Mexico Changes to 10-Digit Telephone Dialing on August 3, 2019 Team Angels - Wikipedia
go to original July 24, 2019

As of August 3, 2019, phone numbers in Mexico will become ten digits by appending the area codes to the local number. After this date, all phone numbers should be dialed in a ten-digit format, even for local calls.

For long distance calls within Mexico, it will no longer be required to dial 01 before the area code and telephone number.

The change will also eliminate the 044 or 045 when calling a cell phone in Puerto Vallarta or Riviera Nayarit, therefore, to call a cellular phone, it will now be the same as calling a land line.

International calls from the United States or Canada to Mexico will be the same as before (011-52 + three digit area code + seven digit phone number).

Telephone calls from Mexico to the U.S. and Canada will remain the same.

For your convenience, the following services can be dialed with three digit numbers:

#         Services
020    Operator-assisted domestic collect call (Telmex)
030    Local time (Telmex)
031    Wake up service
040    Information / directory
050    Phone company hotline
051    Number portability PIN (can be used to determine your own line's phone number)
070    City hotline (not available in some cities)
071    CFE hotline (electric company)
072    [Reporte de Servicios de Ciudad] hotline (Water Troubles, Bad Road, Etc... not available in some cities)
090    Operator-assisted international collect call
911    Emergency telephone number (since 2016)

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