Best Time to Fly SEA to EWR: On-Time Stats by Hour & Airline
Seattle/Tacoma International → Newark Liberty International
Data through July 2026 · Last updated October 18, 2026
Over the last 12 months, 82.4% of Seattle (SEA) to Newark (EWR) flights arrived on time (2,264 scheduled flights). That is 4.8 points above the national average of 77.6%.
United Airlines was the most punctual of the 2 airlines on the route at 83.4%, while Alaska Airlines trailed at 81.7%.
February has been the best month (86% on time) and Thursday the weakest day of the week (75%).
1.9% of flights were cancelled, versus 1.8% nationally.
SEA to EWR on-time performance by airline
Last 12 months. Airlines with fewer than 30 completed flights are marked “limited data”.
| Airline | On time | Avg delay when late | Cancelled | Flights |
|---|---|---|---|---|
| United Airlines | 83.4% | 93 min | 1.6% | 996 |
| Alaska Airlines | 81.7% | 52 min | 2.2% | 1,268 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly SEA to EWR
On-time arrival % by scheduled departure hour (local time), 4,141 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 12am–1am | Limited data | 2 | |
| 6am–7am | 91.8% | 1.3% | 690 |
| 7am–8am | 88.7% | 3.2% | 374 |
| 8am–9am | 83.2% | 2.3% | 304 |
| 9am–10am | 82.2% | 0.0% | 107 |
| 10am–11am | 67.3% | 2.6% | 566 |
| 11am–12pm | 69.7% | 0.8% | 123 |
| 12pm–1pm | 71.7% | 1.7% | 241 |
| 1pm–2pm | 74.3% | 2.1% | 142 |
| 2pm–3pm | 73.8% | 0.0% | 149 |
| 3pm–4pm | 67.9% | 2.1% | 144 |
| 8pm–9pm | Limited data | 1 | |
| 9pm–10pm | 79.2% | 0.3% | 289 |
| 10pm–11pm | 78.0% | 0.7% | 549 |
| 11pm–12am | 83.6% | 1.7% | 460 |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on SEA to EWR
On-time arrivals during holiday periods compared with all other days, last 24 months.
| Period | On time | vs other days | Cancelled | Flights |
|---|---|---|---|---|
| Thanksgiving week (Tue before to Mon after) | 82.1% | -0.0 pts | 1.5% | 68 |
| Christmas & New Year (Dec 20 - Jan 3) | 83.2% | +1.1 pts | 0.6% | 156 |
| Summer peak (Jun 15 - Aug 15) | 70.8% | -11.3 pts | 3.1% | 892 |
| All other days | 82.1% | — | 1.2% | 3,025 |
Monthly on-time trend
On-time arrival % each month, with the 12-month US average for reference.
What causes delays on this route
Share of reported delay minutes, last 12 months (BTS cause categories).