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

The best bet has a stop: Southwest via Phoenix (6h 10m) reaches Ontario on time 86% of the time, against 70% on the nonstop.

Nonstops (seasonal or thin)


Southwest	MDW	ONT	4h 15m	71%	1.1%	360	Flying now

Best connections, any airlines

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.


Southwest + Frontiertwo ticketsDetails →	MDW 05:15 → DEN 06:50WN 2989	1h 54m Denver	DEN 08:44 → ONT 10:05F9 2907	6h 50m	100%	90%
Southwest + Unitedtwo ticketsDetails →	MDW 06:50 → DEN 08:20WN 2765	3h 05m Denver	DEN 11:25 → ONT 12:47UA 430	7h 57m	100%	88%
Southwest Details →	MDW 05:20 → PHX 06:55WN 2858	3h 10m Phoenix	PHX 10:05 → ONT 11:20WN 431	8h 00m	100%	88%
Southwest + Alaskatwo ticketsDetails →	MDW 10:05 → PDX 12:25WN 2809	2h 05m Portland	PDX 14:30 → ONT 16:52AS 2093 · flown by Horizon	8h 47m	96%	88%
Southwest + Deltatwo ticketsDetails →	MDW 10:02 → SLC 12:28WN 2951	3h 17m Salt Lake City	SLC 15:45 → ONT 16:41DL 4443 · flown by SkyWest	8h 39m	100%	87%
Southwest Details →	MDW 07:30 → LAS 09:20WN 347	2h 10m Las Vegas	LAS 11:30 → ONT 12:32WN 2298	7h 02m	100%	82%
Southwest + Frontiertwo ticketsDetails →	MDW 18:00 → DEN 19:45WN 1497	2h 44m Denver	DEN 22:29 → ONT 23:49F9 1261	7h 49m	91%	74%
Southwest + Frontiertwo ticketsDetails →	MDW 10:10 → LAS 12:00WN 2794	1h 59m Las Vegas	LAS 13:59 → ONT 15:09F9 1357	6h 59m	87%	72%
Tight connection: often missed
Southwest Details →	MDW 11:20 → PHX 12:55WN 4189	1h 00m Phoenix	PHX 13:55 → ONT 15:05WN 670	5h 45m	66%	46%
Southwest Details →	MDW 11:20 → BNA 12:45WN 2733	1h 10m Nashville	BNA 13:55 → ONT 16:00WN 855	6h 40m	69%	36%

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 00m · leaves 05:15 2%

Afternoon and evening

ATL · 1h 10m · leaves 12:50 12%

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.

The table above includes two-ticket connections (marked “two tickets”), held to the 90-minute minimum. One ticket only →

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