78% of flights from Seattle to Fort Lauderdale arrived on time over the past 12 months. That is about the typical U.S. route. The 8 a.m. departures ran on time 82% of the time; the 11 a.m. ones 63%. Most reliable airline: Alaska Airlines (81%). 6% of flights arrived more than an hour late or not at all.
How late?
The on-time rate treats a flight 20 minutes late the same as one 5 hours late. Here's the split for SEA → FLL: when a flight was late, it was under 45 minutes late 70% of the time. About 1 in 23 flights landed an hour or more late, and 1 in 207 three hours or more; 0.7% were cancelled outright.
- On time or early78%
- 15–30 min late11%
- 30–60 min late5.8%
- 1–2 hours late3.1%
- 2–3 hours late0.7%
- 3+ hours late0.5%
- Diverted0.5%
- Cancelled0.7%
Share of all 826 scheduled flights, past 12 months, by arrival time against schedule.
By airline
| Airline | Flights | On time | Cancelled | Typical arrival | 1h+ late | Avg when late | Operated by |
|---|---|---|---|---|---|---|---|
| Alaska Airlines | 462 | 81% | 0.2% | −9 min | 3.5% | +44 min | Alaska Airlines |
| Delta Air Lines | 364 | 74% | 1.4% | −2 min | 5.5% | +47 min | Delta Air Lines |
Airline = the name on the ticket. Regional flights (e.g. "Delta Connection") count under the ticketing airline, and the operator is listed.
Best time of day to fly
On-time rate by scheduled departure hour (local time at SEA). Delays build through the day as late planes knock on, so early flights usually do best.
By airline and hour
| Departs | Alaska Airlines | Delta Air Lines |
|---|---|---|
| 8 a.m. | 82% | — |
| 11 a.m. | — | 63% |
By month
Each calendar month pooled over 2023–2026. Best: October (88%). Worst: January (70%).
By day of week
| Day | Flights | On time | Cancelled |
|---|---|---|---|
| Monday | 123 | 76% | 0.8% |
| Tuesday | 113 | 84% | 0.0% |
| Wednesday | 114 | 91% | 0.0% |
| Thursday | 118 | 77% | 0.9% |
| Friday | 121 | 69% | 0.8% |
| Saturday | 116 | 78% | 0.9% |
| Sunday | 121 | 69% | 1.7% |
Why flights were late
Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.
Cancellations: airline 5 · weather 1
Month by month
Not enough months with data to draw a trend.
Flight numbers on this route
Regular flights with at least 120 scheduled trips in the past year. Sorted by departure time.
| Flight | Departs | Flights | On time | Cancelled | Typical arrival | Operated by |
|---|---|---|---|---|---|---|
| AS 516 | 8:23 a.m. | 337 | 82% | 0.3% | −11 min | Alaska Airlines |
| DL 338 | 11:55 a.m. | 364 | 74% | 1.4% | −2 min | Delta Air Lines |
Worst days in the past year
| Date | Flights | On time | Cancelled |
|---|---|---|---|
| Mar 13, 2026 | 3 | 0% | 1 |
| Dec 28, 2025 | 3 | 0% | 0 |
| Nov 29, 2025 | 3 | 0% | 0 |
| Dec 25, 2025 | 3 | 0% | 0 |
| Feb 12, 2026 | 3 | 33% | 0 |
Nearby airport alternatives
Other ways to make the same trip, using airports within 60 miles of Seattle or Fort Lauderdale. None has been clearly more reliable than SEA → FLL.
| Route | Flights | On time | Cancelled |
|---|---|---|---|
| SEA → FLL (this route) | 826 | 78% | 0.7% |
| SEA → MIA Seattle-Tacoma to Miami | 1,231 | 79% | 0.8% |
Questions
How often are flights from SEA to FLL on time?
78% of 826 scheduled flights from Seattle, WA to Fort Lauderdale, FL arrived within 15 minutes of schedule between September 2025 and August 2026. 0.7% were cancelled.
What is the best time of day to fly SEA to FLL?
Flights scheduled to leave at 8 a.m. were the most reliable (82% on time). The 11 a.m. departures were the least (63%).
Which airline is most on time from SEA to FLL?
Alaska Airlines: 81% of its 462 flights on the route arrived on time. Delta Air Lines: 74%.
What month has the most delays from SEA to FLL?
January (70% on time). The best month is October (88%), over 2023–2026.
Related
- FLL → SEA (return)
- Seattle-Tacoma (SEA) delays by hour
- Flights into Fort Lauderdale (FLL)
- Alaska Airlines on-time record
- Delta Air Lines on-time record
- Connecting off this flight? Check the risk
Domestic flights by the airlines that report to the U.S. DOT, plus their regional partners. "On time" means arriving less than 15 minutes after schedule; cancelled and diverted flights count as not on time. Past performance is a guide, not a forecast. Method.