Area Code 317 – Minas Gerais

Overview of Area Code 317 (Brazil)

Area code 317 is a geographic National Destination Code (NDC) assigned to the central region of the state of Minas Gerais, Brazil. It is part of the Brazilian telephone numbering plan, which follows ITU-T E.164 recommendations. The code serves a significant portion of the state, including its capital, Belo Horizonte, and the surrounding metropolitan area. This region is one of the most economically and demographically important in Brazil, with a high density of fixed and mobile telecommunications infrastructure.

Geographic Coverage and Jurisdiction

The 317 area code covers the central-southern part of Minas Gerais, encompassing the capital and numerous neighboring municipalities. Key cities within this code include Belo Horizonte, Contagem, Betim, Nova Lima, and Santa Luzia. The administrative jurisdiction is the state of Minas Gerais, and the code is managed by the Brazilian National Telecommunications Agency (ANATEL). The region is served by a mix of incumbent and competitive carriers, offering PSTN, VoIP, and mobile services.

Dialing Formats

For local calls within the same area code, Brazilian users typically dial only the eight-digit subscriber number (e.g., 3123-4567). For calls from other area codes within Brazil, the full national format is used: 0 + carrier code + 31 + subscriber number (e.g., 0 15 31 3123-4567). International callers must dial the Brazilian country code (+55), then the area code 31, followed by the subscriber number, without the leading trunk prefix. For example, a call from the United States to a fixed line in Belo Horizonte would be dialed as 011 55 31 3123-4567.

Overlay and Numbering Considerations

Currently, area code 31 is not overlaid with another code; it is the sole geographic code for the region. However, due to growing demand, ANATEL has implemented number pooling and other measures to ensure sufficient numbering resources. Subscriber numbers in this area are eight digits long, and mobile numbers within the same geographic region also use the 31 code, but they are identified by their initial digit (typically 9 for mobile). This distinction is crucial for routing and billing purposes.

Caller Instructions

For local callers, simply dial the eight-digit number. For long-distance callers within Brazil, you must select a carrier code (e.g., 15 for Vivo, 21 for Embratel) and dial the full national format. International callers should note that Brazil uses a variable-length numbering plan, and the area code is essential for routing. Always include the country code and area code when dialing from abroad. For mobile numbers, the same area code applies, but you must include the mobile prefix (9) as part of the subscriber number.