The area code of China is stipulated by the state, and each city has a different area code. Tianjin is a municipality directly under the central government of China and an important economic center and port city in northern China. According to national regulations, the area code of Tianjin is 022, which is used to dial the telephone number of Tianjin. To call a landline in Tianjin, you need to dial the area code 022 first and then the corresponding telephone number.