El Ejido Llano Blanco (Rancho Seco) belongs to the municipality Altar, Sonora state and its official ZIP Code is 83794
The Postal Codes National Catalog is prepared by the Mexican Postal Service and the postal code has 5 digits, depending on the country area. The first two digits identify the state or part of it. In the case of Altar the Zip Code range of the Sonora state is 83 a 85. To send letters or packages to Altar, Sonora you must always use the five-digit postal code.
The local area phone code is 637
Check out the Sonora ZIP Code list
Check out the list of cities with 83794 ZIP Code in México