Area Code 11 – Mobile Network

Overview of South Korea's +82 11 Mobile Prefix

The +82 11 country and prefix combination is a cornerstone of South Korea's mobile telecommunications landscape. Assigned under the National Numbering Plan administered by the Ministry of Science and ICT (MSIT), the '11' prefix is a non-geographic mobile code, meaning it is not tied to any specific physical region. Instead, it is allocated to mobile network operators (MNOs) and mobile virtual network operators (MVNOs) that provide nationwide cellular services. Historically, the 11 prefix was one of the first mobile codes introduced in South Korea, and it remains widely recognized, although number portability means that a subscriber retaining an 011 number may now be serviced by any carrier.

Dialing Format and Number Structure

South Korean mobile numbers using the 11 prefix follow the E.164 international format: +82 11 XXXX YYYY. The complete national significant number (NSN) is 10 digits, including the leading '0' that is dropped when dialing internationally. For example, a typical number might be written as 011-2345-6789 domestically, and as +82 11 2345 6789 from abroad. The prefix '11' is followed by an eight-digit subscriber number, which is further divided into a four-digit central office code and a four-digit line number. This structure provides ample capacity for millions of subscribers.

Calling Instructions

For callers within South Korea, dialing a mobile number with the 11 prefix requires the national trunk prefix '0' followed by '11' and the subscriber number. For instance, to call 011-2345-6789 from a local landline or another mobile, you would dial 011-2345-6789. When calling from outside South Korea, you must replace the leading '0' with the country code +82, resulting in +82 11 2345 6789 or 011 2345 6789 after dialing your country's international access code (e.g., 00 from most European countries, 011 from the US).

Carrier and Portability Considerations

Originally, the 11 prefix was exclusively used by SK Telecom, the country's largest MNO. However, with the introduction of mobile number portability (MNP) in 2004, subscribers can now switch carriers while retaining their existing number, including those starting with 11. Consequently, a number with the 11 prefix may currently be serviced by any of the three major MNOs (SK Telecom, KT, LG U+) or a range of MVNOs. This is important for businesses and individuals who rely on these numbers, as the prefix no longer indicates the network operator. For SMS and voice services, international routing to +82 11 numbers is handled seamlessly by global carriers, ensuring reliable connectivity.

Regulatory and Usage Notes

All mobile numbers in South Korea, including those with the 11 prefix, are considered non-geographic. They are not subject to local area code restrictions, and calls to them are typically charged at mobile rates, which may vary depending on the caller's plan. The MSIT periodically reviews numbering resources to ensure efficient utilization. As of recent years, the 11 prefix remains active and is not scheduled for retirement, though new mobile numbers are increasingly assigned with other prefixes such as 10, 16, 17, 18, and 19. For businesses, having a recognizable 011 number can still confer a sense of legacy and trust, but it is essential to verify the current carrier and service status through official databases or by contacting the number owner directly.