According to the Ministry of Information and Communication, most of the digital repository is used for fixed-line phones, and only a few for mobile phones – whose subscribers account for 95 percent of total telephone subscribers in Vietnam.
The separation and merging of cities and provinces made fixed-line area codes inconsistently long.
The ministry has promulgated Circular No.22, which took effect from March 1, 2015, on digital repository planning, including the change of landline phone area codes in 59 out of 63 localities across the country.
The plan is divided into three phases, with the first phase starting from February 11, 2017, for 13 cities and provinces, namely Son La, Lai Chau, Lao Cai, Dien Bien, Yen Bai, Quang Binh, Quang Tri, Thua Thien – Hue, Quang Nam, Da Nang, Thanh Hoa, Nghe An, and Ha Tinh.
The second phase will start from April 15 this year for 23 cities and provinces, and the last one will start from June 17 for the remaining, including Hanoi and Ho Chi Minh City.
The area codes for northern Vinh Phuc, Phu Tho, Hoa Binh and Ha Giang provinces will not be changed.
The MoIC said its aim is to make all area codes uniformly three digits; currently there are one-, two- and three-digit codes. With the new codes, all phones numbers will have 11 numbers; they range from 10 to 11 now.
The ministry will use the opportunity to renumber phone codes based on geographical location.
Provinces in the north-western region, for example, will have their codes begin with 21.
The north-eastern region above Hanoi will have the new code of 20x, while the sub-Hanoi region’s will be 22x.
The dialling codes of the upper half of the central region will begin with 23, while it will be 25 for the lower half.
The new code for provinces in the central highlands will be 26x, in the south-eastern region it will be 27x, while in the south-western region it will be 29x.
Hanoi and HCM City will be the only two cities to have two-digit codes of 24 and 28, respectively.
The codes of the three central cities of Can Tho, Da Nang and Hai Phong will be 292, 236 and 225, respectively.
The changes will be completed on August 31, 2017.