Area Code 4704 – Tateyama, Chiba

Overview of Area Code 4704

Area code 4704 is a geographic numbering plan area (NPA) within the Japanese telephone numbering plan, specifically allocated to the city of Tateyama in Chiba Prefecture. This code is part of the broader 470 area code region, which serves the Bōsō Peninsula's southern coastal areas. The 4704 prefix is assigned to fixed-line PSTN (Public Switched Telephone Network) services, including traditional analog lines, ISDN, and some VoIP-based fixed services that are required to display geographic numbers.

Geographic Coverage and Administrative Jurisdiction

The 4704 area code covers the city of Tateyama and its surrounding administrative districts, including parts of the former town of Tomiura and the Minamibōsō area. Tateyama is located at the southern tip of the Bōsō Peninsula, facing Tokyo Bay to the west and the Pacific Ocean to the east. The city is known for its coastal scenery, marine industries, and the Tateyama Port. The numbering area is administered by the Ministry of Internal Affairs and Communications (MIC) of Japan, with operational oversight by NTT East (Nippon Telegraph and Telephone East Corporation).

Dialing Formats and Caller Instructions

For local callers within the 4704 area code, the number is dialed as an 8-digit local number, typically beginning with the subscriber number (e.g., 4704-XX-XXXX). However, when calling from outside the 4704 area but still within Japan, callers must dial the trunk prefix '0' followed by the area code and the subscriber number: 0-4704-XX-XXXX. For international callers, the Japanese country code (+81) is used, and the leading '0' of the area code is dropped. Thus, an international caller would dial +81-4704-XX-XXXX. For example, a local number such as 4704-12-3456 would be dialed as 0470-412-3456 from within Japan (if outside the area) and as +81-470-412-3456 from abroad. It is important to note that the area code 4704 is not an overlay; it is a distinct code within the 470 region, and no overlay plans have been implemented for this area.

Numbering and Technical Considerations

Numbers with the 4704 prefix are 10 digits long when dialed internationally (including the country code but excluding the trunk prefix). The total number of subscriber lines is limited by the 10,000-number capacity of the 4704 exchange. As with all Japanese geographic numbers, these are used for fixed-line services and are not portable to mobile networks. However, number portability is available between fixed-line operators within the same geographic area. For VoIP services, users may be assigned a 4704 number if they have a physical presence in the area, but the service is location-independent in terms of routing. Callers should be aware that calls to 4704 numbers are charged according to the standard fixed-line tariffs of their own carrier, and from mobile phones, rates may vary.