Sun, Oct 4 has passed, so this is the 12-month record.

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

No clear winner: airlines and hours on this route all land within a few points of 88% on time.

Nonstops (seasonal or thin)


Delta	STL	SLC	3h 13m	88%	0.9%	981	Flying now
Southwest	STL	SLC	–	67%few flights	0.0%	9	Not flying now

Best connections, one ticket

Most reliable Quickest (80%+ on time)

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


Delta Details →	STL 06:00 → ATL 08:38DL 1524	1h 27m Atlanta	ATL 10:05 → SLC 12:10DL 387	7h 10m	98%	88%
Delta Details →	STL 08:49 → MSP 10:30DL 5325 · flown by Endeavor	1h 59m Minneapolis	MSP 12:29 → SLC 14:22DL 2651	6h 33m	97%	87%
United Details →	STL 05:10 → DEN 06:32UA 362	1h 28m Denver	DEN 08:00 → SLC 09:37UA 497	5h 27m	97%	86%
Delta Details →	STL 07:08 → ATL 09:45DL 1536	2h 09m Atlanta	ATL 11:54 → SLC 13:50DL 663	7h 42m	98%	84%
Delta Details →	STL 06:30 → DTW 09:04DL 1626	3h 21m Detroit	DTW 12:25 → SLC 14:19DL 935	8h 49m	97%	84%
United Details →	STL 09:06 → DEN 10:30UA 2459	3h 10m Denver	DEN 13:40 → SLC 15:13UA 1840	7h 07m	99%	83%
Delta Details →	STL 09:24 → ATL 12:02DL 1571	1h 53m Atlanta	ATL 13:55 → SLC 15:51DL 423	7h 29m	98%	81%
United Details →	STL 06:00 → ORD 07:30UA 2805	1h 25m Chicago	ORD 08:55 → SLC 11:39UA 1972	6h 39m	97%	81%
Tight connection: often missed
American Details →	STL 08:37 → DFW 10:37AA 3194	53m Dallas-Fort Worth	DFW 11:30 → SLC 13:10AA 2613	5h 33m	67%	38%
American Details →	STL 17:13 → DFW 19:15AA 2712	1h 55m Dallas-Fort Worth	DFW 21:10 → SLC 22:59AA 2993	6h 46m	56%	23%
Southwest Details →	STL 18:40 → DEN 20:00WN 3913	55m Denver	DEN 20:55 → SLC 22:40WN 1737	4h 55m	43%	17%

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

DFW · 1h 08m · leaves 05:30 6%

CLT · 57m · leaves 05:10 7%

DEN · 1h 10m · leaves 09:06 8%

Afternoon and evening

MSP · 1h 05m · leaves 17:36 26%

DEN · 55m · leaves 18:40 57%

PHX · 1h 00m · leaves 19:20 60%

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.


Southwest WN 3967 STL 05:45 → PHX Delta DL 1447 PHX 09:45 → SLC Connection details →	2h 50m	7h 38m	100%	93%
Southwest WN 4780 STL 08:25 → MSY Delta DL 736 MSY 13:30 → SLC Connection details →	3h 20m	8h 43m	98%	90%
Southwest WN 3937 STL 08:10 → LAX United UA 5371 LAX 12:55 → SLC Connection details →	2h 50m	8h 38m	100%	89%

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