Seattle (SEA) to Newark (EWR): On-Time Performance
Data through July 2026
When you fly SEA to EWR matters as much as anything else about the booking: the route swung from 90% on-time in April 2026 to just 52% in May 2025. Across the full period the route averages 79% on-time against a national 78%.
- On-time
- 79%
- arrived <15 min late
- Avg delay
- 15 min
- completed flights
- Cancelled
- 1.7%
- Flights/day
- 6.2
- last 12 months
- Duration
- 5h 21m
- scheduled
- Distance
- 2,402 mi
Best airline from SEA to EWR
2 airlines flew this route regularly between 2024-07 and 2026-07.
| Airline | On-time | Avg delay | Cancelled | Flights |
|---|---|---|---|---|
| United Airlinesmost reliable | 81% | 17 min | 1.6% | 2,033 |
| Alaska Airlines | 77% | 14 min | 1.8% | 2,324 |
Monthly on-time trend
Best time to fly from SEA to EWR
Aim for departures around 6 a.m. (91% on-time); avoid 10 a.m. departures (66%).
By day of week
| Day | On-time | Avg delay |
|---|---|---|
| Monday | 78% | 13 min |
| Tuesdaybest | 85% | 11 min |
| Wednesday | 82% | 13 min |
| Thursday | 75% | 16 min |
| Friday | 76% | 17 min |
| Saturday | 77% | 19 min |
| Sunday | 78% | 20 min |
What causes delays on this route
Share of total delay minutes by cause, as reported by carriers to the US DOT.
- Late-arriving aircraft22%
- Airline operations23%
- National airspace system48%
- Weather7%
Frequently asked questions
- How often are flights from SEA to EWR delayed?
- 21% of SEA–EWR flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-07 and 2026-07. The average arrival delay across completed flights was 15 minutes.
- Which airline is most reliable from SEA to EWR?
- United Airlines has the best on-time record on this route at 81%, based on 2,033 flights. 2 airlines flew SEA–EWR frequently enough to compare in this period.
- What is the best time of day to fly from SEA to EWR?
- Departures around 6 a.m. have the best record (91% on-time), while departures around 10 a.m. have the worst (66%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
- How long is the flight from SEA to EWR?
- The scheduled SEA–EWR flight time averages 5h 21m over 2,402 miles. Actual arrival times vary — flights on this route land 15+ minutes late 21% of the time.
- How often are SEA to EWR flights cancelled?
- 1.7% of scheduled flights on this route were cancelled between 2024-07 and 2026-07, slightly above the national rate of 1.6%.
- What is the worst month to fly from SEA to EWR?
- May 2025 was the roughest month in this dataset, with only 52% of arrivals on time. The best was April 2026 at 90%. If your dates are flexible, that 37-point gap is worth planning around.
Explore related pages
More routes from SEA
Other ways to fly to Newark (EWR)
Related guides
Based on 4,357 flights, 2024-07–2026-07. Source: US DOT Bureau of Transportation Statistics. Updated 2026-09-28.