Understanding Phone Numbers in South Korea

Quick Reference

• Country: South Korea
• Country Code: +82
• International Prefix: 00(?:[125689]|3(?:[46]5|91)|7(?:00|27|3|55|6[126]))
• National Prefix: 0

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Overview

This comprehensive guide offers a detailed look into South Korea's telephone numbering system, including number formats, dialing procedures, and regulatory information. It is essential for telecom professionals, developers, and systems administrators to accurately implement South Korean phone number formats.

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Number Formats

General Number Structure

South Korea's phone numbers follow a national numbering plan managed by the Ministry of Science and ICT. The structure includes:

• Country Code: +82
• National Prefix: 0 (for domestic calls)
• Subscriber Number: Varies by service type (e.g., landline, mobile)

Number Structure Details

Service Type	Format	Example	Description
Geographic	0[2-6][0-9]{1,2}-[0-9]{3,4}-[0-9]{4}	02-1234-5678	Assigned by region, with the first digit indicating the area.
Mobile	010-[0-9]{4}-[0-9]{4}	010-1234-5678	Always starts with 010, followed by an 8-digit number.
Toll-Free	080-[0-9]{3,4}-[0-9]{4}	080-123-4567	Free from landlines, may incur charges from mobiles.
Premium Rate	060-[2-9][0-9]{6}	060-2123456	Used for specialized services like voting or adult content.
Emergency	1[0-9]{2}	119	Short codes for emergencies, such as 119 for fire and ambulance services.

Regular Expressions for Validation

• Geographic Numbers:
  ^0[2-6][0-9]{1,2}-[0-9]{3,4}-[0-9]{4}$
  

• Mobile Numbers:
  ^010-[0-9]{4}-[0-9]{4}$
  

• Toll-Free Numbers:
  ^080-[0-9]{3,4}-[0-9]{4}$
  

• Premium Rate Numbers:
  ^060-[2-9][0-9]{6}$
  

• Emergency Numbers:
  ^1[0-9]{2}$
  

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Dialing Procedures

Domestic Calls

• Landline to Landline: Dial the area code (with 0), then the subscriber number.
  • Example: 02-1234-5678
• Landline to Mobile: Dial 010, then the subscriber number.
  • Example: 010-1234-5678
• Mobile to Mobile: Dial the full number directly.
  • Example: 010-1234-5678

International Calls

• Outgoing: Dial 00, then the destination country code, area code, and subscriber number.
  • Example: To the US: 001-212-555-1234
• Incoming: Dial +82, then the local number without 0.
  • Example: +82-2-1234-5678

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Number Portability

Number portability in South Korea allows both mobile and fixed-line users to retain their numbers when switching providers. Introduced in 2004, this service enhances consumer flexibility.

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Major Telecom Operators and Number Ranges

Operator	Mobile Prefixes	Fixed-Line Prefixes
KT	010	02, 031, 032, etc.
LG U+	010	042, 043, 044, etc.
SK Telecom	010	051, 052, 053, etc.
SK Broadband	010	054, 055, 061, etc.

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Regulatory Body

The Ministry of Science and ICT oversees South Korea's telephone numbering plan. For current regulations, visit their official website.

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Technical Considerations

Number Allocation and Management

The MSIT strictly manages number allocation based on demand and service type, with specific prefixes designated for particular services (e.g., 010 for mobile).

Special Cases

• Golden Numbers: Highly sought after for their repeated digits, often auctioned or sold at a premium.
• Number Blocking: Certain numbers may be blocked for security, especially for international calls.

ITU-T Standards Compliance

South Korea complies with ITU-T standards E.123 and E.164, ensuring global compatibility.

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Conclusion

South Korea's telephone numbering system is robust and internationally compliant, meeting the needs of its highly connected population. Understanding its structure and regulations is crucial for effective communication within and beyond South Korea.