One of the survivors had been an eight-year-old girl.
The bus was speeding when it crashed through a barrier and plummeted over a 200-meter cliff on the Mexico City-Veracruz highway.
Sixty-three bodies were discovered at the crash site and three survivors, including the girl, were taken unconscious to area hospitals, officials said earlier.
The dead, including some 10 children, were all Mexicans.
Ranulfo Marquez Hernandez, the deputy police chief of Veracruz state, told reporters that the coach was carrying far more than the 50 passengers it was designed for.
Searches would continue, although there was now little chance of finding more survivors, he said.
Preliminary investigations indicated that there was a mechanical fault on the coach, leaving the bus without brakes at a crucial stage.
Every year, traffic accidents claim dozens of lives in Mexico during the busy April vacation period. Enditem