Benchmarked strictly across TripTiming's 5 empirical pillars: Crowds, Weather, Vibes, Prices, and Safety.
While Cancun captures an advantage on pure Weather (87 vs 81) with 32°C ambient temperatures, San Juan decisively captures October on Crowds (76 vs 68) and Prices (75 vs 80). Cancun suffers from seasonal congestion and peak lodging premiums ($189/night), whereas San Juan delivers a more balanced, friction-free itinerary with approximately $112 in lodging savings on a 7-night stay ($173/night vs $189/night).