EWR to SEA flight delays

EWR SEA Newark Liberty to Seattle Tacoma · 2,402 miles

6,154 flights were scheduled from EWR to SEA over July 2023 through June 2026. Of the 6,030 that made the trip, 74.3% 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
6,154
Arrived on time
74.3%
Cancelled
1.8%
Scheduled distance
2,402 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 EWR–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 73% 71 min 2.4% 3,205
United Airlines 75.7% 70 min 1.2% 2,949

Month by month

July was the month to avoid on EWR–SEA: 56.5% of flights arrived on time, against 83.2% in September. 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, 74.3%.
Arrival on-time share, EWR to SEA, by calendar month
Month Share flights that arrived on time Flights
January 81.2% 366
February 81.9% 321
March 70.8% 426
April 81.4% 452
May 76.8% 541
June 68% 605
July 56.5% 650
August 72.9% 661
September 83.2% 638
October 80.1% 565
November 74.9% 460
December 72.1% 469

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.

EWR to SEA in one number

EWR → SEA

When a flight on this route was late, it was late by about 70 min.

July 2023–June 2026 · 6,154 flights

74.3% of flights arrived on time

Questions about EWR to SEA

Which airline is most reliable from EWR to SEA?
United Airlines — its flights on this pairing arrived on time 75.7% of the time, with 2,949 scheduled. Alaska Airlines came in at 73% over 3,205 scheduled. Airlines with fewer than 100 flights on the route are not rated.
What is the worst month to fly EWR to SEA?
July, at 56.5% of arrivals on time, with 650 flights scheduled. September was the best of the year at 83.2%.
How late are EWR–SEA flights when they are late?
70 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 EWR to SEA flight cancelled?
1.8% 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.