Area Code 259 – Sado, Niigata
The phone area code for Sado, Niigata is 259 (international format +81259). Browse local exchange codes (NXX) and carrier assignments below.
📍 Geographic Location of Sado, Niigata
Overview of Area Code 259
Area code 259 is a geographic numbering plan area (NPA) in Japan, assigned to Sado Island, part of Niigata Prefecture. It covers the entire island, including the city of Sado and its administrative districts. The code is used for fixed-line (PSTN) services, and calls to this region require the national trunk prefix 0 when dialed domestically.
Geographic Coverage and Administrative Jurisdiction
Sado Island is located in the Sea of Japan, off the coast of Niigata Prefecture. The area code 259 serves the city of Sado, which was formed in 2004 by the merger of several towns and villages. Key localities include Ryotsu, Aikawa, and Ogi. The island is known for its cultural heritage, including the Sado Kinzan gold mine and the annual Earth Celebration music festival.
Dialing Formats
For local calls within the Sado area, callers can dial the 6-digit subscriber number directly, omitting the area code. For domestic long-distance calls from other regions in Japan, the format is: 0-259-XX-XXXX, where the leading 0 is the trunk prefix. For international calls to Sado from abroad, callers should dial +81-259-XX-XXXX, dropping the leading 0. For example, a local number such as 12-3456 would be dialed as 0259-12-3456 domestically and +81 259 12 3456 internationally.
Overlay and Numbering Considerations
Currently, there is no overlay code for area 259; it is the sole area code for Sado Island. The subscriber numbers are 6 digits long, making the total national significant number (NSN) 10 digits when including the area code (excluding the trunk prefix). The numbering plan follows ITU-T E.164 recommendations, and the country calling code for Japan is +81.
Caller Instructions
For local callers within Sado, simply dial the 6-digit number. For callers from other parts of Japan, dial 0259 followed by the subscriber number. For international callers, use the international access prefix (e.g., 011 from the US) then 81, then 259, and the subscriber number. Ensure to drop the leading 0 of the area code when dialing internationally.