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 SMF → ONT flights land within a few points of 85% on time whatever the hour.

Nonstops


Southwest	SMF	ONT	1h 20m	85%	0.4%	2,115	Flying now

Best connections, one ticket

Most reliable Quickest (80%+ on time)

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


Alaska Details →	SMF 11:46 → PDX 13:18AS 621	1h 12m Portland	PDX 14:30 → ONT 16:52AS 2093 · flown by Horizon	5h 06m	100%	90%
Delta Details →	SMF 05:30 → SLC 08:11DL 1526	3h 08m Salt Lake City	SLC 11:19 → ONT 12:10DL 3172	6h 40m	99%	89%
Southwest Details →	SMF 05:10 → PHX 07:05WN 3815	3h 00m Phoenix	PHX 10:05 → ONT 11:20WN 431	6h 10m	98%	87%
Delta Details →	SMF 09:45 → SLC 12:26DL 1367	3h 19m Salt Lake City	SLC 15:45 → ONT 16:41DL 4443 · flown by SkyWest	6h 56m	99%	85%
Delta Details →	SMF 17:00 → SLC 19:43DL 1342	3h 16m Salt Lake City	SLC 22:59 → ONT 23:48DL 1614	6h 48m	98%	85%
Southwest Details →	SMF 06:15 → LAS 07:40WN 2178	3h 50m Las Vegas	LAS 11:30 → ONT 12:32WN 2298	6h 17m	100%	82%
Southwest Details →	SMF 05:25 → LAS 06:50WN 3784	2h 15m Las Vegas	LAS 09:05 → ONT 10:10WN 4179	4h 45m	96%	78%
United Details →	SMF 06:00 → SFO 06:54UA 1954	3h 46m San Francisco	SFO 10:40 → ONT 12:12UA 2661	6h 12m	100%	78%
Tight connection: often missed
United Details →	SMF 19:03 → SFO 20:10UA 5961 · flown by SkyWest	50m San Francisco	SFO 21:00 → ONT 22:37UA 552	3h 34m	31%	25%
Southwest Details →	SMF 16:35 → LAS 18:05WN 2221	1h 05m Las Vegas	LAS 19:10 → ONT 20:10WN 208	3h 35m	38%	21%
Southwest Details →	SMF 19:50 → LAS 21:20WN 1324	1h 05m Las Vegas	LAS 22:25 → ONT 23:32WN 2135	3h 43m	58%	13%

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.

Afternoon and evening

SLC · 57m · leaves 19:20 10%

PHX · 1h 10m · leaves 19:50 27%

SFO · 50m · leaves 19:03 69%

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 3773 SMF 05:55 → DEN United UA 430 DEN 11:25 → ONT Connection details →	2h 10m	6h 52m	100%	88%
Southwest WN 949 SMF 10:12 → PDX Alaska AS 2093 PDX 14:30 → ONT Connection details →	2h 48m	6h 40m	96%	88%
American AA 1867 SMF 06:00 → PHX Southwest WN 431 PHX 10:05 → ONT Connection details →	2h 11m	5h 20m	97%	85%

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