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 90-minute layover misses 1 time in 5 at 6 am and 32% of the time at 9 pm.

Nonstops (seasonal or thin)


United	DEN	SJU	5h 55m	84%	0.3%	333	Flying now

Best connections, any airlines

Most reliable Quickest (80%+ on time)

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


American Details →	DEN 23:45 → MIA 05:41AA 1737	2h 39m Miami	MIA 08:20 → SJU 11:04 +1AA 2582	9h 19m	99%	93%
United Details →	DEN 07:42 → IAH 11:15UA 1720	3h 48m Houston	IAH 15:03 → SJU 20:38UA 701	10h 56m	100%	91%
Southwest Details →	DEN 05:00 → MCO 10:40WN 4854	1h 30m Orlando	MCO 12:10 → SJU 15:05WN 1465	8h 05m	100%	88%
Delta Details →	DEN 00:40 → ATL 05:42DL 302	2h 24m Atlanta	ATL 08:06 → SJU 11:44DL 1757	9h 04m	99%	87%
Southwest Details →	DEN 23:55 → MCO 05:40WN 1597	2h 10m Orlando	MCO 07:50 → SJU 10:45 +1WN 2702	8h 50m	100%	85%
United Details →	DEN 16:20 → IAH 19:57UA 588	3h 59m Houston	IAH 23:56 → SJU 05:29 +1UA 1497	11h 09m	99%	85%
United Details →	DEN 23:59 → IAD 05:27UA 1924	3h 07m Dulles	IAD 08:34 → SJU 12:34 +1UA 2021	10h 35m	100%	83%
United + Southwesttwo ticketsDetails →	DEN 06:00 → MCO 11:44UA 2321	3h 41m Orlando	MCO 15:25 → SJU 18:25WN 2703	10h 25m	100%	83%
Tight connection: often missed
United Details →	DEN 19:35 → IAH 23:06UA 475	50m Houston	IAH 23:56 → SJU 05:29 +1UA 1497	7h 54m	67%	57%
United Details →	DEN 12:40 → EWR 18:35UA 1283	1h 10m Newark	EWR 19:45 → SJU 23:50UA 1543	9h 10m	75%	48%
American Details →	DEN 18:10 → DFW 21:18AA 1322	1h 29m Dallas-Fort Worth	DFW 22:47 → SJU 04:39 +1AA 514	8h 29m	68%	32%

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.

Afternoon and evening

BOS · 1h 01m · leaves 14:45 32%

IAH · 50m · leaves 19:35 33%

MCO · 1h 00m · leaves 14:10 39%

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