Area Code 4280 – Tachikawa, Tokyo

Overview of Area Code 4280

Area code 4280 is a geographic prefix assigned to the Tachikawa area, located in the western part of Tokyo Metropolis, Japan. In the Japanese numbering plan, this code falls under the broader 042 region, which serves multiple cities in the Tama area. Specifically, 4280 is a central office code within the Tachikawa exchange, used for landline telephone numbers. The full national significant number for a subscriber in this area is 042-80X-XXXX, where X represents additional digits. Internationally, callers must dial +81 42 80X XXXX, omitting the leading zero.

Geographic Coverage and Administrative Jurisdiction

Tachikawa is a city situated in the northern part of the Tama region, approximately 40 kilometers west of central Tokyo. It functions as a major commercial and administrative hub for the area, hosting the Tachikawa City Hall and several government offices. The 4280 prefix is allocated to fixed-line services within Tachikawa and may also cover adjacent neighborhoods that are part of the same telephone exchange area. The city is well-connected via the Chuo Line and Tama Toshi Monorail, making it a key residential and business district.

Dialing Formats and Caller Instructions

• Local calls (within Japan): Dial 042-80X-XXXX. The leading 0 is part of the national trunk prefix.
• International calls (from abroad): Dial your country's exit code, then 81 (Japan's country code), then 42 80X XXXX. Do not dial the leading 0.
• Calls from other regions in Japan: Dial 042-80X-XXXX, even if calling from a different area code. No additional prefix is required.

Overlay and Numbering Considerations

The 042 area code is not an overlay; it is a standalone geographic code. However, within the 042 region, multiple central office codes (such as 4280) are used to serve different cities and wards. As of recent years, there are no overlay plans for the 042 area, meaning that local numbers remain 8 digits long (excluding the area code). Subscribers in Tachikawa have access to standard PSTN services, ISDN, and increasingly VoIP-based fixed lines, but the geographic nature of the number remains unchanged.

Practical Examples

For instance, a business in Tachikawa might have the number 042-801-2345. To reach this number from the United States, a caller would dial 011-81-42-801-2345. From a mobile phone in Japan, the same number is dialed as 042-801-2345. Understanding these formats ensures seamless connectivity for both domestic and international callers.