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Who assigns MCC and MNC codes?
The ITU allocates MCCs under Recommendation ITU-T E.212, and each country's numbering authority — usually the telecom regulator — assigns MNCs to the operators it licenses. A large country can hold more than one MCC when it runs out of network codes.
Where are MCC and MNC codes used?
They form the first five or six digits of every IMSI, the subscriber identity stored on the SIM, so a network knows which home operator a SIM belongs to. Together they make up the PLMN ID that networks broadcast and phones search for when roaming. Messaging platforms use the pair as the operator key in routing tables, price lists and number-lookup results, because one country code can map to several operators.
Is the MNC the same as the phone number prefix?
No. The MNC belongs to the network, not to the number. With number portability a subscriber keeps their number when they move to another operator, so the dialling prefix no longer shows which network serves it. An HLR or number-portability lookup returns the current MCC-MNC, which is how a provider routes a message to the right operator and prices it correctly.
How can I look up an MCC or MNC?
BroadNet's free MCC/MNC lookup tool lists the codes by country and operator, and an HLR lookup returns the live MCC-MNC for an individual number. The protocol reference on MCC, MNC and PLMN codes covers the numbering background in more depth.