Dialing within Mexico:
Land line to local land line phone - dial the seven digit number (i.e. 143-1234)
Land line to long distance land line phone - dial 01 then the ten digit number (i.e. 01-612-123-1234)
Land line to local cell phone - dial 044 then the ten digit number (i.e. 044-624-122-1234)
Land line to long distance cell phone - dial 045 then the ten digit number (i.e. 045-612-123-1234)
Cell phone to local or long distance land line - dial the ten digit number (i.e. 624-143-1234)
Cell phone to local or long distance cell phone - dial the ten digit number (i.e. 612-122-1234)

Dialing into Mexico:
To dial a land line phone - Dial 011-52 then the ten digit number (i.e. 011-52-624-143-1234)
To dial a cell phone - Dial 011-52-1 then the ten digit number (i.e. 011-52-1-624-122-1234)

Dialing from Mexico to the US/Canada
Dial 001 then the ten digit number (i.e. 001-303-333-3333)

Dialing from Mexico to the rest of the world
Dial 00 then the Country Code and phone number

Dialing US Toll Free Numbers
For 800 numbers - dial 001-880 then the seven digit number
For 866 numbers - dial 001-883 then the seven digit number
For 877 numbers - dial 001-882 then the seven digit number
For 888 numbers - dial 001-881 then the seven digit number

List of Mexico's newly updated Area Codes

Telephone numbers below updated 12/18/2014

American Society of Mexico: 011-52 (55) 5277-5875
     Information from Americans who are living in Mexico.
Association of Mexican Banks: 011-52 (55) 5722-4300
Mexican Automotive Industry Association: 011-52 (55) 5272-1144
Border Trade Alliance: U.S. (202) 386-9653
      Promoting trade along the U.S.-Mexico border.
Canacintra: 011-52 (55) 5482-3000
      The Mexican National Chamber of Industry & Manufacturing.
Consulates of Mexico, in the United States & Canada.
Embassies & Chambers of Commerce, both of Mexico & various other nations.
FONATUR: 011-52 (55) 5090-4200
     Offering foreign investment in Mexico's tourism industry.
Mexican Association of Realtors - AMPI: 011-52 (55) 5566-4260
     Most real estate office belong to this association.
Mexican Franchise Association: 011-52 (55) 5661-2040
      Provides information about franchising in Mexico.
Mexican Government Tourism: U.S. (800) 44-MEXICO
      The Department of Tourism offering information on Mexico.
Missing Persons Hotline in Mexico (Províctima): 011-52 (55) 1000-2000
National Museum of Anthropology: 011-52 (55) 4040-5300
PROFECO (Consumer Protection): 011-52 (55) 5568-8722
      Protects foreign tourists & residents.
PROMEXICO: 011-52 (55) 5447 7070
      Supporting international business & investment in Mexico.
San Antonio Economic Development Foundation: U.S. (210) 226-1394
      Develops and promotes trade with Mexico.
SEMARNAT: 011-52 (55) 5490-0900 Secretary of the Environment & Natural Resources.
State Tourism Offices in Mexico, provides information on particular states.
United States-Mexico Chamber of Commerce: U.S. (703) 752-4751
      promoting business between the U.S. and Mexico..
World Trade Center of Mexico City: 011-52 (55) 9000-6000
      Business center & exposition area.