Newark (EWR) to Seattle (SEA): On-Time Performance
Data through May 2026
Newark (EWR) to Seattle (SEA) effectively runs on two schedules. In April 2026, 91% of arrivals were on time; in December 2025 that fell to 45% — a 45-point seasonal swing. Across the full period the route averages 73% on-time against a national 78%. Morning departures also hold up better than evening ones (80% vs 61%), which matters most in the rough months.
- On-time
- 73%
- arrived <15 min late
- Avg delay
- 20 min
- completed flights
- Cancelled
- 1.8%
- Flights/day
- 6.0
- last 12 months
- Duration
- 6h 12m
- scheduled
- Distance
- 2,402 mi
Best airline from EWR to SEA
2 airlines flew this route regularly between 2024-06 and 2026-05.
| Airline | On-time | Avg delay | Cancelled | Flights |
|---|---|---|---|---|
| United Airlinesmost reliable | 76% | 16 min | 1.2% | 1,925 |
| Alaska Airlines | 70% | 23 min | 2.3% | 2,170 |
Monthly on-time trend
Best time to fly from EWR to SEA
Aim for departures around 3 p.m. (84% on-time); avoid 7 p.m. departures (59%).
By day of week
| Day | On-time | Avg delay |
|---|---|---|
| Monday | 74% | 21 min |
| Tuesdaybest | 79% | 12 min |
| Wednesday | 76% | 19 min |
| Thursday | 71% | 20 min |
| Friday | 68% | 24 min |
| Saturday | 70% | 21 min |
| Sunday | 71% | 22 min |
What causes delays on this route
Share of total delay minutes by cause, as reported by carriers to the US DOT.
- Late-arriving aircraft45%
- Airline operations17%
- National airspace system31%
- Weather6%
- Security1%
Frequently asked questions
- How often are flights from EWR to SEA delayed?
- 27% of EWR–SEA flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-06 and 2026-05. The average arrival delay across completed flights was 20 minutes.
- Which airline is most reliable from EWR to SEA?
- United Airlines has the best on-time record on this route at 76%, based on 1,925 flights. 2 airlines flew EWR–SEA frequently enough to compare in this period.
- What is the best time of day to fly from EWR to SEA?
- Departures around 3 p.m. have the best record (84% on-time), while departures around 7 p.m. have the worst (59%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
- How long is the flight from EWR to SEA?
- The scheduled EWR–SEA flight time averages 6h 12m over 2,402 miles. Actual arrival times vary — flights on this route land 15+ minutes late 27% of the time.
- How often are EWR to SEA flights cancelled?
- 1.8% of scheduled flights on this route were cancelled between 2024-06 and 2026-05, slightly above the national rate of 1.6%.
- What is the worst month to fly from EWR to SEA?
- December 2025 was the roughest month in this dataset, with only 45% of arrivals on time. The best was April 2026 at 91%. If your dates are flexible, that 45-point gap is worth planning around.
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Based on 4,095 flights, 2024-06–2026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.