Best Time to Fly DCA to SEA: On-Time Stats by Hour & Airline
Ronald Reagan Washington National → Seattle/Tacoma International
Data through July 2026 · Last updated October 18, 2026
Over the last 12 months, 74.4% of Washington (DCA) to Seattle (SEA) flights arrived on time (1,092 scheduled flights). That is 3.2 points below the national average of 77.6%.
Among 2 airlines, Alaska Airlines led with 77.8% on time and Delta Air Lines was last with 67.5%.
Over 24 months, Saturday was the most reliable day (84% on time) and December the worst month (58%).
The cancellation rate was 1.5% (US average 1.8%).
DCA to SEA 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 |
|---|---|---|---|---|
| Alaska Airlines | 77.8% | 49 min | 0.8% | 728 |
| Delta Air Lines | 67.5% | 94 min | 2.8% | 364 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly DCA to SEA
On-time arrival % by scheduled departure hour (local time), 1,966 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 8am–9am | 82.5% | 1.1% | 730 |
| 4pm–5pm | 70.7% | 2.6% | 508 |
| 5pm–6pm | 75.8% | 1.2% | 728 |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on DCA to SEA
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) | 84.4% | +6.0 pts | 3.0% | 33 |
| Christmas & New Year (Dec 20 - Jan 3) | 66.2% | -12.1 pts | 1.3% | 75 |
| Summer peak (Jun 15 - Aug 15) | 72.8% | -5.6 pts | 2.0% | 355 |
| All other days | 78.3% | — | 1.4% | 1,503 |
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).