Route on-time record
KOA to SEA: most on-time flights and the best time to fly
Kailua-Kona (Ellison Onizuka Kona International Airport at Keāhole) to Seattle (Seattle–Tacoma International Airport). 1,422 nonstop flights in Jun 2025 to May 2026, 86% arrived within 15 minutes and 2.3% were cancelled. The most reliable flight number was Delta 485 at 8:50 PM.
Flying on a specific date? We’ll adjust for the month, the weekday and the forecast.
KOA → SEA
Kailua-Kona to Seattle: 1,422 nonstop flights a year
On time (12 months)
86%
Cancelled
2.3%
avg delay 10 min
Best time to leave
6 to 9 PM
91% on time vs 73% noon to 3 PM
Most reliable airline
Delta
88% chance on time
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 485
8:50 PM → 5:46 AM5h 58m nonstop
Local times, typical schedule. Last flown 2026-05-31.
90%
chance on time
- On time (history)
- 93%
- Cancelled
- 2.3%
- Avg arrival delay
- 4 min
- Arrived on time 93% of the time (339 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (6 to 9 PM: 91% on time; Noon to 3 PM: 73%).
Strong track record · 339 flights
Find Delta 485 fares Opens this date on Aviasales#2 · Alaska 259
10:07 PM → 7:02 AM5h 55m nonstop
Local times, typical schedule. Last flown 2026-05-31.
88%
chance on time
- On time (history)
- 90%
- Cancelled
- 1.3%
- Avg arrival delay
- 4 min
- Arrived on time 90% of the time (152 flights, Jun 2025 to May 2026).
Moderate track record · 152 flights
Find Alaska 259 fares Opens this date on Aviasales#3 · Alaska 228
8:00 AM → 4:58 PM5h 58m nonstop
Local times, typical schedule. Last flown 2026-05-31. Same departure also flew as Alaska 319, 218; its record covers all of them.
87%
chance on time
- On time (history)
- 89%
- Cancelled
- 0.7%
- Avg arrival delay
- 7 min
- Arrived on time 89% of the time (152 flights, Jun 2025 to May 2026).
- Lands inside SEA's trouble window: 54% of its 68 ground stops and delay programs started between 4 PM and 10 PM.
Moderate track record · 152 flights
Find Alaska 228 fares Opens this date on Aviasales#4 · Alaska 205
11:59 AM → 8:55 PM5h 58m nonstop
Local times, typical schedule. Last flown 2026-05-31.
79%
chance on time
- On time (history)
- 80%
- Cancelled
- 0.0%
- Avg arrival delay
- 10 min
- Arrived on time 80% of the time (174 flights, Jun 2025 to May 2026).
- Never cancelled in 174 scheduled flights.
- Lands inside SEA's trouble window: 54% of its 68 ground stops and delay programs started between 4 PM and 10 PM.
- 50% of its delay minutes came from the plane arriving late from an earlier flight.
Moderate track record · 174 flights
Find Alaska 205 fares Opens this date on Aviasales
Airlines on this route
Season-adjusted chance of operating and arriving on time.
- Delta Air Lines88%
365 flights · 91% on time as flown · 2.6% cancel
- Alaska Airlines83%
1,057 flights · 85% on time as flown · 2.1% cancel
On time by departure time
All airlines, scheduled local departure, Jun 2025 to May 2026.
- Before 9 AM88%
282 flights · avg delay 11 min
- 9 AM to noon84%
333 flights · avg delay 14 min
- Noon to 3 PM73%
83 flights · avg delay 18 min
- 6 to 9 PM91%
170 flights · avg delay 4 min
- After 9 PM88%
554 flights · avg delay 7 min
Best day: Wednesday (89%). Worst: Saturday (84%).
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
- Late-arriving aircraft36%
- Airline (crew, maintenance, boarding)35%
- Air traffic control and airport volume26%
- Severe weather2%
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
KOA to SEA questions
- What time of day is best to fly KOA to SEA?
- 6 to 9 PM: 91% of flights arrived on time, against 73% for departures noon to 3 PM.
- Which airline is most on time from KOA to SEA?
- Delta, with a season-adjusted 88% chance of operating and arriving on time over 365 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 KOA to SEA?
- January (82% on time); the best was July (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 KOA
- SEA to KOA (return)
- KOA to HNL 85%
- KOA to LAX 86%
- KOA to OGG 87%
- KOA to SFO 83%
- KOA to SMF 90%
- KOA to PHX 93%
- KOA to DEN 91%
- KOA to LIH 93%
- KOA to LAS 95%
- KOA to SAN 71%
- KOA to PDX 74%
Live status: FAA delays and ground stops