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 70-minute layover misses 5% of the time at 12 pm and 38% of the time at 7 pm.

Nonstops


United	IAD	DEN	4h 04m	85%	0.5%	2,787	Flying now
Southwest	IAD	DEN	3h 55m	79%	0.9%	678	Not flying now

Best connections, one ticket

Most reliable Quickest (80%+ on time)

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


United Details →	IAD 06:10 → ORD 07:27UA 2070	3h 27m Chicago	ORD 10:54 → DEN 12:45UA 581	8h 35m	100%	97%
United Details →	IAD 08:30 → AUS 10:56UA 637	1h 59m Austin	AUS 12:55 → DEN 14:14UA 1541	7h 44m	99%	94%
United Details →	IAD 13:10 → LAX 15:42UA 1689	3h 03m Los Angeles	LAX 18:45 → DEN 22:15UA 2610	11h 05m	99%	90%
United Details →	IAD 15:15 → LAX 17:47UA 684	1h 58m Los Angeles	LAX 19:45 → DEN 23:15UA 2829	10h 00m	98%	90%
United Details →	IAD 07:00 → LAX 09:26UA 325	1h 29m Los Angeles	LAX 10:55 → DEN 14:27UA 2061	9h 27m	99%	89%
United Details →	IAD 08:45 → MCO 11:08UA 379	1h 42m Orlando	MCO 12:50 → DEN 14:51UA 1520	8h 06m	97%	89%
United Details →	IAD 08:45 → MSP 10:28UA 1998	1h 06m Minneapolis	MSP 11:34 → DEN 12:45UA 2232	6h 00m	93%	88%
United Details →	IAD 08:20 → CLE 09:41UA 1926	1h 29m Cleveland	CLE 11:10 → DEN 12:26UA 2246	6h 06m	100%	87%
Tight connection: often missed
United Details →	IAD 12:48 → SDF 14:37UA 3980 · flown by Mesa	48m Louisville	SDF 15:25 → DEN 16:24UA 1510	5h 36m	68%	53%
United Details →	IAD 17:42 → ORD 18:50UA 2497	1h 10m Chicago	ORD 20:00 → DEN 22:01UA 767	6h 19m	62%	43%
United Details →	IAD 12:40 → LGA 14:10UA 3698 · flown by Republic	1h 10m New York	LGA 15:20 → DEN 17:56UA 1729	7h 16m	72%	42%

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

TPA · 1h 13m · leaves 09:00 5%

ORD · 1h 18m · leaves 08:15 6%

MSP · 1h 06m · leaves 08:45 7%

Afternoon and evening

ATL · 1h 00m · leaves 17:51 26%

ORD · 1h 10m · leaves 17:42 38%

DFW · 55m · leaves 19:31 51%

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 3996 IAD 06:00 → MSP United UA 2232 MSP 11:34 → DEN Connection details →	3h 39m	8h 45m	96%	88%
Delta DL 432 IAD 07:15 → SLC United UA 4720 SLC 13:05 → DEN Connection details →	3h 13m	9h 36m	96%	86%
Delta DL 2127 IAD 06:00 → ATL United UA 1327 ATL 11:10 → DEN Connection details →	3h 24m	8h 28m	97%	86%

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