Route on-time record
FLL to SEA: most on-time flights and the best time to fly
Fort Lauderdale (Fort Lauderdale Hollywood International Airport) to Seattle (Seattle–Tacoma International Airport). 826 nonstop flights in Jun 2025 to May 2026, 67% arrived within 15 minutes and 1.6% were cancelled. The most reliable flight number was Delta 356 at 8:55 AM.
Flying on a specific date? We’ll adjust for the month, the weekday and the forecast.
FLL → SEA
Fort Lauderdale to Seattle: 826 nonstop flights a year
On time (12 months)
67%
Cancelled
1.6%
avg delay 21 min
Best time to leave
Before 9 AM
71% on time vs 64% 6 to 9 PM
Most reliable airline
Delta
70% chance on time
Lowest nonstop fare seen in the next two months: $312 (Alaska 517 on 2026-11-03). 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 356
8:55 AM → 12:43 PM6h 40m nonstop
Local times, typical schedule. Last flown 2026-05-31.
71%
chance on time
- On time (history)
- 74%
- Cancelled
- 1.8%
- Avg arrival delay
- 16 min
- Arrived on time 74% of the time (159 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 71% on time; 6 to 9 PM: 64%).
- Departs outside FLL's trouble window (1 PM to 7 PM, when 70% of its 20 ground stops and delay programs started).
Moderate track record · 159 flights
Find Delta 356 fares Opens this date on Aviasales#2 · Alaska 517
5:54 PM → 9:44 PM6h 50m nonstop
Local times, typical schedule. Last flown 2026-05-31.
60%
chance on time
- On time (history)
- 60%
- Cancelled
- 1.6%
- Avg arrival delay
- 22 min
- Arrived on time 60% of the time (308 flights, Jun 2025 to May 2026).
- Departs inside FLL's trouble window: 70% of its 20 ground stops and delay programs started between 1 PM and 7 PM.
- Lands inside SEA's trouble window: 54% of its 68 ground stops and delay programs started between 4 PM and 10 PM.
Strong track record · 308 flights
Find Alaska 517 fares Opens this date on Aviasales
Airlines on this route
Season-adjusted chance of operating and arriving on time.
- Delta Air Lines70%
364 flights · 72% on time as flown · 1.6% cancel
- Alaska Airlines64%
462 flights · 64% on time as flown · 1.5% cancel
On time by departure time
All airlines, scheduled local departure, Jun 2025 to May 2026.
- Before 9 AM71%
346 flights · avg delay 18 min
- 3 to 6 PM65%
129 flights · avg delay 20 min
- 6 to 9 PM64%
351 flights · avg delay 25 min
Best day: Saturday (75%). Worst: Sunday (64%).
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 aircraft43%
- Airline (crew, maintenance, boarding)27%
- Air traffic control and airport volume26%
- Severe weather4%
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
FLL to SEA questions
- What time of day is best to fly FLL to SEA?
- Before 9 AM: 71% of flights arrived on time, against 64% 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 FLL to SEA?
- Delta, with a season-adjusted 70% 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 FLL to SEA?
- December (64% on time); the best was October (88%), 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 FLL
- SEA to FLL (return)
- FLL to ATL 71%
- FLL to EWR 70%
- FLL to LGA 66%
- FLL to JFK 69%
- FLL to BOS 66%
- FLL to ORD 69%
- FLL to PHL 73%
- FLL to BWI 73%
- FLL to CLT 78%
- FLL to DFW 72%
- FLL to IAH 82%
- FLL to DTW 73%
Most on-time flights from FLL on every route →
Live status: FAA delays and ground stops