Route reliability record
KTN→SEA
Ketchikan to Seattle
- Flights
- 1,304
- Period
- July 2025 to June 2026
- Distance
- 680 mi
- Carriers
- 1
This route lands a B, 5 points better than the national rate of 77.6%. About one flight in six arrives 15 minutes late or worse, and those flights are late by a little over an hour on average. That is a workable record, not a spotless one. That rests on 1,304 KTN to SEA flights, with a median arrival 11 minutes early.
Best time to fly KTN to SEA: a 8am–11am departure, ideally on a Tuesday. Flights in that window arrived on time 84.7% of the time and Tuesday flights 88.0%, against 82.6% for the route overall.
Set against the rest of the country, this route's record is 5 points better than the US average of 77.6%. That gap is worth roughly 50 fewer late arrivals for every thousand flights.
Key figures
On time
82.6%
Arrivals under 15 minutes late, of 1,269 completed flights
Avg delay
71 min
Across delayed arrivals only, not all flights
Cancelled
2.68%
National rate is 1.81%
Best carrier
Alaska
82.6% on time across 1,304 flights
These figures cover 1,304 flights between July 2025 and June 2026. The median arrival is 11 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.
Carrier by carrier
Which airline is most reliable on KTN 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 |
|---|---|---|---|---|---|
| Alaska Airlines | 1,304 | 82.6% | 71 min | 2.68% | B |
Flight by flight
Flights on KTN 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.
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 12 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am—
- 8am–11am362 flights84.7%
- 11am–2pm485 flights81.6%
- 2pm–5pm95 flights72.3%
- 5pm–8pm362 flights84.5%
- 8pm–5am—
Scale runs 65% to 90%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 84.7% of the time, against 72.3% for the afternoon window. That is 12 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 11am–2pm window is the busiest, with 485 flights scheduled in it.
Across the year
When delays peak on this route
This route's year swings by 26 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.
August is the worst month at 70.4% on time, 26 points below May, the best at 96.4%. 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. July was the busiest month here, with 155 flights.
Across the week, Tuesday is the strongest day at 88.0% on time and Monday the weakest at 74.9%. 13 points is a smaller lever than departure hour, but it is free.
Delay causes
Why this route gets delayed
One category carries most of the weight here. Late-arriving aircraft accounts for 68% of the 16,000 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.
- 68%Late-arriving aircraft
- 21%Carrier
- 8%National Airspace System
- 2%Extreme weather
- 2%Security
68% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 16,000 reported delay minutes here, that single category outweighs weather by 42 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 15,768 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 84.7% on time here.
Cancellations run at 2.68%, against 1.81% nationally. That is about one flight in 40 cancelled outright. A cancelled flight is invisible in every on-time figure on this page, so the punctuality numbers above describe only the flights that actually operated.
Connections and stage length
What a delay here actually costs
6.0% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last a little over an hour, which a normal layover absorbs.
The 680 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
The return leg is a different operation and performs like one: it runs 76.9% on time across 1,303 flights, 6 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 6 points of difference.
The sample behind these figures is 1,304 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.
Work out the risk of missing a connection in SEA after this flight
What to do with this
Booking this route
Put together: the calendar is the biggest lever here, not the carrier or the hour. May runs 96.4% on time and August 70.4%, a swing of 26 points. If the dates move at all, move them out of August before you think about anything else. 1,269 completed flights over 12 months sit behind that.
Common questions
KTN to SEA questions
How often is KTN to SEA delayed?
About one flight in six arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 17.4% of the 1,304 flights in this analysis, against 22.4% nationally. Delayed flights are late by a little over an hour on average.
How reliable is KTN to SEA compared with the rest of the country?
82.6% of flights arrive on time here against a national 77.6%, a difference of 5 points in its favour. That is worth a B on this site's grading scale.
What time of day has the fewest delays on KTN to SEA?
The 8am–11am departure window is the strongest at 84.7% on time. The 2pm–5pm window is the weakest at 72.3%, 12 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 August delays on KTN to SEA?
August is the weakest month at 70.4% on time, compared with 96.4% in May. Across the year that is 26 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 KTN — the return legseparate record
- Seattle-Tacoma International (SEA) delay statistics
- LAX to SEA, a related route85.4%
- PHX to SEA, a related route82.7%
- SFO to SEA, a related route73.7%
- Alaska Airlines on-time record82.6%
- The US routes with the most cancellations
- Why the first flight of the morning is statistically safest
Direction matters. KTN to SEA and SEA to KTN are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
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Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.