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

No clear winner: United’s IAH → GSP flights land within a few points of 83% on time whatever the hour.

Nonstops (seasonal or thin)


United	IAH	GSP	2h 20m	83%	0.9%	671	Flying now

Best connections, any airlines

Most reliable Quickest (80%+ on time)

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


Delta Details →	IAH 05:40 → ATL 08:43DL 1069	1h 14m Atlanta	ATL 09:57 → GSP 10:57DL 2158	4h 17m	97%	89%
American Details →	IAH 06:01 → CLT 09:43AA 2011	1h 24m Charlotte	CLT 11:07 → GSP 12:14AA 5802 · flown by Piedmont	5h 13m	94%	86%
United + Deltatwo ticketsDetails →	IAH 07:20 → ATL 10:39UA 1030	2h 33m Atlanta	ATL 13:12 → GSP 14:13DL 1273	5h 53m	98%	85%
United Details →	IAH 06:30 → DEN 08:02UA 2643	2h 11m Denver	DEN 10:13 → GSP 15:19UA 1786	7h 49m	100%	81%
Delta Details →	IAH 07:02 → ATL 10:05DL 1315	1h 10m Atlanta	ATL 11:15 → GSP 12:18DL 1725	4h 16m	91%	81%
United + Americantwo ticketsDetails →	IAH 07:25 → CLT 11:02UA 3988 · flown by Mesa	2h 03m Charlotte	CLT 13:05 → GSP 14:07AA 5805 · flown by Piedmont	5h 42m	94%	80%
Delta Details →	IAH 08:05 → ATL 11:09DL 644	3h 58m Atlanta	ATL 15:07 → GSP 16:10DL 3095	7h 05m	100%	77%
United Details →	IAH 07:20 → IAD 11:28UA 1549	1h 12m Dulles	IAD 12:40 → GSP 14:20UA 4962 · flown by CommuteAir	6h 00m	96%	77%
Tight connection: often missed
United Details →	IAH 12:13 → IAD 16:30UA 2366	50m Dulles	IAD 17:20 → GSP 19:04UA 4963 · flown by CommuteAir	5h 51m	64%	50%
American Details →	IAH 11:26 → ORD 14:17AA 1909	53m Chicago	ORD 15:10 → GSP 18:11AA 3559 · flown by Envoy	5h 46m	56%	43%
American Details →	IAH 12:21 → PHL 16:49AA 1927	59m Philadelphia	PHL 17:48 → GSP 19:49AA 5618 · flown by PSA	6h 28m	54%	34%

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 14m · leaves 05:40 3%

IAD · 1h 12m · leaves 07:20 4%

LGA · 1h 07m · leaves 07:00 10%

Afternoon and evening

ATL · 1h 01m · leaves 16:51 41%

DTW · 50m · leaves 15:27 44%

PHL · 59m · leaves 12:21 46%

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