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 75-minute layover misses 5% of the time at 10 am and 1 time in 3 at 7 pm.

Nonstops


United	IAD	SFO	5h 51m	79%	0.8%	2,691	Flying now
Alaska	IAD	SFO	5h 47m	76%few flights	0.0%	38	Not flying now

Best connections, one ticket

Most reliable Quickest (80%+ on time)

Ranked by chance you reach San Francisco on time. Total trip = scheduled departure to arrival, layover included (San Francisco is 3 h behind Dulles). Layovers up to 4 hours. Pick a connection for the details.


United Details →	IAD 13:10 → LAX 15:42UA 1689	1h 28m Los Angeles	LAX 17:10 → SFO 18:38UA 233	8h 28m	98%	81%
United Details →	IAD 08:35 → BOS 10:20UA 641	1h 15m Boston	BOS 11:35 → SFO 15:02UA 1074	9h 27m	95%	75%
United Details →	IAD 08:15 → DEN 10:10UA 792	3h 15m Denver	DEN 13:25 → SFO 15:09UA 1812	9h 54m	97%	74%
United Details →	IAD 08:26 → SAN 10:49UA 1930	2h 50m San Diego	SAN 13:39 → SFO 15:19UA 1763	9h 53m	100%	73%
United Details →	IAD 06:30 → IAH 08:39UA 1935	56m Houston	IAH 09:35 → SFO 11:35UA 2358	8h 05m	100%	73%
United Details →	IAD 10:31 → ORD 11:53UA 1252	2h 37m Chicago	ORD 14:30 → SFO 17:19UA 1577	9h 48m	100%	72%
United Details →	IAD 10:13 → DEN 12:05UA 1865	3h 42m Denver	DEN 15:47 → SFO 17:30UA 2633	10h 17m	99%	72%
United Details →	IAD 06:30 → DEN 08:22UA 2031	2h 59m Denver	DEN 11:21 → SFO 13:04UA 1561	9h 34m	100%	72%
Tight connection: often missed
United Details →	IAD 08:15 → ORD 09:36UA 1775	49m Chicago	ORD 10:25 → SFO 13:14UA 543	7h 59m	69%	43%
United Details →	IAD 17:42 → ORD 18:50UA 2497	1h 14m Chicago	ORD 20:04 → SFO 22:57UA 1495	8h 15m	67%	30%
United Details →	IAD 17:15 → MCI 19:03UA 2057	56m Kansas City	MCI 19:59 → SFO 21:50UA 1429	7h 35m	72%	17%

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

BOS · 1h 15m · leaves 08:35 5%

SAN · 1h 06m · leaves 08:26 6%

SLC · 1h 08m · leaves 07:15 10%

Afternoon and evening

ATL · 48m · leaves 17:51 33%

IAH · 54m · leaves 14:53 37%

DFW · 1h 09m · leaves 19:31 45%

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.


United UA 1930 IAD 08:26 → SAN Alaska AS 3352 SAN 13:30 → SFO Connection details →	2h 41m	9h 48m	98%	71%
United UA 2739 IAD 08:15 → ATL Delta DL 750 ATL 12:56 → SFO Connection details →	2h 42m	9h 39m	97%	70%
United UA 3552 IAD 10:00 → BOS JetBlue B6 233 BOS 15:50 → SFO Connection details →	3h 58m	12h 24m	100%	69%

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