Itineraries flown on 20+ days in the Jun 6 – Jul 31, 2026 schedule · each leg’s record Aug 2025 – Jul 2026

No clear winner: airlines and hours on this route all land within a few points of 72% on time.

Nonstops


United	ORD	BUF	1h 46m	73%	2.8%	1,316	Flying now
American	ORD	BUF	1h 43m	71%	3.3%	1,229	Flying now

Best connections, one ticket

Most reliable Quickest (80%+ on time)

Ranked by chance you reach Buffalo on time. Total trip = scheduled departure to arrival, layover included (Buffalo is 1 h ahead of Chicago). Layovers up to 4 hours. Pick a connection for the details.


American Details →	ORD 08:30 → BOS 12:07AA 4106 · flown by Envoy	1h 48m Boston	BOS 13:55 → BUF 15:44AA 4440 · flown by Republic	6h 14m	99%	87%
American Details →	ORD 05:07 → CLT 08:10AA 2842	3h 00m Charlotte	CLT 11:10 → BUF 12:54AA 1616	6h 48m	98%	85%
United Details →	ORD 06:30 → IAD 09:24UA 1689	3h 35m Dulles	IAD 12:59 → BUF 14:25UA 4335 · flown by CommuteAir	6h 55m	100%	79%
Delta Details →	ORD 08:05 → ATL 11:08DL 2426	2h 52m Atlanta	ATL 14:00 → BUF 16:06DL 2266	7h 01m	98%	76%
United Details →	ORD 10:51 → EWR 14:17UA 1856	2h 20m Newark	EWR 16:37 → BUF 18:05UA 3607 · flown by Republic	6h 14m	98%	75%
American Details →	ORD 15:19 → PHL 18:29AA 2925	3h 51m Philadelphia	PHL 22:20 → BUF 23:53AA 5911 · flown by Piedmont	7h 34m	97%	74%
Delta Details →	ORD 15:22 → ATL 18:36DL 1477	3h 13m Atlanta	ATL 21:49 → BUF 23:59DL 2334	7h 37m	98%	72%
United Details →	ORD 11:07 → IAD 14:12UA 1869	3h 18m Dulles	IAD 17:30 → BUF 19:03UA 4823 · flown by CommuteAir	6h 56m	99%	72%
Tight connection: often missed
Delta Details →	ORD 13:00 → JFK 16:37DL 5035 · flown by Endeavor	52m New York	JFK 17:29 → BUF 19:25DL 5250 · flown by Endeavor	5h 26m	67%	40%
American Details →	ORD 14:59 → DFW 17:36AA 2257	1h 09m Dallas-Fort Worth	DFW 18:45 → BUF 22:50AA 574	6h 51m	69%	38%
American Details →	ORD 13:32 → PHL 16:49AA 1859	51m Philadelphia	PHL 17:40 → BUF 19:12AA 6114 · flown by Piedmont	4h 40m	62%	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.

Morning

IAD · 1h 07m · leaves 08:40 6%

PHL · 1h 09m · leaves 08:29 17%

DFW · 51m · leaves 08:30 37%

Afternoon and evening

LGA · 59m · leaves 17:35 50%

EWR · 52m · leaves 16:31 51%

JFK · 1h 00m · leaves 18:00 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.


United UA 1076 ORD 07:33 → BOS American AA 4440 BOS 13:55 → BUF Connection details →	2h 50m	7h 11m	99%	87%
American AA 3022 ORD 06:00 → BOS JetBlue B6 1215 BOS 11:05 → BUF Connection details →	1h 31m	5h 36m	91%	83%
United UA 215 ORD 10:25 → MSP Delta DL 1749 MSP 15:22 → BUF Connection details →	3h 10m	7h 02m	100%	81%

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