LAS to SEA flight delays

LAS SEA Harry Reid to Seattle Tacoma · 867 miles

18,723 flights were scheduled from LAS to SEA over July 2023 through June 2026. Of the 18,558 that made the trip, 80.1% reached the gate less than 15 minutes behind schedule. These are arrival figures: “on time” means the flight reached the gate less than 15 minutes behind schedule. Arrivals are what decide whether you make the connection, so route and airline pages are scored on them rather than on pushback.

Data through June 2026 · Bureau of Transportation Statistics

The route in brief

Flights in the window
18,723
Arrived on time
80.1%
Cancelled
0.8%
Scheduled distance
867 miles

Cancellations are counted against everything scheduled. Diverted flights are counted with them rather than as very late arrivals, which is why the on-time share and the cancellation rate do not add up to everything that happened.

Airline by airline

Airlines with at least 100 flights on LAS–SEA, busiest first. Same route, same weather, same air traffic — which makes this the fairest comparison on the site.

Airline Arrived on time Typical delay Cancelled Flights
Alaska Airlines 79.2% 63 min 1.2% 8,125
Delta Air Lines 86.9% 73 min 0.4% 5,223
Southwest Airlines 70.6% 45 min 0.3% 2,954
Spirit Airlines 80.5% 62 min 0.7% 1,496
Frontier Airlines 80.1% 56 min 1.3% 853

Month by month

July was the month to avoid on LAS–SEA: 74.1% of flights arrived on time, against 87.6% in February. Each bar pools three years of that calendar month.

Share of flights that arrived on time, by calendar month. Best month in green, worst in amber. The hairline sits at the overall rate, 80.1%.
Arrival on-time share, LAS to SEA, by calendar month
Month Share flights that arrived on time Flights
January 82.2% 1,483
February 87.6% 1,351
March 82.7% 1,531
April 81.7% 1,519
May 78.1% 1,619
June 75.1% 1,558
July 74.1% 1,649
August 75.3% 1,652
September 78% 1,601
October 80.7% 1,689
November 85.9% 1,545
December 82.2% 1,526

Both ends of the route

A route’s record is built out of two airports’ habits. The hour-by-hour grid for each is on its own page.

LAS to SEA in one number

LAS → SEA

When a flight on this route was late, it was late by about 60 min.

July 2023–June 2026 · 18,723 flights

80.1% of flights arrived on time

Questions about LAS to SEA

Which airline is most reliable from LAS to SEA?
Delta Air Lines — its flights on this pairing arrived on time 86.9% of the time, with 5,223 scheduled. Southwest Airlines came in at 70.6% over 2,954 scheduled. Airlines with fewer than 100 flights on the route are not rated.
What is the worst month to fly LAS to SEA?
July, at 74.1% of arrivals on time, with 1,649 flights scheduled. February was the best of the year at 87.6%.
How late are LAS–SEA flights when they are late?
60 min on average, counting only the flights that arrived 15 minutes or more behind schedule. The on-time flights are left out of that average on purpose — mixing them in would flatter it.
How often is the LAS to SEA flight cancelled?
0.8% of scheduled flights on this route were cancelled, July 2023 through June 2026. Diverted flights are counted with the cancellations rather than as late arrivals.
Are these departure or arrival numbers?
Arrival. A flight counts as on time here if it reached the gate at SEA less than 15 minutes behind schedule. Airport pages score departures instead, because that is the number you can act on when you pick a booking time.