Area Code 4007 – Taichung/Changhua

Overview of Area Code +886 4007

Area code 4007 is a geographic routing code within the Taiwan national numbering plan, administered by the National Communications Commission (NCC) under the ITU-T E.164 international standard. This code is allocated to the central-western region of Taiwan, specifically the Taichung and Changhua metropolitan areas. It is important to note that 4007 is not a subscriber number but a National Destination Code (NDC) that routes calls to fixed-line (PSTN) subscribers within the designated geographic area.

Geographic Coverage and Administrative Jurisdiction

The 4007 code serves the city of Taichung (台中市) and the surrounding Changhua County (彰化縣). Taichung is a special municipality and the second-largest city in Taiwan, with a population exceeding 2.8 million. Changhua County, located to the south of Taichung, is a major agricultural and industrial hub. The code covers both urban districts (such as Xitun, Nantun, Beitun, and Central Taichung) and suburban/rural areas within the two administrative divisions.

Dialing Formats and Caller Instructions

For domestic callers within Taiwan, the local dialing format is 04-4007-XXXX (where XXXX is the subscriber number). The leading '0' is the trunk prefix used for domestic long-distance calls. When calling from outside Taiwan, the international format is +886 4 4007 XXXX (or +886 4 4007XXXX). The country code for Taiwan is +886, and the '0' is dropped. For example, a local call from Taipei to a number in Taichung would be dialed as 04-4007-1234, while an international caller from the United States would dial 011-886-4-4007-1234.

Overlay and Numbering Considerations

Taiwan has implemented several overlay codes to meet the growing demand for fixed-line numbers. The 4007 code is part of the 04 numbering area, which originally covered the entire Taichung/Changhua region. Overlays such as 4007 may be used for new subscriber lines, especially in areas where the original 04-XXXXXXX numbers are exhausted. This means that a single geographic area may have multiple NDCs, and callers must dial the full 10-digit number (including the area code) even for local calls in some cases. However, within the 04 area, local calls typically require only the 8-digit subscriber number (e.g., 4007-XXXX) if the caller is in the same charging group.

Technical and Regulatory Notes

Numbers under 4007 are assigned to fixed-line operators such as Chunghwa Telecom, as well as alternative fixed-line carriers. They are primarily used for residential and business lines, including VoIP-based fixed services that are geographically tied to the Taichung/Changhua region. Number portability is available in Taiwan, allowing subscribers to retain their 4007 numbers when switching operators, but the geographic significance remains. For emergency services, callers in the 4007 area should dial 110 (police) or 119 (fire/ambulance) without the area code.