Area Code 1236 – Chitose, Hokkaido

Overview of Area Code 1236

Area code 1236 is a geographic National Destination Code (NDC) assigned to Chitose, Hokkaido, Japan. Chitose is a city located in the Ishikari Subprefecture of Hokkaido, the northernmost island of Japan. The city is known for its industrial base, including electronics and aerospace, and hosts the New Chitose Airport (CTS), a major international gateway. The area code covers the city of Chitose and its surrounding administrative districts, including the former town of Eniwa (now a separate city but still within the same numbering area).

Dialing Formats

When calling a landline in Chitose from within Japan, you must dial the trunk prefix 0, followed by the area code 1236, and then the subscriber number (which is typically 6 digits). The full national format is: 0-1236-XX-XXXX. For example, a local number might be 0123-45-6789.

When calling from outside Japan, you must dial the international access code (e.g., 011 from the US, 00 from many countries), followed by Japan's country code +81, then the area code without the leading zero, and the subscriber number. The international format is: +81-1236-XX-XXXX. For instance, if the local number is 0123-45-6789, you would dial +81 1236 45 6789 from abroad.

Geographic Coverage and Jurisdiction

The 1236 area code is administered by the Ministry of Internal Affairs and Communications (MIC) and is allocated to the Chitose numbering area, which includes the city of Chitose and the city of Eniwa. Both cities are part of the Ishikari Subprefecture. The area is served by NTT East (Nippon Telegraph and Telephone East Corporation) for fixed-line services, though alternative carriers may also operate.

Caller Instructions

• Local callers (within Chitose/Eniwa): If you are calling from a landline within the same area code, you may be able to dial just the 6-digit subscriber number (without the area code) in some cases, but it is safer to always dial the full number including the area code to avoid misdialing.
• Callers from other parts of Japan: Dial 0-1236-XX-XXXX (replace X with the subscriber number).
• Callers from overseas: Dial your international exit code, then 81, then 1236 (drop the leading 0), then the subscriber number. Example: +81 1236 45 6789.

Overlay and Numbering Considerations

As of the latest information, there is no overlay code for the Chitose area; 1236 remains the sole area code for this region. However, due to the growth of VoIP and mobile services, number portability allows users to retain their numbers when switching service providers, but the geographic significance of the code remains for fixed-line identification.

For businesses or individuals in Chitose, it is important to note that the area code is part of the Japanese numbering plan and is subject to regulations by the MIC. The subscriber number length is fixed at 6 digits, making the total national significant number (NSN) 10 digits (including the leading 0).