Seattle (SEA) to Raleigh/Durham (RDU): On-Time Performance
Data through July 2026
The calendar drives reliability on SEA–RDU. March 2025 flights landed on schedule 97% of the time, but July 2025 dropped to 62% — a gap of 35 points. Across the full period the route averages 79% on-time against a national 78%.
- On-time
- 79%
- arrived <15 min late
- Avg delay
- 10 min
- completed flights
- Cancelled
- 0.6%
- Flights/day
- 2.5
- last 12 months
- Duration
- 5h 4m
- scheduled
- Distance
- 2,354 mi
Best airline from SEA to RDU
2 airlines flew this route regularly between 2024-07 and 2026-07.
| Airline | On-time | Avg delay | Cancelled | Flights |
|---|---|---|---|---|
| Delta Air Linesmost reliable | 80% | 11 min | 0.9% | 759 |
| Alaska Airlines | 79% | 9 min | 0.4% | 1,148 |
Monthly on-time trend
Best time to fly from SEA to RDU
Aim for departures around 10 a.m. (91% on-time); avoid 4 p.m. departures (69%).
By day of week
| Day | On-time | Avg delay |
|---|---|---|
| Monday | 74% | 14 min |
| Tuesdaybest | 86% | 7 min |
| Wednesday | 83% | 10 min |
| Thursday | 80% | 10 min |
| Friday | 77% | 10 min |
| Saturday | 80% | 8 min |
| Sunday | 76% | 11 min |
What causes delays on this route
Share of total delay minutes by cause, as reported by carriers to the US DOT.
- Late-arriving aircraft31%
- Airline operations42%
- National airspace system27%
- Weather1%
Frequently asked questions
- How often are flights from SEA to RDU delayed?
- 21% of SEA–RDU 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 10 minutes.
- Which airline is most reliable from SEA to RDU?
- Delta Air Lines has the best on-time record on this route at 80%, based on 759 flights. 2 airlines flew SEA–RDU frequently enough to compare in this period.
- What is the best time of day to fly from SEA to RDU?
- Departures around 10 a.m. have the best record (91% on-time), while departures around 4 p.m. have the worst (69%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
- How long is the flight from SEA to RDU?
- The scheduled SEA–RDU flight time averages 5h 4m over 2,354 miles. Actual arrival times vary — flights on this route land 15+ minutes late 21% of the time.
- How often are SEA to RDU flights cancelled?
- 0.6% of scheduled flights on this route were cancelled between 2024-07 and 2026-07, at or below the national rate of 1.6%.
- What is the worst month to fly from SEA to RDU?
- July 2025 was the roughest month in this dataset, with only 62% of arrivals on time. The best was March 2025 at 97%. If your dates are flexible, that 35-point gap is worth planning around.
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Based on 1,907 flights, 2024-07–2026-07. Source: US DOT Bureau of Transportation Statistics. Updated 2026-09-28.