To save up to 56% on this flight, we recommend booking at least 61 days prior to travel. The price may fluctuate and will likely increase closer to your departure date. Users on Cheapflights have found tickets from Cancún to Puerto Rico from $337 1-2 weeks out and tickets from $422 for flights departing within the next 72 hours.
Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Cancún to Puerto Rico as you normally would.