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

Connect in the morning. The same one-hour layover misses 15% of the time at 9 am and almost half the time at 7 pm.

Nonstops (seasonal or thin)


Delta	ATL	ONT	4h 31m	76%	1.7%	937	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 3 h behind Atlanta). Layovers up to 4 hours. Pick a connection for the details.


Delta Details →	ATL 17:55 → SLC 19:58DL 653	3h 01m Salt Lake City	SLC 22:59 → ONT 23:48DL 1614	8h 53m	98%	87%
Delta Details →	ATL 10:05 → SLC 12:10DL 387	3h 35m Salt Lake City	SLC 15:45 → ONT 16:41DL 4443 · flown by SkyWest	9h 36m	100%	87%
Delta Details →	ATL 09:52 → SEA 12:20DL 774	2h 15m Seattle	SEA 14:35 → ONT 17:19DL 4031 · flown by SkyWest	10h 27m	98%	86%
United Details →	ATL 07:30 → DEN 08:51UA 340	2h 34m Denver	DEN 11:25 → ONT 12:47UA 430	8h 17m	98%	86%
Delta Details →	ATL 14:32 → SEA 16:49DL 481	3h 01m Seattle	SEA 19:50 → ONT 22:41DL 3884 · flown by SkyWest	11h 09m	99%	83%
Delta Details →	ATL 08:15 → SLC 10:15DL 830	1h 04m Salt Lake City	SLC 11:19 → ONT 12:10DL 3172	6h 55m	91%	82%
Southwest Details →	ATL 06:10 → LAS 07:15WN 209	1h 50m Las Vegas	LAS 09:05 → ONT 10:10WN 4179	7h 00m	100%	82%
Frontier Details →	ATL 10:54 → DFW 12:29F9 3021	3h 06m Dallas-Fort Worth	DFW 15:35 → ONT 16:48F9 4689	8h 54m	98%	76%
Tight connection: often missed
American Details →	ATL 08:22 → DFW 09:54AA 1567	46m Dallas-Fort Worth	DFW 10:40 → ONT 11:45AA 2242	6h 23m	68%	49%
Delta Details →	ATL 16:45 → SEA 19:04DL 472	46m Seattle	SEA 19:50 → ONT 22:41DL 3884 · flown by SkyWest	8h 56m	54%	45%
Southwest Details →	ATL 18:20 → DEN 19:40WN 3002	1h 35m Denver	DEN 21:15 → ONT 22:35WN 1663	7h 15m	60%	21%

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 08:15 9%

DFW · 1h 07m · leaves 09:43 13%

SEA · 59m · leaves 07:00 15%

Afternoon and evening

DFW · 1h 01m · leaves 16:16 57%

SFO · 50m · leaves 18:00 64%

LAS · 55m · leaves 20:10 74%

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.


Delta DL 539 ATL 08:30 → PDX Alaska AS 2093 PDX 14:30 → ONT Connection details →	4h 00m	11h 22m	100%	90%
Southwest WN 2114 ATL 06:25 → DEN United UA 430 DEN 11:25 → ONT Connection details →	3h 55m	9h 22m	100%	88%
Alaska AS 348 ATL 08:54 → SEA Delta DL 4031 SEA 14:35 → ONT Connection details →	3h 15m	11h 25m	95%	82%

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