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 88% on time.

Nonstops (seasonal or thin)


United	SJU	IAH	4h 56m	89%	0.5%	872	Flying now
Spirit	SJU	IAH	5h 17m	68%	1.7%	58	Not flying now

Best connections, one ticket

Most reliable Quickest (80%+ on time)

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


United Details →	SJU 01:00 → EWR 05:10UA 2219	1h 55m Newark	EWR 07:05 → IAH 09:50UA 2438	9h 50m	93%	86%
Delta Details →	SJU 06:00 → ATL 09:50DL 1879	2h 40m Atlanta	ATL 12:30 → IAH 13:38DL 1572	8h 38m	100%	84%
United Details →	SJU 07:20 → IAD 11:21UA 2022	1h 29m Dulles	IAD 12:50 → IAH 15:11UA 1535	8h 51m	99%	82%
United Details →	SJU 07:40 → ORD 11:53UA 2089	47m Chicago	ORD 12:40 → IAH 15:40UA 1448	9h 00m	90%	78%
United Details →	SJU 13:40 → DEN 18:15UA 1368	2h 13m Denver	DEN 20:28 → IAH 23:59UA 2419	11h 19m	98%	78%
United Details →	SJU 16:55 → IAD 20:56UA 2024	1h 24m Dulles	IAD 22:20 → IAH 00:45 +1UA 1986	8h 50m	93%	75%
Delta Details →	SJU 14:14 → DTW 18:53DL 1913	1h 32m Detroit	DTW 20:25 → IAH 22:24DL 1633	9h 10m	95%	74%
American Details →	SJU 07:00 → PHL 11:04AA 3063	1h 58m Philadelphia	PHL 13:02 → IAH 15:47AA 1925	9h 47m	97%	73%
Tight connection: often missed
Frontier Details →	SJU 03:10 → MCO 06:10F9 1823	50m Orlando	MCO 07:00 → IAH 08:47F9 1417	6h 37m	73%	62%

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

ATL · 1h 10m · leaves 07:30 3%

ORD · 47m · leaves 07:40 10%

CLT · 1h 15m · leaves 07:25 11%

Afternoon and evening

CLT · 1h 06m · leaves 15:40 12%

PHL · 1h 17m · leaves 14:25 15%

ATL · 50m · leaves 17:56 18%

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.


Southwest WN 3721 SJU 05:00 → MCO United UA 1493 MCO 11:57 → IAH Connection details →	3h 57m	9h 29m	100%	95%
JetBlue B6 452 SJU 06:00 → TPA United UA 2421 TPA 11:55 → IAH Connection details →	2h 56m	8h 22m	100%	88%
American AA 2592 SJU 00:59 → ORD United UA 1231 ORD 07:35 → IAH Connection details →	2h 31m	10h 37m	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