Area Code 2748 – Tomioka, Gunma

Overview of Area Code 2748

Area code 2748 is a geographic National Destination Code (NDC) assigned to the city of Tomioka and its surrounding areas within Gunma Prefecture, Japan. This code is part of the Japanese telephone numbering plan, which adheres to the ITU-T E.164 standard. When dialing internationally, the full country code for Japan is +81, so a typical number in this region is formatted as +81 2748 X-XXXX (where X represents the subscriber number digits).

Geographic Coverage and Administrative Jurisdiction

The 2748 area code serves the western part of Gunma Prefecture, primarily covering the city of Tomioka and neighboring municipalities such as Kanra and Shimonita. This region is known for its historical significance, including the Tomioka Silk Mill, a UNESCO World Heritage Site. The administrative jurisdiction falls under Gunma Prefecture, which is located in the Kanto region of Honshu, Japan's main island.

Dialing Formats and Caller Instructions

For local callers within the same area code (2748), it is common to dial only the subscriber number (without the area code) for calls within the same city or exchange area. However, for calls from other parts of Japan, the full national format is used: 02748 X-XXXX. This includes the trunk prefix '0' followed by the area code '2748'. For international callers, the format is +81 2748 X-XXXX, omitting the leading '0' of the trunk prefix. For example, a local number 123-4567 would be dialed as 02748 123-4567 domestically and +81 2748 123-4567 from abroad.

Overlay Considerations and Numbering Plan

As of the latest updates, there are no overlay codes for the 2748 area. The region uses a closed numbering plan for local calls, meaning that the area code is required for all calls except those within the same local exchange. The subscriber numbers in this area typically consist of 4 to 6 digits, depending on the specific exchange. The total number length for a complete international number is 11 digits (excluding the leading '+' and country code), which is standard for Japan.

Practical Information for Callers

When calling Tomioka from overseas, ensure you have the correct country code (+81) and drop the leading '0' from the area code. For example, to call a Tomioka number 2748-1234, you would dial +81 2748 1234. If you are within Japan but outside the 2748 area, dial 02748 1234. It is also important to note that Japanese numbers are often written with a hyphen after the area code, but the hyphen is not dialed. For VoIP or mobile users, the same dialing rules apply, but be aware that calls to geographic numbers from mobile phones may incur additional charges depending on your carrier plan.