Route reliability record
TPA→SEA
Tampa to Seattle
- Flights
- 975
- Period
- September 2025 to August 2026
- Distance
- 2,520 mi
- Carriers
- 2
This route sits in the middle of the pack with a C+. Close to three flights in four arrive on time by the DOT's definition, 3 points worse than the national rate of 77.3%. The late ones land about 50 minutes behind schedule. That rests on 975 TPA to SEA flights, with a median arrival right on schedule.
Best time to fly TPA to SEA: a 8am–11am departure, ideally on a Saturday. Flights in that window arrived on time 86.0% of the time and Saturday flights 80.9%, against 74.2% for the route overall.
The US average over the same twelve months is 77.3%, so there is little to separate this route from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
74.2%
Arrivals under 15 minutes late, of 959 completed flights
Avg delay
49 min
Across delayed arrivals only, not all flights
Cancelled
0.92%
National rate is 1.89%
Best carrier
Alaska
68.3% on time across 612 flights
These figures cover 975 flights between September 2025 and August 2026. On-time means an arrival less than 15 minutes after the scheduled gate time, the same threshold the Department of Transportation uses in its own reports. Cancelled and diverted flights are excluded from the on-time rate and counted separately, which is why the cancellation column matters on its own.
Fare search by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Carrier by carrier
Which airline is most reliable on TPA to SEA
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 |
|---|---|---|---|---|---|
| Delta Air Linesthin sample | 363 | 84.3% | 41 min | 0.83% | B+ |
| Alaska Airlines | 612 | 68.3% | 52 min | 0.98% | C+ |
Flight by flight
Flights on TPA to SEA
The flight numbers below flew this route at least 250 times in the period, busiest first. Each has its own record, with its schedule and delay causes.
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
The best time of day to leave
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 23 points, against half a point between the best and worst carrier.
- 5am–8am456 flights75.9%
- 8am–11am217 flights86.0%
- 11am–2pm—
- 2pm–5pm—
- 5pm–8pm302 flights63.2%
- 8pm–5am—
Scale runs 55% to 90%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 63.2% on time, against 86.0% for the 8am–11am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 5am–8am window is the busiest, with 456 flights scheduled in it.
Explore
Filter TPA to SEA by airline, time, month and day
Pick a breakdown and a carrier. The dashed mark on each row is the same slice for every US flight.
On TPA to SEA, the best departure window is 8am–11am at 86.0% on time and the worst is 5pm–8pm at 63.2%, a wide gap of 22.8 points. All US flights leaving 8am–11am ran 83.9%.
- 5–8am75.9%
- 8–11am86.0%
- 11am–2pm—
- 2–5pm—
- 5–8pm63.2%
- 8pm–5am—
best all US flightsScale 55% to 95%. Cells under 30 flights show a dash.
Across the year
When delays peak on this route
This route's year swings by 25 points from best month to worst, which is wide. An annual average tells you very little about the week you are actually flying, so read the strip rather than the headline if your dates are fixed.
February is the weak month at 63.0% on time, against 88.1% in November. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. May was the busiest month here, with 93 flights.
Across the week, Saturday is the strongest day at 80.9% on time and Friday the weakest at 67.6%, a spread of 13 points.
Delay causes
Why this route gets delayed
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 12,000 reported delay minutes.
- 35%Late-arriving aircraft
- 32%Carrier
- 30%National Airspace System
- 3%Extreme weather
- 0%Security
35% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 12,000 reported delay minutes here, that single category outweighs weather by 12 to one. The split is drawn from 12,144 reported delay minutes.
The practical consequence: the 8am–11am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 86.0% on time here.
Cancellations sit at 0.92% against a national 1.89%, which is ordinary. Diversions add another 0.72%.
Connections and stage length
What a delay here actually costs
6.0% of arrivals land an hour or more late, close to the national 8.3%, so a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last about 50 minutes, which a normal layover absorbs.
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 80.4% on time across 975 flights, 6 points above 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 6 points of difference.
One caution: this is a thin sample. 975 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.
Work out the risk of missing a connection in SEA after this flight
What to do with this
Booking this route
Put together: treat all of this as provisional. 975 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 74.2% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 959 completed flights over 12 months sit behind that.
Common questions
TPA to SEA questions
How often is TPA to SEA delayed?
About one flight in four arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 25.8% of the 975 flights in this analysis, against 22.7% nationally. Delayed flights are late by about 50 minutes on average.
How reliable is TPA to SEA compared with the rest of the country?
74.2% of flights arrive on time here against a national 77.3%, a difference of 3 points against it. That is worth a C+ on this site's grading scale.
What time of day has the fewest delays on TPA to SEA?
The 8am–11am departure window is the strongest at 86.0% on time. The 5pm–8pm window is the weakest at 63.2%, 23 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.
How bad are February delays on TPA to SEA?
February is the weakest month at 63.0% on time, compared with 88.1% in November. Across the year that is 25 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
- SEA to TPA — the return legseparate record
- Tampa International (TPA) delay statistics
- Seattle-Tacoma International (SEA) delay statistics
- Delta Air Lines on TPA to SEA84.3%
- Alaska Airlines on TPA to SEA68.3%
- TPA to ATL, a related route79.6%
- LAX to SEA, a related route85.0%
- TPA to ORD, a related route72.9%
- Delta Air Lines on-time record84.3%
- Alaska Airlines on-time record68.3%
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.05 million flight records
Direction matters. TPA to SEA and SEA to TPA are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Embed TPA to SEA’s on-time badge on your site
Paste this into a web page. The badge shows the current on-time rate, cancellation rate and grade, and updates every month. Preview it, or build a badge for another route or airport.
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.