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 → OAK flights land within a few points of 87% on time whatever the hour.

Nonstops


Southwest	ONT	OAK	1h 20m	87%	0.4%	1,471	Flying now

Best connections, one ticket

Most reliable Quickest (80%+ on time)

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


Alaska Details →	ONT 10:54 → PDX 13:09AS 1699	1h 59m Portland	PDX 15:08 → OAK 16:55AS 2035 · flown by Horizon	6h 01m	98%	96%
Southwest Details →	ONT 05:30 → LAS 06:35WN 3150	2h 00m Las Vegas	LAS 08:35 → OAK 10:10WN 1254	4h 40m	100%	92%
Delta Details →	ONT 17:21 → SLC 20:17DL 4443 · flown by SkyWest	2h 33m Salt Lake City	SLC 22:50 → OAK 23:50DL 3797 · flown by SkyWest	6h 30m	96%	91%
Southwest Details →	ONT 05:15 → PHX 06:30WN 864	3h 10m Phoenix	PHX 09:40 → OAK 11:35WN 2680	6h 20m	98%	90%
Delta Details →	ONT 09:40 → SLC 12:28DL 1302	2h 52m Salt Lake City	SLC 15:20 → OAK 16:23DL 3903 · flown by SkyWest	6h 43m	100%	90%
Delta Details →	ONT 06:00 → SLC 08:50DL 2708	1h 55m Salt Lake City	SLC 10:45 → OAK 11:53DL 4134 · flown by SkyWest	5h 53m	98%	90%
Alaska Details →	ONT 12:04 → SEA 14:44AS 654	2h 41m Seattle	SEA 17:25 → OAK 19:33AS 706	7h 29m	100%	72%
Southwest Details →	ONT 08:35 → LAS 09:40WN 2333	1h 10m Las Vegas	LAS 10:50 → OAK 12:30WN 322	3h 55m	92%	69%
Tight connection: often missed
Southwest Details →	ONT 14:30 → DEN 17:40WN 3147	1h 10m Denver	DEN 18:50 → OAK 20:25WN 1843	5h 55m	44%	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.

Morning

PHX · 1h 15m · leaves 05:15 2%

LAS · 1h 00m · leaves 05:30 3%

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.


American AA 1194 ONT 06:11 → PHX Southwest WN 2680 PHX 09:40 → OAK Connection details →	2h 10m	5h 24m	94%	86%
Alaska AS 345 ONT 07:00 → PDX Southwest WN 4928 PDX 12:25 → OAK Connection details →	3h 10m	7h 10m	100%	82%
Delta DL 4070 ONT 11:59 → SEA Alaska AS 706 SEA 17:25 → OAK Connection details →	2h 32m	7h 34m	95%	72%

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