Area Code 370 – Karabuk

Overview of Area Code 370 (Karabük, Türkiye)

Area code 370 is a geographic National Destination Code (NDC) assigned to the province of Karabük in the Western Black Sea region of Türkiye. It covers the provincial capital Karabük and its districts, including Safranbolu, a UNESCO World Heritage Site renowned for its Ottoman-era architecture, as well as Eskipazar, Eflani, Ovacık, and Yenice. The code is used for fixed-line (PSTN) services within this administrative area.

Dialing Formats

When calling a Karabük landline from within Türkiye, you must dial the trunk prefix 0 followed by the area code and the subscriber number. The national significant number (NSN) for geographic numbers in Türkiye is 10 digits, comprising the area code (3 digits) and a 7-digit subscriber number. For example, a typical local number might be 370 123 45 67.

• National call (from another province): 0 370 123 45 67
• International call (from abroad): +90 370 123 45 67

If you are calling from a mobile phone within Türkiye, you can use the same national format (0 370 ...). However, note that some mobile operators may require the full national number without the initial 0 when roaming internationally.

Overlay and Numbering Plan

As of the latest ITU-T E.164 national numbering plan updates, there is no overlay code for Karabük. The 370 code is exclusively assigned to this province. Subscriber numbers are 7 digits long, and the total length of a national significant number (including the area code) is 10 digits. This structure complies with Türkiye's national numbering plan, managed by the Information and Communication Technologies Authority (BTK).

Caller Instructions

For callers within Türkiye: Always include the trunk prefix '0' when dialing from a fixed or mobile line outside the local area. If you are within the same area code, you may be able to dial only the 7-digit subscriber number, but this depends on your operator's local dialing rules.

For international callers: Replace the trunk prefix with the country code for Türkiye (+90). Drop the leading '0' of the area code. Thus, the international format is: +90 370 123 45 67.

Important Notes

Geographic numbers in Türkiye are primarily used for fixed-line services, but they may also be assigned to VoIP services that provide fixed-line equivalents. When dialing from abroad, ensure you have the correct international access code (e.g., 00 from most European countries, 011 from the US/Canada). Always verify the subscriber number length, as some numbers may have fewer digits if they are older or if the numbering plan has been adjusted.