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

Connect in the morning. The same one-hour layover misses 4% of the time at 7 am and 1 time in 4 at 6 pm.

Nonstops


Delta	SLC	SEA	2h 17m	84%	0.5%	2,230	Flying now
Alaska	SLC	SEA	2h 19m	78%	1.2%	1,826	Flying now
Frontier	SLC	SEA	2h 21m	69%	3.3%	90	Not 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 (Seattle is 1 h behind Salt Lake City). Layovers up to 4 hours. Pick a connection for the details.


Delta Details →	SLC 07:55 → SJC 09:02DL 4026 · flown by SkyWest	2h 27m San Jose	SJC 11:29 → SEA 13:59DL 3736 · flown by SkyWest	7h 04m	100%	92%
Delta Details →	SLC 15:02 → EUG 16:02DL 4105 · flown by SkyWest	1h 43m Eugene	EUG 17:45 → SEA 19:05DL 4124 · flown by SkyWest	5h 03m	100%	90%
Delta Details →	SLC 08:15 → GEG 09:07DL 4444 · flown by SkyWest	2h 08m Spokane	GEG 11:15 → SEA 12:43DL 3824 · flown by SkyWest	5h 28m	100%	89%
Delta Details →	SLC 12:23 → PSC 13:09DL 3892 · flown by SkyWest	2h 16m Pasco	PSC 15:25 → SEA 16:40DL 3891 · flown by SkyWest	5h 17m	99%	89%
Delta Details →	SLC 08:15 → BOI 09:29DL 1744	2h 26m Boise	BOI 11:55 → SEA 12:42DL 3678 · flown by SkyWest	5h 27m	99%	89%
Delta Details →	SLC 08:10 → SMF 08:55DL 1367	2h 39m Sacramento	SMF 11:34 → SEA 13:45DL 3881 · flown by SkyWest	6h 38m	99%	88%
Delta Details →	SLC 08:25 → LAS 08:53DL 1698	2h 06m Las Vegas	LAS 10:59 → SEA 13:51DL 2922	6h 26m	99%	88%
Delta Details →	SLC 07:45 → SAN 08:42DL 1177	2h 23m San Diego	SAN 11:05 → SEA 14:21DL 2508	7h 36m	99%	87%
Tight connection: often missed
Alaska Details →	SLC 19:39 → PDX 20:43AS 3280 · flown by SkyWest	47m Portland	PDX 21:30 → SEA 22:27AS 2421 · flown by Horizon	3h 48m	63%	57%
United Details →	SLC 16:21 → SFO 17:23UA 1955	1h 05m San Francisco	SFO 18:28 → SEA 20:53UA 1577	5h 32m	64%	44%
Southwest Details →	SLC 16:45 → DEN 18:15WN 3740	1h 35m Denver	DEN 19:50 → SEA 21:50WN 1716	6h 05m	70%	23%

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 08:20 <1%

SAN · 1h 19m · leaves 07:40 3%

DEN · 1h 07m · leaves 05:15 4%

Afternoon and evening

PDX · 47m · leaves 19:39 37%

LAS · 1h 00m · leaves 20:30 42%

SMF · 1h 00m · leaves 20:15 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.


Alaska AS 3004 SLC 08:20 → PDX Delta DL 3818 PDX 11:20 → SEA Connection details →	1h 54m	5h 16m	100%	91%
Delta DL 4444 SLC 08:15 → GEG Alaska AS 2262 GEG 11:40 → SEA Connection details →	2h 33m	5h 35m	100%	88%
Southwest WN 4981 SLC 05:45 → SMF Alaska AS 1468 SMF 10:23 → SEA Connection details →	3h 58m	7h 37m	98%	88%

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