IAD → STL: cancellations & delays
Over Jan 2023 - Apr 2026, 0.5% of Washington Dulles International Airport (IAD) to St. Louis Lambert International Airport (STL) flights were cancelled and 11.7% arrived at least 15 minutes late, across 206 flights, flown by YX. Cancellations peak in September.
Check today's live IAD departures →Airport pages: Washington Dulles International Airport (IAD) · St. Louis Lambert International Airport (STL)
Rates are historical averages from U.S. DOT (BTS) on-time records; a specific flight's live estimate can differ with weather and the day's disruptions.