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

No nonstop, and no clear pattern: the best connection reaches Dulles on time 84% of the time.

Best connections, any airlines

Ranked by chance you reach Dulles on time. Total trip = scheduled departure to arrival, layover included (Dulles is 3 h ahead of Ontario). Layovers up to 4 hours. Pick a connection for the details.


Delta + Unitedtwo ticketsDetails →	ONT 06:20 → SEA 09:17DL 3816 · flown by SkyWest	3h 43m Seattle	SEA 13:00 → IAD 21:06UA 2131	11h 46m	99%	92%
Delta + Unitedtwo ticketsDetails →	ONT 17:21 → SLC 20:17DL 4443 · flown by SkyWest	3h 42m Salt Lake City	SLC 23:59 → IAD 06:13 +1UA 726	9h 52m	96%	89%
Southwest + Unitedtwo ticketsDetails →	ONT 05:15 → PHX 06:30WN 864	2h 20m Phoenix	PHX 08:50 → IAD 16:17UA 1873	8h 02m	98%	89%
Alaska + Unitedtwo ticketsDetails →	ONT 17:32 → PDX 19:49AS 2456 · flown by Horizon	3h 41m Portland	PDX 23:30 → IAD 07:32 +1UA 498	11h 00m	99%	87%
Southwest + Unitedtwo ticketsDetails →	ONT 05:30 → LAS 06:35WN 3150	2h 13m Las Vegas	LAS 08:48 → IAD 16:24UA 1140	7h 54m	99%	87%
Delta + Unitedtwo ticketsDetails →	ONT 17:59 → SEA 20:50DL 4031 · flown by SkyWest	2h 30m Seattle	SEA 23:20 → IAD 07:22 +1UA 264	10h 23m	98%	84%
Southwest + Unitedtwo ticketsDetails →	ONT 08:05 → DEN 11:15WN 3145	2h 38m Denver	DEN 13:53 → IAD 19:22UA 347	8h 17m	96%	84%
Delta Details →	ONT 22:00 → ATL 05:18DL 2892	2h 25m Atlanta	ATL 07:43 → IAD 09:26 +1DL 1324	8h 28m	100%	84%
Tight connection: often missed
United Details →	ONT 13:50 → SFO 15:15UA 1375	1h 19m San Francisco	SFO 16:34 → IAD 00:55 +1UA 1453	8h 05m	72%	62%
American Details →	ONT 12:35 → DFW 17:50AA 2242	54m Dallas-Fort Worth	DFW 18:44 → IAD 22:46AA 1132	7h 17m	74%	33%
United Details →	ONT 18:39 → SFO 20:07UA 5624 · flown by SkyWest	1h 23m San Francisco	SFO 21:30 → IAD 05:53 +1UA 357	8h 14m	43%	31%

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

IAH · 1h 09m · leaves 05:45 6%

Afternoon and evening

DFW · 54m · leaves 12:35 26%

SFO · 1h 19m · leaves 13:50 28%

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