Area Code 623 – Sonora
The phone area code for Sonora is 623 (international format +52623). Browse local exchange codes (NXX) and carrier assignments below.
📞 Exchange Codes (NXX) for Area Code 623
Select a central office code to view local carrier data and detailed information
📍 Geographic Location of Sonora
Geographic Coverage and Administrative Jurisdiction
Area code 623 is a geographic National Destination Code (NDC) assigned to the state of Sonora, Mexico, under the country calling code +52. This code serves the central and southern municipalities of Sonora, including the state capital Hermosillo, as well as nearby cities and towns such as Guaymas, Empalme, and San Carlos. The numbering area encompasses both urban and rural zones, with Hermosillo being the primary economic and administrative hub. As a geographic code, 623 is tied to a specific physical region, and calls are routed based on the destination's location within Sonora.
Dialing Formats and Caller Instructions
For callers within Mexico, dialing a 623 number requires the national long-distance prefix 01, followed by the area code and the seven-digit local number. For example, to reach a landline in Hermosillo, you would dial: 01 623 123 4567. For international callers, the format is +52 623 123 4567 (or 011 52 623 123 4567 from the US/Canada). When dialing locally within the same area code, the seven-digit number alone may suffice, but it is always safe to use the full national format. Note that Mexico has implemented overlay codes in some regions, but as of now, 623 is the sole geographic code for this area, so no overlay dialing changes are required.
Numbering and Routing Considerations
All landline numbers under 623 consist of seven digits, with the first digit typically between 2 and 9, excluding 0 and 1. The code is managed by the Federal Telecommunications Institute (IFT) and assigned to various carriers, including Telmex and other local operators. Calls to 623 numbers are routed over the PSTN, and while some VoIP services may be used, the geographic nature of the code means that the physical location of the line is fixed. This is important for emergency services and for businesses that rely on local presence. For callers outside Mexico, it is essential to use the correct international prefix and to omit the leading '01' that is used domestically.
Practical Examples for Businesses and Travelers
If you are a business establishing a presence in Sonora, obtaining a 623 number can enhance local trust and accessibility. For instance, a customer in the US calling your Hermosillo office would dial 011 52 623 456 7890. Conversely, if you are traveling within Mexico and need to call a local restaurant in Guaymas, you would dial 01 623 456 7890. Always verify the complete number, as seven-digit local numbers are unique within the 623 area. For further assistance, consult your telecom provider or the official IFT numbering plan.