Route on-time record
RDU to SEA: most on-time flights and the best time to fly
Raleigh/Durham (Raleigh-Durham International Airport) to Seattle (Seattle–Tacoma International Airport). 919 nonstop flights in Jun 2025 to May 2026, 76% arrived within 15 minutes and 1.5% were cancelled. The most reliable flight number was Delta 354 at 6:59 AM.
Flying on a specific date? We’ll adjust for the month, the weekday and the forecast.
RDU → SEA
Raleigh/Durham to Seattle: 919 nonstop flights a year
On time (12 months)
76%
Cancelled
1.5%
avg delay 12 min
Best time to leave
Before 9 AM
80% on time vs 68% 6 to 9 PM
Most reliable airline
Delta
82% chance on time
Lowest nonstop fare seen in the next two months: $637 (Alaska 672 on 2026-10-24). Fares open on our travel partner (Aviasales). Pick the flight number you chose here.
Most reliable nonstop flights
Ranked by the chance the flight operates and arrives within 15 minutes of schedule, from Jun 2025 to May 2026 records.
#1 · Delta 354
6:59 AM → 9:59 AM5h 50m nonstop
Local times, typical schedule. Last flown 2026-05-31.
84%
chance on time
- On time (history)
- 85%
- Cancelled
- 1.1%
- Avg arrival delay
- 9 min
- Arrived on time 85% of the time (340 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 80% on time; 6 to 9 PM: 68%).
- Departs outside RDU's trouble window (11 AM to 5 PM, when 57% of its 14 ground stops and delay programs started).
Strong track record · 340 flights
Find Delta 354 fares Opens this date on Aviasales#2 · Alaska 434
7:42 AM → 10:40 AM5h 58m nonstop
Local times, typical schedule. Last flown 2026-05-31.
76%
chance on time
- On time (history)
- 79%
- Cancelled
- 0.0%
- Avg arrival delay
- 10 min
- Arrived on time 79% of the time (19 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 80% on time; 6 to 9 PM: 68%).
- Departs outside RDU's trouble window (11 AM to 5 PM, when 57% of its 14 ground stops and delay programs started).
- 55% of its delay minutes came from the plane arriving late from an earlier flight.
Limited track record · 19 flights
Find Alaska 434 fares Opens this date on Aviasales#3 · Alaska 670
7:35 AM → 10:40 AM6h 05m nonstop
Local times, typical schedule. Last flown 2026-05-12.
69%
chance on time
- On time (history)
- 66%
- Cancelled
- 0.0%
- Avg arrival delay
- 15 min
- Arrived on time 66% of the time (79 flights, Jun 2025 to May 2026).
- Never cancelled in 79 scheduled flights.
- Leaves in this route's most on-time window (Before 9 AM: 80% on time; 6 to 9 PM: 68%).
- Departs outside RDU's trouble window (11 AM to 5 PM, when 57% of its 14 ground stops and delay programs started).
Moderate track record · 79 flights
Find Alaska 670 fares Opens this date on Aviasales#4 · Alaska 572
7:08 PM → 10:03 PM6h 04m nonstop
Local times, typical schedule. Last flown 2026-05-31.
68%
chance on time
- On time (history)
- 69%
- Cancelled
- 1.8%
- Avg arrival delay
- 16 min
- Arrived on time 69% of the time (323 flights, Jun 2025 to May 2026).
- Leaves in this route's least on-time window (6 to 9 PM: 68% on time; Before 9 AM: 80%).
- Departs outside RDU's trouble window (11 AM to 5 PM, when 57% of its 14 ground stops and delay programs started).
Strong track record · 323 flights
Find Alaska 572 fares Opens this date on Aviasales
Airlines on this route
Season-adjusted chance of operating and arriving on time.
- Delta Air Lines82%
364 flights · 85% on time as flown · 1.4% cancel
- Alaska Airlines70%
555 flights · 71% on time as flown · 1.6% cancel
On time by departure time
All airlines, scheduled local departure, Jun 2025 to May 2026.
- Before 9 AM80%
588 flights · avg delay 10 min
- 3 to 6 PM75%
33 flights · avg delay 12 min
- 6 to 9 PM68%
298 flights · avg delay 16 min
Best day: Saturday (84%). Worst: Monday (76%).
On time by month
All airlines, Jun 2023 to May 2026. Several years per month, so one stormy season doesn't define a month. Travel-month estimates use this seasonal pattern.
What delays this route
- Air traffic control and airport volume37%
- Airline (crew, maintenance, boarding)34%
- Late-arriving aircraft24%
- Severe weather4%
- Security1%
Share of delay minutes by the cause airlines report to the US DOT.
Historical odds, not a guarantee. Built from the US DOT Bureau of Transportation Statistics on-time reports (Jun 2025 to May 2026), FAA ground stop and delay program advisories, and 20 years of airport weather observations. Covers US airlines that report to the DOT; schedules are flights operated recently, so confirm times when you book. ATIS Alerts is not affiliated with any airline. Fares are what Aviasales travelers saw in recent searches (USD, one way, 1 adult), not live quotes; the partner site shows the current price. Fare links go to our travel partner and may earn us a commission at no cost to you. Affiliate disclosure
RDU to SEA questions
- What time of day is best to fly RDU to SEA?
- Before 9 AM: 80% of flights arrived on time, against 68% for departures 6 to 9 PM. Later flights inherit delays from earlier ones, so the first departures of the day usually run best.
- Which airline is most on time from RDU to SEA?
- Delta, with a season-adjusted 82% chance of operating and arriving on time over 364 flights. The adjustment compares each airline with what the route did in the months it flew, so a carrier that skipped a stormy month gets no free credit.
- What is the worst month for delays on RDU to SEA?
- December (73% on time); the best was November (89%), averaged over Jun 2023 to May 2026.
- Is this a prediction for my flight?
- No. These are historical odds from the US DOT on-time reports, FAA advisories and airport weather records. Check your flight status and the FAA delay board on the day you fly.
More routes from RDU
- SEA to RDU (return)
- RDU to ATL 87%
- RDU to ORD 74%
- RDU to CLT 82%
- RDU to BOS 78%
- RDU to LGA 69%
- RDU to MCO 78%
- RDU to PHL 73%
- RDU to JFK 75%
- RDU to MIA 76%
- RDU to DFW 77%
- RDU to BNA 80%
- RDU to EWR 74%
Most on-time flights from RDU on every route →
Live status: FAA delays and ground stops