I do not want to argue nor to I make any claims about knowing the facts. On the websites I have found about Hoy no Circula they state there are 18 municipios in Mexico State which are in the zone. Other websites state there are a total of 125 municipios in Mexico State. To me that indicates there are 107 municipios in Mexico State which are not in the zone. Here are some of the websites where you can find information.
http://www.paisano.gob.mx/index.php/paso-a-paso-tu-viaje/69-hoy-no-circula
Si visitas la Ciudad de México o el Área Metropolitana, tienes que cumplir con el Programa Hoy No Circula, el cual opera en el Distrito Federal y 18 municipios del Estado de México, de lunes a sábado de las 05:00 a las 22:00 horas, y que prohíbe la circulación de vehículos de acuerdo con el último número de placa de tu vehículo. Asimismo, funciona de lunes a viernes de las 05:00 a las 11:00 horas si tus placas son foráneas o extranjeras:
Google Translate
If you visit Mexico City and the metropolitan area, you have to meet the program Hoy No Circula, which operates in the Federal District and 18 municipalities in the State of Mexico, Monday to Saturday 05:00 to 22:00 hours and prohibiting the movement of vehicles according to the latest issue of your vehicle plate. It also operates Monday through Friday from 05:00 to 11:00 hours if your plates are foreign or foreign:
http://www.hoy-no-circula.com.mx/
La cobertura del programa incluye las 16 delegaciones del Distrito Federal y los 18 municipios conurbanos de Estado de México. Esto significa que su área de aplicación comprende:
Google Translate
Program coverage includes the 16 delegations of the Federal District and 18 municipalities conurbations State of Mexico. This means that your application area includes:
Álvaro Obregón
Azcapotzalco
Benito Juárez
Coyoacán
Cuajimalpa de Morelos
Cuauhtémoc
Gustavo A. Madero
Iztacalco
Iztapalapa
La Magdalena Contreras
Miguel Hidalgo
Milpa Alta
Tláhuac
Tlalpan
Venustiano Carranza
Xochimilco
Atizapán de Zaragoza
Coacalco
Cuautitlán
Cuautitlán Izcalli
Chalco
Chimalhuacán
Ecatepec de Morelos
Huixquilucan
Ixtapaluca
La Paz
Naucalpan de Juárez
Nezahualcóyotl
Chicoloapan
Nicolás Romero
Tecámac
Tlalnepantla de Baz
Tultitlán
Valle de Chalco
http://www.eluniversal.com.mx/articulo/metropoli/edomex/2016/04/4/enterate-municipios-del-edomex-donde-aplica-el-hoy-no-circula
http://data.sedema.cdmx.gob.mx/sedema/index.php/verificacion-hoy-no-circula/hoy-no-circula/objetivo-y-aplicacion-del-programa-hoy-no-circula
This website (below) lists all 125 of the municipios in Mexico State. I am no authority – just trying to find information that may be of use. I believe perhaps confusion might be due to the fact that much of Distrito Federal is in the zone but that is not Mexico State – though it is a huge part within the area of Mexico State. It does appear not all of Mexico State is in the zone. These are just a few of the many websites where more can be learned about Hoy no Circula. Though Teotihuacan (and many other municipios) is in Mexico State it does not appear on the list of municipios in the zone.
http://www.soymexiquense.com/edomex/municipios
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