Carrier route record
ASSEA→TPA
Alaska Airlines · Seattle to Tampa
- Flights
- 612
- Period
- September 2025 to August 2026
- Share of route
- 63%
- Carriers
- 2
Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with Alaska Airlines.
Alaska on SEA to TPA lands a B+, 4 points better than the national rate of 77.3%. About one flight in five arrives 15 minutes late or worse, and those flights are late by roughly 50 minutes on average. That rests on 612 flights, with a median arrival 9 minutes early.
Set against the rest of the country, Alaska's SEA to TPA record is 4 points better than the US average of 77.3%. That gap is worth roughly 40 fewer late arrivals for every thousand flights.
Key figures
On time
81.3%
Arrivals under 15 minutes late, of 605 completed flights
Avg delay
48 min
Across delayed arrivals only, not all flights
Cancelled
0.49%
National rate is 1.89%
Whole route
80.4%
Every carrier on SEA to TPA, 975 flights
These figures cover 612 flights between September 2025 and August 2026. The median arrival is 9 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.
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Carrier by carrier
Alaska against every carrier on SEA to TPA
Alaska flew 612 of the 975 flights on SEA to TPA, most of the route. Its 81.3% on time is about level with the route as a whole at 80.4%. Ranked by on-time rate it is first of two carriers on the route, where the range runs from Alaska at 81.3% to Delta at 78.7%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Alaska Airlines (this page) | 612 | 81.3% | 48 min | 0.49% | B+ |
| Delta Air Linesthin sample | 363 | 78.7% | 57 min | 0.55% | B+ |
Flight by flight
Alaska flight numbers on SEA to TPA
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Departure window
When Alaska runs best on this route
Departure time is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 612 flights.
- 5am–8am—
- 8am–11am365 flights80.7%
- 11am–2pm—
- 2pm–5pm—
- 5pm–8pm—
- 8pm–5am247 flights82.2%
Scale runs 70% to 90%. Rows with fewer than 30 flights show a dash.
The overnight block holds up unusually well at 82.2% on time across 247 flights. Red-eyes fly into empty airspace and empty gates, and they are the first rotation of the aircraft's day rather than the last. The 8am–11am window is the busiest, with 365 flights scheduled in it.
Across the year
Alaska on SEA to TPA through the year
August is the worst month at 64.9% on time, 33 points below February, the best at 97.8%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. May was the busiest month here, with 61 flights.
Across the week, Saturday is the strongest day at 85.0% on time and Sunday the weakest at 73.0%, a spread of 12 points.
Arrival by arrival
How late Alaska on SEA to TPA runs when it is late
Alaska on SEA to TPA often beats the schedule: 227 of 605 completed flights, 38%, arrived 15 minutes or more early. The 113 late arrivals split 56 under half an hour, 35 between 30 and 60 minutes, and 22 an hour or more.
- 15+ min early227 flights37.5%
- Within 15 min265 flights43.8%
- 15–29 min late56 flights9.3%
- 30–59 min late35 flights5.8%
- 1–2 hours late14 flights2.3%
- 2+ hours late8 flights1.3%
Scale runs 0% to 100%.
Share of 605 completed flights by arrival against schedule.
A late pushback is often recovered here: of 129 departures that left 15 minutes late or more, 49 still arrived on time. In the other direction, 33 flights left on time yet arrived 15 minutes late or more, so that delay built up after pushback: in the air, in a holding pattern or on the ground at TPA.
The worst days
Worst days for Alaska on SEA to TPA
The latest arrival of the period was on 4 October 2025, 7 hours 18 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). The same cause led on five of the five worst days.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 4 October 2025 | 7 hours 18 minutes | Carrier |
| 12 July 2026 | 3 hours 38 minutes | Carrier |
| 5 March 2026 | 3 hours 17 minutes | Carrier |
| 18 August 2026 | 3 hours 11 minutes | Carrier |
| 27 May 2026 | 2 hours 23 minutes | Carrier |
Delay causes
Why Alaska runs late on this route
Carrier accounts for 56% of the 5,431 delay minutes carriers reported here, and the remaining four split what is left.
- 56%Carrier
- 23%National Airspace System
- 20%Late-arriving aircraft
- 1%Extreme weather
The largest share of delay minutes, 56%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 3,051 of the 5,431 delay minutes reported here. The split is drawn from 5,431 reported delay minutes.
Cancellations are rare at 0.49%, below the national 1.89% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.
Connections and stage length
What a delay here costs
Badly late arrivals are rare here: only 3.6% land an hour or more behind schedule, against 8.3% nationally. Connections built on this flight are about as safe as US domestic connections get, though a cancelled flight still ignores every layover you give it.
At 2,520 miles this is transcontinental flying, and long routes get a quiet structural advantage. Scheduled block time on a flight this length carries more padding in absolute minutes, so a twenty-minute late departure often still becomes an on-time arrival. Read the on-time rate here as slightly flattering next to a short-haul route with the same operational quality.
The return leg is a different operation and performs like one: it runs 68.3% on time across 612 flights, 13 points below this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 13 points of difference.
One caution: this is a thin sample. 612 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.
What to do with this
Booking Alaska on SEA to TPA
Put together: treat all of this as provisional. 612 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 81.3% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 605 completed flights over 12 months sit behind that.
Related
Where to go next
- SEA to TPA, every carrier
- Alaska on TPA to SEA, the return leg
- Delta Air Lines on SEA to TPA78.7%
- Alaska Airlines network-wide record
- Seattle-Tacoma International (SEA) delay statistics
- Tampa International (TPA) delay statistics
- Worst months to fly in the US, ranked by the data
- How to read this site: grades, sample sizes, and honest caveats
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.