717 nonstop flights · Aug 2025 – Jul 2026 · US DOT on-time records, all US airlines

No clear winner: United’s STL → IAD flights land within a few points of 77% on time whatever the hour.

Best time to leave 8–9 am 82% arrive on time from STL

Best single flight UA 4506 STL 08:43 → IAD 11:55 · 82% on time Avoid UA 4454 STL 12:55 → IAD 16:07 · 72% on time

Time of day × airport

Share of this route’s flights leaving within 15 minutes, by airport and scheduled departure hour, over Aug 2025 – Jul 2026. Blank: no flights then (or fewer than 40 in the year).

STL

% of this route’s flights leaving within 15 min (small number: flights in the Jun 6 – Jul 31, 2026 schedule): 85+75–8465–7455–64under 55

Pick an hour to see this route’s flights leaving then.

Airlines on this route

Arriving within 15 minutes. Regional flights count under the airline that sells them. Pick an airline to see its flights.


United (incl. GoJet, Republic)	717	77%	0.7%	137 min

Flights, best and worst

Flights in the Jun 6 – Jul 31, 2026 schedule that ran 150+ times in the year. Times are local. Pick a flight for its history.


UA 4506flown by GoJet	STL 08:43	IAD 11:55	82%
UA 4454flown by GoJet	STL 12:55	IAD 16:07	72%

Nonstops by airline and airport

Arriving within 15 minutes, Aug 2025 – Jul 2026. Pick a row to see that airline’s flights on that airport pair.


United	STL	IAD	2h 12m	77%	0.7%	717	Flying now

Flying on a particular day? Pick a date above and the same ranking uses our forecast odds for each flight that day: Tomorrow.

About this data: US DOT on-time records, Aug 2025 – Jul 2026, all US airlines; regional flights count under the airline that sells them. Schedules (which flights and connections exist, and their times) are as of Jun 6 – Jul 31, 2026; seasonal flights outside that window aren’t ranked. Rebuilt monthly. JSON