Itineraries flown on 20+ days in the Jun 6 – Jul 31, 2026 schedule · each leg’s record Aug 2025 – Jul 2026

Connect in the morning. The same one-hour layover misses 7% of the time at 9 am and 65% of the time at 9 pm.

Nonstops


Frontier	DEN	STL	2h 12m	85%	0.3%	291	Flying now
United	DEN	STL	2h 09m	80%	0.3%	1,210	Flying now
Southwest	DEN	STL	2h 05m	77%	0.5%	2,194	Flying now

Best connections, one ticket

Most reliable Quickest (80%+ on time)

Ranked by chance you reach St Louis on time. Total trip = scheduled departure to arrival, layover included (St Louis is 1 h ahead of Denver). Layovers up to 4 hours. Pick a connection for the details.


Southwest Details →	DEN 07:40 → LAS 08:35WN 1559	2h 35m Las Vegas	LAS 11:10 → STL 16:25WN 2369	7h 45m	100%	90%
Delta Details →	DEN 05:40 → SLC 07:13DL 2544	2h 28m Salt Lake City	SLC 09:41 → STL 13:36DL 2455	6h 56m	97%	88%
Southwest Details →	DEN 07:45 → MCI 10:25WN 1584	3h 20m Kansas City	MCI 13:45 → STL 14:50WN 2083	6h 05m	100%	88%
American Details →	DEN 23:59 → CLT 05:13AA 3156	2h 23m Charlotte	CLT 07:36 → STL 08:32 +1AA 2733	7h 33m	98%	87%
Delta Details →	DEN 00:40 → ATL 05:42DL 302	2h 01m Atlanta	ATL 07:43 → STL 08:19DL 1571	6h 39m	99%	87%
Delta Details →	DEN 07:15 → ATL 12:12DL 431	1h 57m Atlanta	ATL 14:09 → STL 14:48DL 2700	6h 35m	97%	85%
Southwest Details →	DEN 23:55 → MCO 05:40WN 1597	1h 10m Orlando	MCO 06:50 → STL 08:20 +1WN 2570	7h 25m	85%	85%
Delta Details →	DEN 00:59 → DTW 05:48DL 1096	3h 02m Detroit	DTW 08:50 → STL 09:32DL 2868	7h 33m	97%	85%
Tight connection: often missed
United Details →	DEN 15:01 → ORD 18:46UA 1023	1h 09m Chicago	ORD 19:55 → STL 21:26UA 2144	5h 25m	73%	45%
American Details →	DEN 17:57 → ORD 22:00AA 1734	1h 00m Chicago	ORD 23:00 → STL 00:16 +1AA 1004	5h 19m	54%	27%
United Details →	DEN 09:43 → SFO 11:25UA 1506	47m San Francisco	SFO 12:12 → STL 18:17UA 2090	7h 34m	32%	24%

Same layover, different day-part

How often the first flight arrives too late to connect (45 min minimum), for one-ticket layovers of 45–80 minutes.

Morning

MDW · 1h 12m · leaves 05:55 0%

ATL · 1h 10m · leaves 05:45 4%

DFW · 1h 14m · leaves 06:20 6%

Afternoon and evening

MSP · 1h 00m · leaves 13:42 50%

DFW · 52m · leaves 18:10 65%

PHX · 1h 05m · leaves 18:55 67%

Delays build through the day, so an afternoon first leg eats the layover. A short connection is fine early in the morning and a gamble later on.

Mixing airlines

One ticketMiss it and the airline rebooks you; bags go through. 45 min is enough.

Separate ticketsMiss it and you buy a new ticket. Re-check bags, clear security again: we require 90 min.


United UA 5247 DEN 08:00 → MCI Southwest WN 2083 MCI 13:45 → STL Connection details →	2h 55m	5h 50m	100%	88%
United UA 2316 DEN 08:05 → LAS Southwest WN 2369 LAS 11:10 → STL Connection details →	2h 03m	7h 20m	97%	87%
Frontier F9 3294 DEN 06:30 → ATL Delta DL 2700 ATL 14:09 → STL Connection details →	2h 31m	7h 20m	97%	86%

Rank all connections, any airlines →

Regional partners count as the airline that sells them: SkyWest flying Delta Connection is one Delta ticket.

How these are worked out. Makes the connection: share of the last year’s flights where the first flight arrived with at least 45 minutes to spare (90 on separate tickets). Arrives on time: first flight not cancelled × connection made × second flight not cancelled and arriving within 15 minutes. Not yet counted: the second flight also leaving late (which helps), gate-to-gate distance at the hub, and rebooking after a missed connection.

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