Benchmarked strictly across TripTiming's 5 empirical pillars: Crowds, Weather, Vibes, Prices, and Safety.
While New York City captures an advantage on pure Weather (99 vs 96) with 21°C ambient temperatures, London decisively captures September on Crowds (57 vs 35) and Prices (52 vs 50). New York City suffers from seasonal congestion and peak lodging premiums ($406/night), whereas London delivers a more balanced, friction-free itinerary with approximately $511 in lodging savings on a 7-night stay ($333/night vs $406/night).