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

No clear winner: airlines and hours on this route all land within a few points of 92% on time.

Nonstops


Delta	ONT	SLC	1h 50m	92%	0.9%	1,209	Flying now
Frontier	ONT	SLC	1h 48m	90%few flights	0.0%	30	Not flying now

Best connections, one ticket

Most reliable Quickest (80%+ on time)

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


Southwest Details →	ONT 05:15 → PHX 06:30WN 864	1h 15m Phoenix	PHX 07:45 → SLC 10:25WN 3339	4h 10m	98%	95%
Alaska Details →	ONT 10:54 → PDX 13:09AS 1699	1h 21m Portland	PDX 14:30 → SLC 17:29AS 3120 · flown by SkyWest	5h 35m	98%	92%
Alaska Details →	ONT 07:00 → PDX 09:15AS 345	1h 40m Portland	PDX 10:55 → SLC 13:59AS 3112 · flown by SkyWest	5h 59m	100%	92%
United Details →	ONT 06:00 → SFO 07:25UA 2363	1h 15m San Francisco	SFO 08:40 → SLC 11:49UA 5605 · flown by SkyWest	4h 49m	96%	90%
Southwest Details →	ONT 05:30 → LAS 06:35WN 3150	1h 00m Las Vegas	LAS 07:35 → SLC 10:00WN 2957	3h 30m	97%	88%
American Details →	ONT 06:11 → PHX 07:30AA 1194	1h 09m Phoenix	PHX 08:39 → SLC 11:37AA 6422 · flown by SkyWest	4h 26m	92%	83%
Southwest Details →	ONT 06:12 → OAK 07:38WN 3042	1h 52m Oakland	OAK 09:30 → SLC 12:15WN 4198	5h 03m	100%	83%
Delta Details →	ONT 06:20 → SEA 09:17DL 3816 · flown by SkyWest	1h 48m Seattle	SEA 11:05 → SLC 14:11DL 1265	6h 51m	98%	83%
Tight connection: often missed
United Details →	ONT 13:50 → SFO 15:15UA 1375	56m San Francisco	SFO 16:11 → SLC 19:11UA 543	4h 21m	50%	26%
Southwest Details →	ONT 20:42 → PHX 21:58WN 3160	52m Phoenix	PHX 22:50 → SLC 01:28 +1WN 849	3h 46m	36%	14%
United Details →	ONT 18:39 → SFO 20:07UA 5624 · flown by SkyWest	47m San Francisco	SFO 20:54 → SLC 23:59UA 5753 · flown by SkyWest	4h 20m	10%	7%

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%

DEN · 1h 00m · leaves 05:50 3%

LAS · 1h 00m · leaves 05:30 3%

Afternoon and evening

DFW · 58m · leaves 12:35 25%

PHX · 52m · leaves 20:42 64%

SFO · 47m · leaves 18:39 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.


Southwest WN 383 ONT 06:30 → SJC Delta DL 4026 SJC 09:45 → SLC Connection details →	1h 55m	5h 18m	100%	95%
Southwest WN 864 ONT 05:15 → PHX Delta DL 1447 PHX 09:45 → SLC Connection details →	3h 15m	6h 08m	98%	91%
Southwest WN 3150 ONT 05:30 → LAS Delta DL 1698 LAS 10:00 → SLC Connection details →	3h 25m	5h 57m	100%	89%

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