What city or region does area code 2550 cover in Japan?

Area code 2550 covers the Yasuzuka area, which is part of Jōetsu City in Niigata Prefecture, Japan. It includes the former town of Yasuzuka and surrounding communities.

How do I call a number in the 2550 area code from abroad?

To call a number in the 2550 area code from abroad, dial your country's international access code (e.g., 011 from the US), then Japan's country code 81, then 2550, and finally the 7-digit local subscriber number. For example, 011-81-2550-XXXXXXX.

Is area code 2550 a mobile or landline prefix?

Area code 2550 is a geographic landline prefix. It is assigned to fixed-line telephone services in the Yasuzuka area. Mobile numbers in Japan start with prefixes like 070, 080, or 090.

Do I need to dial the area code when calling locally within Yasuzuka?

No, if you are calling from within the same area code region (Yasuzuka), you can dial just the 7-digit local number without the area code. However, for calls from outside the area, you must include the area code 02550.

What is the correct format for dialing a Yasuzuka number from another Japanese city?

From another Japanese city, you should dial the trunk prefix 0, then the area code 2550, and then the 7-digit subscriber number. For example, 02550-XXXXXXX.

Area Code 2550 (Japan) - Prefix Details & Exchanges

Overview of Area Code 2550

Area code 2550 is a geographic National Destination Code (NDC) assigned to the Yasuzuka area within Niigata Prefecture, Japan. This code is part of the Japanese telephone numbering plan, managed by the Ministry of Internal Affairs and Communications (MIC) and administered by NTT East. It corresponds to the former Yasuzuka town, now merged into the city of Jōetsu. The code serves a rural, mountainous region along the coast of the Sea of Japan, known for its hot springs and ski resorts.

Geographic Coverage and Administrative Jurisdiction

The 2550 area code covers the Yasuzuka district and its immediate surroundings, including the former towns of Yasuzuka and Maki. Administratively, this area falls under the jurisdiction of Jōetsu City, which was formed by the merger of several municipalities in 2005. The region is characterized by small communities and agricultural activity, with a relatively low population density compared to urban centers.

Dialing Formats and Procedures

For local callers within the Yasuzuka area, the area code is typically omitted when dialing local numbers. The local subscriber number length is 7 digits, so a local call would be made by dialing only the 7-digit number. For callers from other parts of Japan, the full national format is used: 0-2550-XXXXXXX, where the leading '0' is the trunk prefix. For international callers, the country code for Japan is +81, and the leading '0' is dropped. Thus, an international call to Yasuzuka would be dialed as +81-2550-XXXXXXX.

Overlay Considerations

Currently, there are no overlay codes for the 2550 area. The region uses a single area code, and 10-digit dialing (including the trunk prefix) is required for all calls from outside the local area. This simplifies dialing procedures for both domestic and international callers.

Caller Instructions

For local callers within Yasuzuka: dial the 7-digit subscriber number directly. For domestic callers from other regions in Japan: dial 02550 followed by the subscriber number. For international callers: dial +81 2550 followed by the subscriber number. Always ensure you have the correct number of digits, as Japanese numbers are fixed-length.

Example

Suppose a subscriber in Yasuzuka has the number 123-4567. A local call would be made by dialing 123-4567. A call from Tokyo would require dialing 02550-123-4567. An international call from the United States would be dialed as 011-81-2550-123-4567.

Area Code 2550 – Yasuzuka, Niigata

📍 Geographic Location of Yasuzuka, Niigata