Area Code 321 – Mojokerto/Jombang

Overview of Area Code +62 321

Area code 321 is a geographic National Destination Code (NDC) within the Indonesian public switched telephone network (PSTN), assigned under the country's country calling code +62. It serves the regencies of Mojokerto and Jombang in East Java Province. The numbering area encompasses the administrative territories of Mojokerto Regency (excluding the city of Mojokerto, which uses a separate code) and Jombang Regency, including their respective capitals and surrounding districts.

Geographic Coverage and Administrative Jurisdiction

The 321 area code covers a predominantly agricultural and industrial region, with key urban centers such as Mojosari, Puri, Sooko, and Trowulan in Mojokerto, and Jombang, Diwek, and Peterongan in Jombang. The area is strategically located between the major cities of Surabaya (area code 31) and Kediri (area code 354), and is traversed by major transportation corridors.

Dialing Formats and Caller Instructions

For local callers within the 321 area code, the trunk prefix 0 is not required; they can dial the 7-digit subscriber number directly. For example, to call a fixed line in Mojokerto from within the same area, one would dial 321XXXXXXX (where X represents the local subscriber number). However, the standard format for domestic long-distance calls from other Indonesian regions is to dial 0-321-XXXXXXX. For example, a caller in Jakarta would dial 0321-XXXXXXX.

International callers must use the full international format: +62 321 XXXXXXX (or 0062 321 XXXXXXX when using the international exit code from certain countries). The leading '0' of the trunk prefix is omitted when dialing from abroad.

Numbering Structure and Overlays

Subscriber numbers in the 321 area code are 7 digits long, making the total length of a domestic number (including the NDC) 10 digits, excluding the trunk prefix. No overlay codes are currently active in this area; the 321 code remains the sole geographic code for the region. However, as with all Indonesian fixed-line services, numbers are portable within the same operator but not across different geographic areas.

Practical Considerations for Callers

When calling from a mobile phone, the same dialing rules apply: use 0321 for domestic calls and +62 321 for international calls. It is important to note that calls to fixed lines in this area are typically charged at domestic rates, which may vary depending on the caller's operator and subscription plan. For businesses or individuals frequently contacting clients in Mojokerto or Jombang, saving the number in international format (+62 321 XXXXXXX) is recommended to avoid confusion when traveling abroad.