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

Connect in the morning. The same one-hour layover misses 4% of the time at 9 am and 43% of the time at 8 pm.

Nonstops (seasonal or thin)


United	SFO	STL	4h 11m	80%	1.4%	418	Flying now
Southwest	SFO	STL	3h 50m	47%	0.3%	342	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 2 h ahead of San Francisco). Layovers up to 4 hours. Pick a connection for the details.


Southwest Details →	SFO 05:10 → DEN 08:40WN 1424	1h 25m Denver	DEN 10:05 → STL 13:20WN 1753	6h 10m	96%	92%
United Details →	SFO 00:50 → ORD 07:16UA 1850	3h 24m Chicago	ORD 10:40 → STL 12:11UA 1355	9h 21m	100%	89%
Delta Details →	SFO 05:50 → SLC 08:42DL 1331	59m Salt Lake City	SLC 09:41 → STL 13:36DL 2455	5h 46m	96%	88%
Alaska Details →	SFO 07:03 → SEA 09:13AS 68	3h 53m Seattle	SEA 13:06 → STL 18:57AS 647	9h 54m	99%	86%
Delta Details →	SFO 22:55 → DTW 06:30DL 335	2h 20m Detroit	DTW 08:50 → STL 09:32 +1DL 2868	8h 37m	98%	86%
Alaska Details →	SFO 12:27 → SEA 14:35AS 630	3h 29m Seattle	SEA 18:04 → STL 23:59AS 615	9h 32m	98%	85%
American Details →	SFO 23:08 → ORD 05:29AA 2554	1h 36m Chicago	ORD 07:05 → STL 08:31 +1AA 4104 · flown by Envoy	7h 24m	89%	84%
United Details →	SFO 23:59 → IAH 06:04UA 505	1h 56m Houston	IAH 08:00 → STL 10:07 +1UA 6214 · flown by Mesa	8h 08m	96%	84%
Tight connection: often missed
American Details →	SFO 11:24 → MIA 20:05AA 2565	49m Miami	MIA 20:54 → STL 22:54AA 1594	9h 30m	47%	29%
American Details →	SFO 14:36 → ORD 21:26AA 2550	1h 34m Chicago	ORD 23:00 → STL 00:16 +1AA 1004	7h 40m	51%	27%
American Details →	SFO 11:24 → DFW 17:14AA 1849	47m Dallas-Fort Worth	DFW 18:01 → STL 19:52AA 2761	6h 28m	30%	16%

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

IAH · 1h 05m · leaves 05:00 3%

SLC · 59m · leaves 05:50 4%

DEN · 1h 00m · leaves 05:00 4%

Afternoon and evening

PHX · 48m · leaves 15:52 63%

DFW · 46m · leaves 15:37 74%

DEN · 1h 05m · leaves 14:35 90%

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 234 SFO 21:30 → DTW Southwest WN 1783 DTW 07:00 → STL Connection details →	1h 40m	8h 05m	94%	92%
United UA 582 SFO 06:00 → LAS Southwest WN 2369 LAS 11:10 → STL Connection details →	3h 24m	8h 25m	100%	90%
United UA 1708 SFO 07:00 → SEA Alaska AS 647 SEA 13:06 → STL Connection details →	3h 44m	9h 57m	100%	88%

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