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 4 in 5 on time.

Nonstops


Alaska	SEA	MIA	5h 59m	81%	0.5%	391	Flying now
Delta	SEA	MIA	6h 06m	80%	1.4%	365	Flying now
American	SEA	MIA	5h 52m	77%	0.9%	454	Flying now

Best connections, one ticket

Most reliable Quickest (80%+ on time)

Ranked by chance you reach Miami on time. Total trip = scheduled departure to arrival, layover included (Miami is 3 h ahead of Seattle). Layovers up to 4 hours. Pick a connection for the details.


Delta Details →	SEA 23:59 → MSP 05:17DL 953	3h 38m Minneapolis	MSP 08:55 → MIA 13:37 +1DL 2129	10h 38m	100%	85%
American Details →	SEA 21:35 → CLT 05:41AA 2793	3h 44m Charlotte	CLT 09:25 → MIA 11:37 +1AA 1436	11h 02m	100%	85%
Delta Details →	SEA 21:45 → ATL 05:36DL 567	1h 54m Atlanta	ATL 07:30 → MIA 09:30 +1DL 2836	8h 48m	98%	85%
Delta Details →	SEA 17:59 → SLC 21:09DL 1165	1h 51m Salt Lake City	SLC 23:00 → MIA 05:42 +1DL 2040	8h 43m	94%	84%
Delta Details →	SEA 23:10 → DTW 06:27DL 810	2h 55m Detroit	DTW 09:22 → MIA 12:30 +1DL 1468	10h 20m	99%	83%
Delta Details →	SEA 22:58 → ATL 06:45DL 409	2h 10m Atlanta	ATL 08:55 → MIA 10:57 +1DL 1510	8h 58m	100%	82%
American Details →	SEA 22:35 → PHL 06:48AA 2522	1h 27m Philadelphia	PHL 08:15 → MIA 11:12 +1AA 2184	9h 37m	94%	81%
Delta Details →	SEA 23:59 → ATL 07:46DL 652	3h 14m Atlanta	ATL 11:00 → MIA 13:04 +1DL 1332	10h 05m	99%	80%
Tight connection: often missed
United Details →	SEA 10:52 → ORD 17:05UA 2835	1h 00m Chicago	ORD 18:05 → MIA 22:27UA 2180	8h 35m	72%	50%
American Details →	SEA 12:44 → PHL 21:06AA 2534	49m Philadelphia	PHL 21:55 → MIA 00:52 +1AA 2936	9h 08m	71%	39%
Delta Details →	SEA 08:40 → ATL 16:33DL 797	1h 12m Atlanta	ATL 17:45 → MIA 19:56DL 1631	8h 16m	75%	36%

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

ORD · 57m · leaves 23:56 7%

ATL · 1h 09m · leaves 23:59 8%

SFO · 1h 05m · leaves 05:15 10%

Afternoon and evening

ATL · 1h 12m · leaves 08:40 25%

ORD · 1h 00m · leaves 10:52 28%

PHL · 49m · leaves 12:44 29%

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.


Alaska AS 394 SEA 21:33 → MCO American AA 2593 MCO 08:35 → MIA Connection details →	2h 19m	9h 16m	97%	93%
Alaska AS 373 SEA 16:47 → SLC Delta DL 2040 SLC 23:00 → MIA Connection details →	3h 10m	9h 55m	98%	88%
Alaska AS 313 SEA 09:18 → DTW American AA 3358 DTW 18:57 → MIA Connection details →	2h 24m	9h 52m	95%	87%

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