MCC and MNC Codes Explained: Complete Guide

MCC (Mobile Country Code) and MNC (Mobile Network Code) are numeric codes that uniquely identify mobile networks worldwide. These codes are essential for mobile devices to connect to the correct network and are used by apps like Signal Finder to identify and filter cell towers by carrier. This guide explains what these codes are, how they work, and how to use them.

What is MCC (Mobile Country Code)?

MCC is a three-digit code that identifies the country where a mobile network operates. It's part of the international standard for identifying mobile networks.

How MCC Works

• Three-digit numeric code (e.g., 310, 311, 312)
• Assigned by the International Telecommunication Union (ITU)
• Unique to each country
• Used in combination with MNC to identify networks

Common MCC Examples

What is MNC (Mobile Network Code)?

MNC is a two or three-digit code that identifies a specific mobile network operator within a country. Combined with MCC, it uniquely identifies a network globally.

How MNC Works

• Two or three-digit numeric code
• Unique within each country (identified by MCC)
• Assigned by national regulatory authorities
• Can have multiple MNCs for the same carrier (different networks, technologies)

MCC-MNC Combination

Together, MCC and MNC form a unique identifier for mobile networks:

Format

Why Both Codes Are Needed

• MCC identifies the country
• MNC identifies the carrier within that country
• Together they create a globally unique identifier
• Prevents conflicts between carriers in different countries

Common US Carrier Codes

Major US carriers and their MCC-MNC codes:

Verizon

AT&T

T-Mobile

Sprint (now part of T-Mobile)

Why Carriers Have Multiple Codes

Carriers often have multiple MCC-MNC codes for various reasons:

Different Technologies

• Separate codes for 2G, 3G, 4G, 5G networks
• Legacy systems may use different codes
• Network evolution over time

Acquisitions and Mergers

• Acquired carriers keep their original codes
• Merged networks may use multiple codes
• Gradual migration to unified codes

Regional Variations

• Different codes for different regions
• Network optimization
• Regulatory requirements

How Signal Finder Uses MCC-MNC Codes

Signal Finder uses MCC-MNC codes to identify and filter cell towers:

Network Identification

• Identifies which carrier operates each tower
• Shows network information in tower details
• Helps distinguish between carriers

Advanced Search (Premium Feature)

Premium users can search by MCC-MNC codes:

• Filter towers by specific carrier codes
• Find networks with specific codes
• Identify carrier networks precisely

How to Find MCC-MNC Codes

Several ways to find MCC-MNC codes:

Using Signal Finder

1. Open Signal Finder app
2. Tap on a cell tower marker
3. View tower details
4. MCC-MNC codes are displayed in the information

Online Databases

• ITU maintains official MCC lists
• Various online databases list MNC codes
• Carrier websites may provide information

Field Test Mode (iOS)

iPhone users can access Field Test Mode:

1. Dial *3001#12345#* and press call
2. Navigate to network information
3. Find MCC and MNC values

Practical Applications

Network Troubleshooting

• Identify which network you're connected to
• Verify carrier information
• Debug connection issues

Roaming

• Identify networks when traveling
• Understand which networks your device can use
• Verify roaming partner networks

Network Analysis

• Map carrier coverage
• Compare network deployments
• Research network infrastructure

Technical Details

Code Assignment

• MCC assigned by ITU
• MNC assigned by national authorities
• Codes are registered and maintained
• Changes require official approval

Format Variations

• MNC can be 2 or 3 digits
• Leading zeros may be included or omitted
• Display format can vary

Common Questions

Can MCC-MNC Codes Change?

Yes, but rarely. Codes can change due to:

• Carrier mergers
• Regulatory changes
• Network restructuring

Are Codes the Same Worldwide?

No. The same carrier may have different codes in different countries. For example, T-Mobile in the US has different codes than T-Mobile in Germany.

Do All Towers Show MCC-MNC?

Most modern towers broadcast MCC-MNC information, but some older or specialized towers may not display this information clearly.

Conclusion

MCC and MNC codes are fundamental to mobile network identification, allowing devices and apps to correctly identify and connect to networks. Understanding these codes helps you better use tools like Signal Finder to identify carriers, troubleshoot connections, and analyze network coverage. Whether you're a casual user curious about network information or a network professional, MCC-MNC codes provide valuable insights into mobile network infrastructure.