In June 2018 the Federal Institute of Telecommunications announced a simplified version of Mexico’s numbering plan which was just introduced 3 days ago.
Basically, Mexico now uses a closed 10 digit numbering plan at a national level. No longer can local calls be dialed using just 7 or 8 digits. On the other hand, no extra codes must be added to any 10 digit number, mobile or landline, calling in from abroad or from within Mexico.
Changes to Mexico’s numbering plan beginning August 3, 2019:
Digit 1 will no longer be required in front of cell phone numbers when dialing Mexico from abroad
national dialing codes 044 and 045 which were required to dial calls to mobile numbers within Mexico have been dropped
for long distance calls within Mexico adding 01 in front of the area code is no longer necessary