified, reserved
027: Wuhan City, Hubei Province (Central South Regional Central Bureau; 3-digit area code with 7-digit prefix in Central and South China)
028: Chengdu, Sichuan Province (Southwest Central Bureau; Southwest area code with 8 prefixes and 3 digits), Ziyang, Meishan.
Extended data
Numbering principle:
The first level is the capital Beijing, where the National Convergence Center and major international interface bureaus are located. The one-digit area code is 1 (later changed to 10).
The second level uses two-digit area codes for municipalities and regional centers. At that time, the three municipalities directly under the Central Government, except Beijing, used 1 (later changed to 10), and Shanghai and Tianjin used 2 1 and 22 area codes respectively. The central cities in Northeast China, East China, South China, Central China, Southwest China and Northwest China, Shenyang, Nanjing, Guangzhou, Wuhan, Chengdu and Xi 'an use area codes 24, 25, 20, 27, 28 and 29.
26 is the area code reserved for the regional exchange center in Taiwan Province Province, which can also be understood as reserved for Taibei. Because Taiwan Province Province ranks in East China in the administrative division sequence, the area code of Nanjing, the regional exchange center in East China, is the last one.
The third level is the provincial exchange center and the regional exchange center, using three-digit area code, with the first digit corresponding to the last digit of the two-digit area code of the city where the regional exchange center is located (except North China and South China), and the second digit of the area code is five odd numbers of 1, 3, 5, 7 and 9. Provincial exchange centers (usually the capitals of provincial capitals and autonomous regions) have a mantissa of 1, except for provinces that also have regional exchange centers. In this way, the three-digit area code prefixed with 6 is also reserved for Taiwan Province Province because 26 is reserved.
The fourth level is the county exchange center, which uses a four-digit area code. The first digit is the same as the first digit of the three-digit area code of the trading center in the corresponding region, and the second digit uses five even numbers of 2, 4, 6, 8 and 0.