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

No clear winner: Southwest’s MDW → SAN flights land within a few points of 73% on time whatever the hour.

Nonstops


Southwest	MDW	SAN	4h 20m	73%	1.4%	1,092	Flying now

Best connections, one ticket

Most reliable Quickest (80%+ on time)

Ranked by chance you reach San Diego on time. Total trip = scheduled departure to arrival, layover included (San Diego is 2 h behind Chicago). Layovers up to 4 hours. Pick a connection for the details.


Southwest Details →	MDW 05:15 → DEN 06:50WN 2989	1h 25m Denver	DEN 08:15 → SAN 09:40WN 1699	6h 25m	100%	86%
Southwest Details →	MDW 10:15 → MKE 11:00WN 1702	3h 30m Milwaukee	MKE 14:30 → SAN 16:40WN 2956	8h 25m	98%	84%
Delta Details →	MDW 06:00 → ATL 08:55DL 1285	2h 58m Atlanta	ATL 11:53 → SAN 13:21DL 540	9h 21m	96%	80%
Southwest Details →	MDW 06:50 → DEN 08:20WN 2765	2h 12m Denver	DEN 10:32 → SAN 12:00WN 1700	7h 07m	100%	79%
Delta Details →	MDW 11:05 → ATL 14:01DL 1063	1h 35m Atlanta	ATL 15:36 → SAN 17:00DL 843	7h 56m	95%	76%
Southwest Details →	MDW 05:20 → PHX 06:55WN 2858	2h 20m Phoenix	PHX 09:15 → SAN 10:35WN 1677	7h 13m	100%	71%
Delta Details →	MDW 13:49 → MSP 15:33DL 4820 · flown by Endeavor	3h 17m Minneapolis	MSP 18:50 → SAN 20:36DL 2145	8h 51m	94%	66%
Southwest Details →	MDW 08:40 → PHX 10:20WN 3016	3h 15m Phoenix	PHX 13:35 → SAN 14:45WN 897	8h 05m	100%	64%
Tight connection: often missed
Delta Details →	MDW 13:26 → DTW 15:44DL 4688 · flown by Endeavor	51m Detroit	DTW 16:35 → SAN 18:21DL 369	6h 55m	75%	54%
Southwest Details →	MDW 11:20 → BNA 12:45WN 2733	55m Nashville	BNA 13:40 → SAN 15:45WN 4111	6h 25m	48%	17%
Southwest Details →	MDW 16:15 → DEN 18:00WN 2769	1h 15m Denver	DEN 19:15 → SAN 20:40WN 1703	6h 25m	73%	14%

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

ATL · 1h 13m · leaves 06:00 9%

DTW · 55m · leaves 09:17 16%

Afternoon and evening

DEN · 1h 15m · leaves 16:15 27%

MSP · 56m · leaves 19:06 41%

TPA · 55m · leaves 14:25 52%

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 2765 MDW 06:50 → DEN United UA 1940 DEN 11:15 → SAN Connection details →	2h 55m	7h 51m	100%	82%
Southwest WN 3054 MDW 07:15 → ATL Delta DL 540 ATL 11:53 → SAN Connection details →	1h 48m	8h 06m	96%	82%
Southwest WN 4154 MDW 08:55 → ATL Delta DL 843 ATL 15:36 → SAN Connection details →	3h 51m	10h 06m	100%	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