Benchmarked strictly across TripTiming's 5 empirical pillars: Crowds, Weather, Vibes, Prices, and Safety.
Mallorca emerges as the optimal September destination with an overall TripTiming Index of 70/100 vs 69/100 for Ibiza (+1 point advantage). Mallorca experiences substantially lower visitor footfall and shorter landmark queues (moderate footfall vs heavy visitor congestion in Ibiza). This is reinforced by lower lodging rates (~$322/night vs ~$406/night, saving ~$588 over 7 nights).