Area Code 311 – Mobile Network

Overview of Colombia's Mobile Prefix 311

In Colombia, the national numbering plan adheres to the ITU-T E.164 standard, with a country calling code of +57. Mobile numbers are non-geographic and are identified by a three-digit mobile prefix that follows the country code. The prefix 311 is allocated to mobile services, indicating that the subscriber is associated with a mobile network operator (MNO) or mobile virtual network operator (MVNO). Unlike geographic area codes, 311 does not correspond to a specific city or region; it is valid nationwide. This means that a number formatted as +57 311 XXX XXXX can belong to a user located anywhere in Colombia, from Bogotá to Medellín or rural areas.

Number Structure and Dialing Formats

Colombian mobile numbers consist of the country code +57, followed by a three-digit mobile prefix (e.g., 311) and a seven-digit subscriber number. The complete international format is +57 311 XXX XXXX, totaling 12 digits when including the country code. When dialing domestically, callers must include the prefix and the seven-digit number, resulting in a ten-digit national significant number: 311 XXX XXXX. It is important to note that Colombia uses a closed dialing plan; there is no trunk prefix like '0' for domestic calls. Therefore, to call a 311 number from within Colombia, you simply dial 311 XXX XXXX. From abroad, you dial +57 311 XXX XXXX (or 0057 311 XXX XXXX from countries using the international prefix 00).

Carrier Assignment and Number Portability

The 311 prefix was originally assigned to Comcel, now operating under the brand Claro, one of Colombia's largest mobile operators. However, due to mobile number portability (MNP), subscribers may retain their 311 number even if they switch to another carrier, such as Movistar, Tigo, or a smaller MVNO. Consequently, while 311 numbers are historically associated with Claro, the actual current carrier can vary. For verification, users can query the number's operator through official databases or contact the number directly.

Usage and Considerations

311 numbers are used for voice calls, SMS, and mobile data services. They are also commonly used for two-factor authentication (2FA) and business communications. When calling a 311 number from a landline or another mobile, standard call charges apply as per the caller's plan. For international callers, rates vary by provider, but the call is routed as a mobile termination. It is essential to ensure that the correct number of digits is dialed; omitting the leading 3 or adding extra digits will result in a failed call. For SMS, the same international format is used, and messages are delivered to the mobile network.