Area Code 2679 – Saku, Nagano

Overview of Area Code 2679

Area code 2679 is a geographic National Destination Code (NDC) within the Japanese numbering plan, assigned to the city of Saku and its surrounding areas in Nagano Prefecture. This code is part of the larger Saku telephony exchange area, which historically used the 0267 area code. The introduction of 2679 as an additional NDC serves as an overlay for the same geographic region, allowing for the expansion of telephone numbers without changing existing subscriber numbers. This overlay does not require local calls to include the area code when dialing within the same NDC, but it does mandate 10-digit dialing for calls between different NDCs in Japan.

Geographic Coverage and Administrative Jurisdiction

The 2679 area code serves Saku City and the neighboring municipalities, including parts of the former Minamisaku District. Saku is located in the eastern part of Nagano Prefecture, approximately 150 kilometers northwest of Tokyo. The region is known for its agricultural production, historical sites, and as a bedroom community for commuters to the Greater Tokyo area. The administrative jurisdiction falls under the Nagano Prefectural government, with local telecommunications services provided by NTT East and various competitive local exchange carriers.

Dialing Formats and Caller Instructions

For local callers within the Saku area (i.e., when both caller and recipient share the 2679 area code), it is possible to dial the 7-digit local subscriber number without the area code. However, due to the overlay, it is recommended to always dial the full 10-digit number (area code + subscriber number) to avoid confusion and ensure proper routing, especially in areas where both 0267 and 2679 are in use. For callers from other parts of Japan, the international format is not used; instead, dial the national trunk prefix 0, followed by the area code 2679 and the 7-digit subscriber number. For example, to call a number in Saku from Tokyo, dial: 0-2679-XXXXXX (where XXXXXX represents the 6-digit subscriber number, as Japanese geographic numbers are typically 10 digits total including the area code).

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 +81-2679-XXXXXX. It is important to note that the subscriber number length is 6 digits, making the complete national significant number 9 digits (2679 + 6 digits), which aligns with ITU-T E.164 recommendations for Japan.

Overlay Considerations and Number Portability

The overlay of 2679 with the existing 0267 area code means that new telephone numbers in Saku may be assigned with either area code. This does not affect the geographic location of the number; both codes are tied to the same rate center. Subscribers can retain their numbers when switching between carriers, thanks to number portability regulations in Japan. However, it is essential for businesses to update their contact information to reflect the correct area code, as dialing patterns differ. When calling from abroad, it is crucial to use the correct country code and area code without the leading zero to ensure successful connection.