Area Code 263 – Matsumoto, Nagano

Overview of Area Code 263 (Matsumoto, Nagano)

Area code 263 is a geographic National Destination Code (NDC) within the Japanese numbering plan, assigned to the Matsumoto metropolitan area and its surrounding municipalities in the Nagano Prefecture, located in the Chūbu region of Honshu, Japan. Under the ITU-T E.164 recommendation, the full international dialing format for a fixed-line subscriber in this region is +81 263 XXX XXX, where +81 is the country calling code for Japan, 263 is the area code, and the subsequent seven digits constitute the subscriber number. When dialing domestically from another area code within Japan, the trunk prefix 0 must be used before the area code, resulting in the format 0263 XXX XXX. This prefix is mandatory for all calls originating from outside the Matsumoto charging group, but it is omitted when dialing from within the same area code (local calls).

Geographic Coverage and Administrative Jurisdiction

The 263 area code serves the city of Matsumoto, the second-largest city in Nagano Prefecture, along with the surrounding towns and villages, including Shiojiri, Azumino, and parts of the Higashichikuma and Kamiminochi districts. Matsumoto is renowned for its historic Matsumoto Castle, a National Treasure of Japan, and serves as a regional economic and cultural hub. The area code is administered by the Ministry of Internal Affairs and Communications (MIC) and allocated to Nippon Telegraph and Telephone East (NTT East), which operates the fixed-line PSTN infrastructure in the region. As with most Japanese geographic codes, the 263 area code is not portable to mobile networks, and it remains tied to the physical location of the subscriber's line.

Dialing Formats and Caller Instructions

For international callers, the correct dialing sequence is: International Access Code (e.g., 011 from the United States, 00 from most European countries) followed by 81 (Japan's country code), then 263 (dropping the leading zero), and finally the seven-digit subscriber number. For example, to call a Matsumoto-based business with the local number 234-5678, an international caller would dial +81 263 234 5678. Domestic callers outside the 0263 area must dial 0263 234 5678. Local callers within the same code can simply dial 234-5678 without the area code. It is important to note that Japan has implemented number length standardization, and all geographic numbers are 10 digits long (including the area code) when dialed domestically with the trunk prefix.

Overlay and Numbering Considerations

As of the latest MIC updates, there is no overlay code for the 263 area; the region continues to use a single area code without the need for 10-digit dialing for local calls. However, with the ongoing migration of PSTN services to IP-based networks, some subscribers may receive numbers that are technically VoIP but retain the geographic 263 code, allowing businesses to maintain a local presence. When calling such numbers, the same dialing rules apply, but callers should be aware that VoIP numbers may have different emergency service routing characteristics. For accurate billing and routing, always verify the subscriber number length, as Japanese fixed-line numbers are strictly seven digits after the area code.