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 86% on time.

Nonstops


Delta	GEG	SEA	1h 24m	90%	0.7%	2,908	Flying now
Alaska	GEG	SEA	1h 15m	83%	1.5%	3,332	Flying now

Best connections, one ticket

Most reliable Quickest (80%+ on time)

Ranked by chance you reach Seattle on time. Total trip = scheduled departure to arrival, layover included. Layovers up to 4 hours. Pick a connection for the details.


Alaska Details →	GEG 05:00 → PDX 06:10AS 710	1h 09m Portland	PDX 07:19 → SEA 08:20AS 2420 · flown by Horizon	3h 20m	98%	94%
Southwest Details →	GEG 17:30 → SMF 19:25WN 1890	2h 30m Sacramento	SMF 21:55 → SEA 23:50WN 4985	6h 20m	96%	90%
Delta Details →	GEG 17:10 → SLC 19:59DL 1503	2h 46m Salt Lake City	SLC 22:45 → SEA 23:59DL 2998	6h 49m	98%	88%
Alaska Details →	GEG 08:53 → BOI 11:02AS 2031 · flown by Horizon	2h 04m Boise	BOI 13:06 → SEA 13:40AS 2235 · flown by Horizon	4h 47m	100%	87%
Alaska Details →	GEG 08:31 → PDX 09:46AS 3201 · flown by SkyWest	2h 17m Portland	PDX 12:03 → SEA 13:03AS 3078 · flown by SkyWest	4h 32m	100%	85%
Delta Details →	GEG 09:50 → SLC 12:41DL 4444 · flown by SkyWest	2h 33m Salt Lake City	SLC 15:14 → SEA 16:30DL 2817	6h 40m	100%	77%
Alaska Details →	GEG 12:42 → PDX 13:52AS 251	3h 38m Portland	PDX 17:30 → SEA 18:33AS 430	5h 51m	100%	76%
Alaska Details →	GEG 06:00 → BOI 08:07AS 2198 · flown by Horizon	3h 35m Boise	BOI 11:42 → SEA 12:16AS 2159 · flown by Horizon	6h 16m	100%	75%
Tight connection: often missed
Alaska Details →	GEG 15:16 → PDX 16:32AS 3202 · flown by SkyWest	58m Portland	PDX 17:30 → SEA 18:33AS 430	3h 17m	17%	13%
United Details →	GEG 19:07 → SFO 21:29UA 6042 · flown by SkyWest	1h 30m San Francisco	SFO 22:59 → SEA 01:29 +1UA 5579 · flown by SkyWest	6h 22m	18%	12%

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

PDX · 1h 09m · leaves 05:00 2%

DEN · 55m · leaves 06:00 4%

LAX · 55m · leaves 06:20 18%

Afternoon and evening

SLC · 51m · leaves 19:08 20%

PDX · 58m · leaves 15:16 83%

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 3201 GEG 08:31 → PDX Delta DL 3802 PDX 12:23 → SEA Connection details →	2h 37m	5h 03m	100%	86%
Alaska AS 251 GEG 12:42 → PDX Delta DL 3918 PDX 17:50 → SEA Connection details →	3h 58m	6h 23m	100%	84%
Alaska AS 2198 GEG 06:00 → BOI Delta DL 3678 BOI 11:55 → SEA Connection details →	3h 48m	6h 42m	99%	84%

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