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 80-minute layover misses 5% of the time at 8 am and 31% of the time at 8 pm.

Nonstops


United	DEN	SDF	2h 41m	83%	0.5%	730	Flying now
Southwest	DEN	SDF	2h 25m	71%	1.1%	366	Flying now

Best connections, one ticket

Most reliable Quickest (80%+ on time)

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


Southwest Details →	DEN 23:55 → MCO 05:40WN 1597	2h 20m Orlando	MCO 08:00 → SDF 10:10 +1WN 872	8h 15m	100%	90%
United Details →	DEN 23:59 → IAD 05:27UA 1924	3h 04m Dulles	IAD 08:31 → SDF 10:23 +1UA 3526 · flown by Republic	8h 24m	100%	88%
American Details →	DEN 05:00 → DFW 08:05AA 2612	1h 26m Dallas-Fort Worth	DFW 09:31 → SDF 12:48AA 3791 · flown by Envoy	5h 48m	95%	88%
Delta Details →	DEN 00:40 → ATL 05:42DL 302	3h 28m Atlanta	ATL 09:10 → SDF 10:29DL 1374	7h 52m	100%	87%
Southwest Details →	DEN 07:10 → MDW 10:30WN 114	2h 15m Chicago	MDW 12:45 → SDF 14:55WN 4473	5h 45m	100%	85%
Delta Details →	DEN 09:40 → ATL 14:35DL 2235	3h 24m Atlanta	ATL 17:59 → SDF 19:24DL 2831	7h 44m	100%	83%
Delta Details →	DEN 14:15 → ATL 19:20DL 706	3h 42m Atlanta	ATL 23:02 → SDF 00:26 +1DL 2624	8h 13m	99%	82%
United Details →	DEN 10:07 → IAH 13:40UA 1129	2h 55m Houston	IAH 16:35 → SDF 20:01UA 4050 · flown by Mesa	7h 54m	100%	82%
Tight connection: often missed
American Details →	DEN 15:57 → CLT 21:27AA 1735	1h 35m Charlotte	CLT 23:02 → SDF 00:31 +1AA 671	6h 35m	74%	52%
American Details →	DEN 14:22 → ORD 18:16AA 1760	1h 13m Chicago	ORD 19:29 → SDF 22:04AA 4603 · flown by Republic	5h 42m	67%	46%
United Details →	DEN 16:29 → ORD 20:14UA 675	1h 11m Chicago	ORD 21:25 → SDF 23:59UA 3659 · flown by Republic	5h 30m	69%	45%

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

DTW · 1h 16m · leaves 06:05 5%

IAD · 1h 07m · leaves 06:13 6%

ORD · 1h 18m · leaves 06:00 6%

Afternoon and evening

ATL · 1h 08m · leaves 16:43 15%

ORD · 1h 13m · leaves 14:22 33%

EWR · 50m · leaves 13:41 40%

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.


Frontier F9 2550 DEN 05:05 → DFW American AA 3758 DFW 12:07 → SDF Connection details →	3h 58m	8h 17m	97%	83%
Southwest WN 2258 DEN 10:15 → ATL Delta DL 2831 ATL 17:59 → SDF Connection details →	2h 39m	7h 09m	96%	81%
Frontier F9 2141 DEN 09:15 → PHX Southwest WN 3329 PHX 13:05 → SDF Connection details →	2h 54m	8h 15m	98%	80%

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