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 one-hour layover misses 8% of the time at 8 am and barely half the time at 9 pm.

Nonstops


United	BOS	SFO	6h 34m	76%	1.3%	1,905	Flying now
Delta	BOS	SFO	6h 47m	72%	1.5%	918	Flying now
JetBlue	BOS	SFO	6h 36m	70%	1.8%	1,738	Flying now
Alaska	BOS	SFO	6h 40m	61%	0.6%	173	Not flying now
Southwest	BOS	SFO	–	100%few flights	0.0%	1	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 Boston). Layovers up to 4 hours. Pick a connection for the details.


United Details →	BOS 05:45 → IAD 07:23UA 1734	1h 12m Dulles	IAD 08:35 → SFO 11:19UA 1147	8h 34m	98%	81%
JetBlue Details →	BOS 05:15 → JFK 06:28B6 917	1h 32m New York	JFK 08:00 → SFO 11:20B6 15	9h 05m	99%	80%
United Details →	BOS 09:25 → IAD 11:07UA 2098	3h 44m Dulles	IAD 14:51 → SFO 17:38UA 2862	11h 13m	99%	80%
United Details →	BOS 07:45 → DEN 10:19UA 647	3h 06m Denver	DEN 13:25 → SFO 15:09UA 1812	10h 24m	100%	74%
United Details →	BOS 15:54 → IAH 19:08UA 1183	2h 51m Houston	IAH 21:59 → SFO 00:05 +1UA 1609	11h 11m	95%	74%
American Details →	BOS 06:00 → PHL 07:37AA 1146	50m Philadelphia	PHL 08:27 → SFO 11:29AA 1524	8h 28m	92%	73%
United Details →	BOS 09:40 → DEN 12:12UA 662	3h 35m Denver	DEN 15:47 → SFO 17:30UA 2633	10h 50m	99%	72%
United Details →	BOS 09:50 → ORD 11:43UA 1349	2h 47m Chicago	ORD 14:30 → SFO 17:19UA 1577	10h 29m	98%	70%
Tight connection: often missed
Delta Details →	BOS 11:15 → SLC 14:24DL 464	46m Salt Lake City	SLC 15:10 → SFO 16:12DL 1088	8h 00m	58%	38%
United Details →	BOS 17:00 → ORD 19:00UA 2040	1h 04m Chicago	ORD 20:04 → SFO 22:57UA 1495	8h 57m	60%	26%
American Details →	BOS 17:38 → ORD 19:59AA 1592	1h 01m Chicago	ORD 21:00 → SFO 23:58AA 3054	9h 04m	38%	11%

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

IAD · 1h 12m · leaves 05:45 2%

MSP · 1h 20m · leaves 05:55 3%

LAX · 1h 20m · leaves 06:21 3%

Afternoon and evening

CLT · 49m · leaves 16:47 39%

PHL · 57m · leaves 17:05 42%

ORD · 1h 01m · leaves 17:38 62%

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 2004 BOS 10:55 → LAX United UA 233 LAX 17:10 → SFO Connection details →	3h 03m	10h 43m	98%	80%
JetBlue B6 917 BOS 05:15 → JFK Alaska AS 227 JFK 09:30 → SFO Connection details →	3h 02m	10h 37m	100%	78%
American AA 4401 BOS 06:01 → JFK JetBlue B6 215 JFK 10:30 → SFO Connection details →	3h 00m	11h 07m	99%	76%

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