FlightRecord

Seattle (SEA) to Raleigh/Durham (RDU): On-Time Performance

Data through May 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%. Morning departures also hold up better than evening ones (82% vs 71%), which matters most in the rough months.

On-time
79%
arrived <15 min late
Avg delay
10 min
completed flights
Cancelled
0.7%
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 2024-06 and 2026-05.

AirlineOn-timeAvg delayCancelledFlights
Delta Air Linesmost reliable81%10 min1.0%728
Alaska Airlines78%10 min0.5%1,087

Monthly on-time trend

Monthly on-time percentage for SEA to RDU flights50%75%100%June 2024: 78% on-time (90 flights)78Jun 2024July 2024: 75% on-time (93 flights)75August 2024: 74% on-time (93 flights)74September 2024: 79% on-time (89 flights)79Sep 2024October 2024: 82% on-time (62 flights)82November 2024: 93% on-time (58 flights)93December 2024: 76% on-time (76 flights)76Dec 2024January 2025: 90% on-time (59 flights)90February 2025: 92% on-time (52 flights)92March 2025: 97% on-time (62 flights)97Mar 2025April 2025: 84% on-time (69 flights)84May 2025: 73% on-time (93 flights)73June 2025: 72% on-time (90 flights)72Jun 2025July 2025: 62% on-time (93 flights)62August 2025: 66% on-time (88 flights)66September 2025: 75% on-time (77 flights)75Sep 2025October 2025: 88% on-time (64 flights)88November 2025: 78% on-time (67 flights)78December 2025: 79% on-time (73 flights)79Dec 2025January 2026: 89% on-time (66 flights)89February 2026: 82% on-time (56 flights)82March 2026: 83% on-time (71 flights)83Mar 2026April 2026: 82% on-time (81 flights)82May 2026: 82% on-time (93 flights)82

Best time to fly from SEA to RDU

Aim for departures around 10 a.m. (91% on-time); avoid 9 p.m. departures (67%).

On-time percentage by scheduled departure hour, SEA to RDU8 a.m.: 83% on-time (270 flights)89 a.m.: 80% on-time (411 flights)910 a.m.: 91% on-time (36 flights)103 p.m.: 82% on-time (650 flights)154 p.m.: 71% on-time (49 flights)169 p.m.: 67% on-time (285 flights)2110 p.m.: 83% on-time (109 flights)22scheduled departure hour

By day of week

DayOn-timeAvg delay
Monday73%15 min
Tuesdaybest87%6 min
Wednesday84%10 min
Thursday80%10 min
Friday76%11 min
Saturday80%8 min
Sunday76%10 min

What causes delays on this route

Share of total delay minutes by cause, as reported by carriers to the US DOT.

  • Late-arriving aircraft30%
  • Airline operations44%
  • National airspace system25%
  • 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 2024-06 and 2026-05. 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 81%, based on 728 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 9 p.m. have the worst (67%). 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?
0.7% of scheduled flights on this route were cancelled between 2024-06 and 2026-05, 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.

Based on 1,815 flights, 2024-062026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.