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

The nonstop is quickest: United ORD → ONT (4h 31m), on time 3 times in 5. United via Denver (7h 42m) is more reliable, 87%, but takes 3h 11m longer.

Nonstops (seasonal or thin)


United	ORD	ONT	4h 31m	62%	1.4%	290	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 (Ontario is 2 h behind Chicago). Layovers up to 4 hours. Pick a connection for the details.


United Details →	ORD 06:00 → DEN 07:42UA 2806	3h 43m Denver	DEN 11:25 → ONT 12:47UA 430	8h 47m	100%	87%
United Details →	ORD 14:30 → SFO 17:19UA 1577	3h 41m San Francisco	SFO 21:00 → ONT 22:37UA 552	10h 07m	96%	78%
United Details →	ORD 14:15 → IAH 17:20UA 2451	3h 11m Houston	IAH 20:31 → ONT 21:55UA 1563	9h 40m	97%	77%
United Details →	ORD 06:10 → SFO 08:47UA 246	1h 53m San Francisco	SFO 10:40 → ONT 12:12UA 2661	8h 02m	99%	76%
Delta Details →	ORD 07:45 → SLC 10:15DL 2231	1h 04m Salt Lake City	SLC 11:19 → ONT 12:10DL 3172	6h 25m	83%	75%
Frontier Details →	ORD 09:28 → DFW 11:57F9 1341	3h 38m Dallas-Fort Worth	DFW 15:35 → ONT 16:48F9 4689	9h 20m	98%	73%
American Details →	ORD 05:00 → DFW 07:30AA 760	3h 10m Dallas-Fort Worth	DFW 10:40 → ONT 11:45AA 2242	8h 45m	99%	72%
Alaska Details →	ORD 06:00 → SEA 08:38AS 715	1h 47m Seattle	SEA 10:25 → ONT 13:09AS 565	9h 09m	95%	70%
Tight connection: often missed
American Details →	ORD 17:34 → PHX 19:19AA 3261	1h 11m Phoenix	PHX 20:30 → ONT 21:44AA 1238	6h 10m	62%	44%
American Details →	ORD 14:59 → DFW 17:36AA 2257	1h 14m Dallas-Fort Worth	DFW 18:50 → ONT 19:59AA 2236	7h 00m	69%	40%
American Details →	ORD 19:26 → DFW 22:08AA 3544 · flown by Envoy	47m Dallas-Fort Worth	DFW 22:55 → ONT 23:59 +1AA 1534	6h 36m	64%	23%

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

SLC · 1h 04m · leaves 07:45 17%

DFW · 50m · leaves 05:00 19%

Afternoon and evening

DFW · 47m · leaves 19:26 36%

PHX · 55m · leaves 14:25 70%

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 2284 ORD 08:00 → PDX Alaska AS 2093 PDX 14:30 → ONT Connection details →	3h 58m	10h 52m	99%	90%
United UA 2666 ORD 05:00 → DEN Frontier F9 2907 DEN 08:44 → ONT Connection details →	2h 02m	7h 05m	99%	90%
American AA 1747 ORD 06:41 → DEN United UA 430 DEN 11:25 → ONT Connection details →	3h 01m	8h 06m	97%	86%

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