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 1 time in 5 at 5 am and 38% of the time at 6 pm.

Nonstops


United	SFO	DEN	2h 40m	83%	0.2%	3,410	Flying now
Frontier	SFO	DEN	2h 49m	71%	0.8%	638	Flying now
Southwest	SFO	DEN	2h 30m	61%	0.8%	1,413	Flying now

Best connections, one ticket

Most reliable Quickest (80%+ on time)

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


United Details →	SFO 23:59 → IAH 06:04UA 505	2h 26m Houston	IAH 08:30 → DEN 10:05 +1UA 2816	9h 06m	98%	95%
United Details →	SFO 22:59 → SEA 01:29UA 5579 · flown by SkyWest	3h 31m Seattle	SEA 05:00 → DEN 08:43 +1UA 2601	8h 44m	100%	95%
United Details →	SFO 06:00 → LAS 07:46UA 582	1h 51m Las Vegas	LAS 09:37 → DEN 12:41UA 1315	5h 41m	100%	93%
United Details →	SFO 08:40 → SLC 11:49UA 5605 · flown by SkyWest	1h 16m Salt Lake City	SLC 13:05 → DEN 14:51UA 4720 · flown by SkyWest	5h 11m	100%	92%
United Details →	SFO 13:55 → LAX 15:35UA 2610	3h 10m Los Angeles	LAX 18:45 → DEN 22:15UA 2610	7h 20m	100%	91%
United Details →	SFO 06:00 → LAX 07:39UA 2127	3h 16m Los Angeles	LAX 10:55 → DEN 14:27UA 2061	7h 27m	100%	91%
United Details →	SFO 07:00 → SEA 09:22UA 1708	3h 28m Seattle	SEA 12:50 → DEN 16:42UA 1351	8h 42m	100%	89%
United Details →	SFO 08:50 → LAX 10:34UA 1896	2h 12m Los Angeles	LAX 12:46 → DEN 16:16UA 360	6h 26m	99%	89%
Tight connection: often missed
United Details →	SFO 10:15 → ACV 11:42UA 4708 · flown by SkyWest	48m Arcata/Eureka	ACV 12:30 → DEN 16:22UA 5966 · flown by SkyWest	5h 07m	60%	46%
American Details →	SFO 11:24 → DFW 17:14AA 1849	1h 16m Dallas-Fort Worth	DFW 18:30 → DEN 19:41AA 2235	7h 17m	63%	28%
American Details →	SFO 14:36 → ORD 21:26AA 2550	1h 08m Chicago	ORD 22:34 → DEN 00:17 +1AA 1387	8h 40m	40%	21%

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

LAX · 1h 08m · leaves 06:00 4%

PHX · 1h 20m · leaves 05:30 6%

SNA · 1h 18m · leaves 07:15 11%

Afternoon and evening

ORD · 47m · leaves 14:29 72%

AUS · 1h 10m · leaves 12:50 79%

DAL · 1h 00m · leaves 15:10 83%

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 1147 SFO 14:20 → SAN Alaska AS 1619 SAN 20:01 → DEN Connection details →	3h 54m	8h 10m	100%	96%
United UA 5579 SFO 22:59 → SEA Southwest WN 3615 SEA 05:15 → DEN Connection details →	3h 46m	8h 51m	99%	93%
Southwest WN 4231 SFO 05:00 → LAS United UA 1315 LAS 09:37 → DEN Connection details →	3h 02m	6h 41m	100%	93%

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