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 (7h 20m) reaches Ontario on time 84% of the time, against 64% on the nonstop.

Nonstops (seasonal or thin)


Southwest	BWI	ONT	5h 30m	64%	0.4%	281	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 Baltimore). Layovers up to 4 hours. Pick a connection for the details.


Southwest Details →	BWI 07:00 → PHX 08:50WN 1049	1h 15m Phoenix	PHX 10:05 → ONT 11:20WN 431	7h 20m	95%	84%
Delta Details →	BWI 07:10 → SLC 09:49DL 1176	1h 30m Salt Lake City	SLC 11:19 → ONT 12:10DL 3172	8h 00m	93%	84%
Southwest Details →	BWI 06:25 → LAS 08:25WN 973	3h 05m Las Vegas	LAS 11:30 → ONT 12:32WN 2298	9h 07m	100%	82%
United Details →	BWI 08:30 → DEN 10:25UA 2412	1h 00m Denver	DEN 11:25 → ONT 12:47UA 430	7h 17m	90%	80%
Delta Details →	BWI 05:40 → ATL 07:31DL 2950	1h 44m Atlanta	ATL 09:15 → ONT 10:40DL 665	8h 00m	97%	78%
United Details →	BWI 15:03 → IAH 17:19UA 2095	3h 12m Houston	IAH 20:31 → ONT 21:55UA 1563	9h 52m	97%	77%
Alaska Details →	BWI 16:19 → PDX 18:56AS 1369	2h 34m Portland	PDX 21:30 → ONT 23:51AS 97	10h 32m	94%	77%
United Details →	BWI 06:38 → SFO 09:28UA 2192	1h 12m San Francisco	SFO 10:40 → ONT 12:12UA 2661	8h 34m	97%	76%
Tight connection: often missed
Southwest Details →	BWI 15:48 → LAS 17:48WN 1102	1h 22m Las Vegas	LAS 19:10 → ONT 20:10WN 208	7h 22m	75%	40%
American Details →	BWI 19:17 → DFW 21:42AA 1626	1h 13m Dallas-Fort Worth	DFW 22:55 → ONT 23:59 +1AA 1534	7h 45m	73%	26%

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

SFO · 1h 12m · leaves 06:38 3%

PHX · 1h 15m · leaves 07:00 5%

DEN · 1h 00m · leaves 08:30 10%

Afternoon and evening

DEN · 1h 02m · leaves 16:23 20%

SJC · 1h 15m · leaves 12:50 24%

DFW · 1h 13m · leaves 19:17 27%

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 4436 BWI 06:05 → DEN United UA 430 DEN 11:25 → ONT Connection details →	3h 35m	9h 42m	100%	88%
Southwest WN 974 BWI 09:35 → LAS Frontier F9 1357 LAS 13:59 → ONT Connection details →	2h 24m	8h 34m	94%	77%
Southwest WN 1101 BWI 14:50 → SFO United UA 552 SFO 21:00 → ONT Connection details →	3h 30m	10h 47m	92%	76%

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