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

No clear winner: Southwest’s ONT → SMF flights land within a few points of 86% on time whatever the hour.

Nonstops


Southwest	ONT	SMF	1h 25m	86%	0.3%	2,114	Flying now

Best connections, one ticket

Most reliable Quickest (80%+ on time)

Ranked by chance you reach Sacramento on time. Total trip = scheduled departure to arrival, layover included. Layovers up to 4 hours. Pick a connection for the details.


Southwest Details →	ONT 05:30 → LAS 06:35WN 3150	2h 00m Las Vegas	LAS 08:35 → SMF 10:05WN 860	4h 35m	100%	94%
Southwest Details →	ONT 05:15 → PHX 06:30WN 864	1h 15m Phoenix	PHX 07:45 → SMF 09:45WN 2885	4h 28m	98%	92%
Alaska Details →	ONT 07:00 → PDX 09:15AS 345	1h 45m Portland	PDX 11:00 → SMF 12:33AS 2399 · flown by Horizon	5h 33m	100%	91%
Delta Details →	ONT 17:21 → SLC 20:17DL 4443 · flown by SkyWest	2h 47m Salt Lake City	SLC 23:04 → SMF 23:44DL 1582	6h 27m	96%	85%
Delta Details →	ONT 11:59 → SEA 14:53DL 4070 · flown by SkyWest	2h 07m Seattle	SEA 17:00 → SMF 19:01DL 4043 · flown by SkyWest	7h 02m	96%	85%
Delta Details →	ONT 06:00 → SLC 08:50DL 2708	2h 45m Salt Lake City	SLC 11:35 → SMF 12:16DL 1423	6h 21m	98%	84%
Delta Details →	ONT 06:20 → SEA 09:17DL 3816 · flown by SkyWest	53m Seattle	SEA 10:10 → SMF 12:18DL 4125 · flown by SkyWest	5h 58m	93%	84%
Southwest Details →	ONT 08:35 → LAS 09:40WN 2333	1h 45m Las Vegas	LAS 11:25 → SMF 13:00WN 4532	4h 25m	98%	84%
Tight connection: often missed
Alaska Details →	ONT 17:26 → SEA 20:06AS 575	49m Seattle	SEA 20:55 → SMF 22:48AS 1427	5h 22m	41%	29%
Southwest Details →	ONT 14:30 → DEN 17:40WN 3147	1h 45m Denver	DEN 19:25 → SMF 20:55WN 136	6h 25m	71%	6%

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

DEN · 1h 15m · leaves 05:50 2%

PHX · 1h 15m · leaves 05:15 2%

SEA · 1h 17m · leaves 06:02 5%

Afternoon and evening

SEA · 49m · leaves 17:26 59%

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 3144 ONT 05:50 → DEN United UA 1415 DEN 11:30 → SMF Connection details →	2h 25m	7h 15m	100%	82%
Alaska AS 654 ONT 12:04 → SEA Delta DL 4043 SEA 17:00 → SMF Connection details →	2h 16m	6h 57m	96%	82%
American AA 1194 ONT 06:11 → PHX Southwest WN 781 PHX 09:35 → SMF Connection details →	2h 05m	5h 19m	93%	81%

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