Alvaro Vizcaino, executive secretary of the National Public Security System, said the new number began in 16 states and will be adopted in the country's 16 other federal entities in January.
"Eight in 10 Mexicans already have a reference to 911, the majority through television series and films," Vizcaino said at a news conference, adding that it was the reason that it was chosen.
Emergency numbers vary from state to state in Mexico. The 911 number is used in the United States, Canada and some other countries. President Enrique Pena Nieto had announced in November 2014 plans to adopt the 911 number as part of an overhaul of the country's law enforcement system.
Authorities have repeatedly urged Mexicans to denounce crimes, amid fears of reprisals in parts of the country where drug cartels terrorize populations.