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

No clear winner: JetBlue’s BUF → SJU flights land within a few points of 85% on time whatever the hour.

Nonstops (seasonal or thin)


JetBlue	BUF	SJU	4h 36m	85%	1.4%	73	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. Layovers up to 4 hours. Pick a connection for the details.


American Details →	BUF 06:01 → CLT 08:01AA 1204	3h 02m Charlotte	CLT 11:03 → SJU 14:50AA 783	8h 49m	98%	83%
American Details →	BUF 05:20 → PHL 06:46AA 5873 · flown by Piedmont	2h 42m Philadelphia	PHL 09:28 → SJU 13:33AA 903	8h 13m	98%	80%
American + Unitedtwo ticketsDetails →	BUF 10:07 → ORD 11:09AA 4413 · flown by Republic	3h 29m Chicago	ORD 14:38 → SJU 20:34UA 695	10h 27m	99%	78%
Delta Details →	BUF 07:00 → JFK 08:30DL 5284 · flown by Endeavor	4h 00m New York	JFK 12:30 → SJU 16:29DL 1961	9h 29m	98%	78%
JetBlue + Southwesttwo ticketsDetails →	BUF 07:35 → MCO 10:15B6 85	1h 55m Orlando	MCO 12:10 → SJU 15:05WN 1465	7h 30m	90%	78%
Southwest Details →	BUF 12:40 → MCO 15:15WN 762	3h 10m Orlando	MCO 18:25 → SJU 21:30WN 2706	8h 50m	100%	77%
Southwest + JetBluetwo ticketsDetails →	BUF 06:25 → TPA 09:10WN 769	1h 55m Tampa	TPA 11:05 → SJU 14:06B6 1751	7h 39m	100%	72%
Delta Details →	BUF 06:00 → ATL 08:10DL 2664	1h 35m Atlanta	ATL 09:45 → SJU 13:31DL 1882	7h 31m	96%	72%
Tight connection: often missed
JetBlue Details →	BUF 07:35 → MCO 10:15B6 85	47m Orlando	MCO 11:02 → SJU 14:04B6 133	6h 29m	71%	60%
United Details →	BUF 07:00 → ORD 07:59UA 543	50m Chicago	ORD 08:49 → SJU 14:44UA 1996	7h 44m	74%	58%
Southwest Details →	BUF 17:55 → BWI 19:15WN 958	55m Baltimore	BWI 20:10 → SJU 00:40 +1WN 1104	6h 20m	61%	26%

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

JFK · 1h 06m · leaves 10:00 7%

BWI · 50m · leaves 06:05 12%

DTW · 53m · leaves 06:29 14%

Afternoon and evening

IAD · 1h 01m · leaves 15:00 20%

JFK · 1h 00m · leaves 15:50 22%

BWI · 55m · leaves 17:55 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