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 87% on time.

Nonstops


Delta	PSC	SEA	1h 15m	91%	0.3%	1,113	Flying now
Alaska	PSC	SEA	1h 09m	85%	1.6%	1,577	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 →	PSC 05:23 → PDX 06:18AS 3109 · flown by SkyWest	1h 01m Portland	PDX 07:19 → SEA 08:20AS 2420 · flown by Horizon	2h 57m	98%	94%
Delta Details →	PSC 17:21 → SLC 20:10DL 3728 · flown by SkyWest	2h 35m Salt Lake City	SLC 22:45 → SEA 23:59DL 2998	6h 38m	100%	91%
Delta Details →	PSC 06:00 → SLC 08:38DL 1645	2h 57m Salt Lake City	SLC 11:35 → SEA 12:52DL 2995	6h 52m	97%	85%
Delta Details →	PSC 10:00 → SLC 12:47DL 3694 · flown by SkyWest	2h 27m Salt Lake City	SLC 15:14 → SEA 16:30DL 2817	6h 30m	99%	76%
Delta Details →	PSC 13:50 → SLC 16:34DL 3892 · flown by SkyWest	46m Salt Lake City	SLC 17:20 → SEA 18:36DL 871	4h 46m	87%	71%
Alaska Details →	PSC 15:59 → PDX 16:50AS 2471 · flown by Horizon	2h 48m Portland	PDX 19:38 → SEA 20:33AS 2313 · flown by Horizon	4h 34m	98%	53%
Tight connection: often missed
United Details →	PSC 07:00 → SFO 09:06UA 6046 · flown by SkyWest	1h 09m San Francisco	SFO 10:15 → SEA 12:34UA 2192	5h 34m	20%	10%

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 01m · leaves 05:23 2%

SFO · 1h 09m · leaves 07:00 80%

Afternoon and evening

SLC · 46m · leaves 13:50 13%

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 3109 PSC 05:23 → PDX Delta DL 3953 PDX 09:30 → SEA Connection details →	3h 12m	5h 32m	100%	84%
Delta DL 1645 PSC 06:00 → SLC Alaska AS 796 SLC 11:17 → SEA Connection details →	2h 39m	6h 30m	97%	83%
Alaska AS 2471 PSC 15:59 → PDX Delta DL 3923 PDX 20:44 → SEA Connection details →	3h 54m	5h 57m	98%	76%

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