Area Code 2618 – Omachi, Nagano
The phone area code for Omachi, Nagano is 2618 (international format +812618). Browse local exchange codes (NXX) and carrier assignments below.
📍 Geographic Location of Omachi, Nagano
Overview of Area Code 2618
Area code 2618 is a geographic National Destination Code (NDC) within the Japanese telephone numbering plan, assigned to the city of Omachi (大町市) in Nagano Prefecture. Omachi is located in the northern part of Nagano Prefecture, near the Hida Mountains (Northern Alps), and serves as a gateway to popular alpine resorts such as Hakuba and Tateyama. The code covers the administrative area of Omachi city, including its central urban districts and surrounding rural communities.
Dialing Formats
When dialing within Japan, the area code is preceded by the trunk prefix '0', resulting in the national significant number (NSN) format: 02618-XXXXX. Subscriber numbers in this area are five digits long, making the total NSN length 10 digits (excluding the trunk prefix). For international callers, the country code for Japan is +81, and the leading '0' of the area code is dropped. Therefore, the international format becomes: +81 2618-XXXXX. For example, a local number in Omachi might be 02618-2-1234, which would be dialed as +81 2618-2-1234 from abroad.
Geographic Coverage and Administration
Omachi is a city with a population of approximately 28,000 residents. The area code 2618 is administered by NTT East (Nippon Telegraph and Telephone East), which oversees the regional telecommunications infrastructure. The city is known for its scenic beauty, including Lake Kizaki and the Kurobe River, and is a hub for tourism and outdoor activities. The numbering area is exclusively geographic, meaning that the code is tied to the physical location of the fixed-line telephone service. Calls to 2618 numbers are routed via the PSTN to the Omachi telephone exchange.
Caller Instructions
For local callers within Omachi, dialing the full 10-digit number (including the area code) is required even for calls within the same city, as Japan uses closed dialing plans for geographic numbers. For callers from other parts of Japan, dial the trunk prefix '0', then the area code 2618, followed by the subscriber number. For international callers, replace the trunk prefix with the country code +81 and omit the leading '0'. No overlay codes are currently in effect for this area, so the 2618 code is unique to Omachi.
Future Considerations
As with all geographic codes in Japan, number portability is available for fixed-line services, allowing users to retain their numbers when switching carriers within the same geographic area. However, the geographic significance of the code remains, and it is not used for mobile or VoIP services unless specifically assigned to a fixed-line operator.