Carrier route record
ASJFK→SEA
Alaska Airlines · New York to Seattle
- Flights
- 1,402
- Period
- July 2025 to June 2026
- Share of route
- 48%
- Carriers
- 3
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Alaska Airlines.
Alaska on JFK to SEA draws a C. About one flight in three arrives at least 15 minutes late, and the typical late arrival is about an hour behind schedule. Build slack into anything you connect to. That rests on 1,402 flights, with a median arrival 2 minutes late.
The national on-time rate over the same period is 77.6%, so Alaska on JFK to SEA runs 11 points behind the country as a whole. Across a thousand flights that is about 114 extra late arrivals.
Key figures
On time
66.2%
Arrivals under 15 minutes late, of 1,356 completed flights
Avg delay
61 min
Across delayed arrivals only, not all flights
Cancelled
3.00%
National rate is 1.81%
Whole route
69.7%
Every carrier on JFK to SEA, 2,906 flights
These figures cover 1,402 flights between July 2025 and June 2026. Beyond the headline rate, 9.9% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Carrier by carrier
Alaska against every carrier on JFK to SEA
Alaska flew 1,402 of the 2,906 flights on JFK to SEA, about 48% of it. Its 66.2% on time is 4 points worse than the route as a whole, which runs 69.7%. Ranked by on-time rate it is last of three carriers on the route, where the range runs from Delta at 73.2% to Alaska at 66.2%. 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 |
|---|---|---|---|---|---|
| Delta Air Lines | 1,338 | 73.2% | 57 min | 2.32% | C |
| JetBlue Airwaysthin sample | 166 | 71.3% | 98 min | 1.20% | C |
| Alaska Airlines (this page) | 1,402 | 66.2% | 61 min | 3.00% | C |
Flight by flight
Alaska flight numbers on JFK to SEA
Departure window
When Alaska runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 24 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–8am359 flights68.5%
- 8am–11am—
- 11am–2pm329 flights75.5%
- 2pm–5pm316 flights69.3%
- 5pm–8pm349 flights51.4%
- 8pm–5am49 flights68.8%
Scale runs 45% to 80%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 51.4% on time, against 75.5% for the 11am–2pm 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 359 flights scheduled in it.
Across the year
Alaska on JFK to SEA through the year
December is the weak month at 37.5% on time, against 82.8% in April. 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. July was the busiest month here, with 124 flights.
Across the week, Saturday is the strongest day at 70.2% on time and Friday the weakest at 63.5%. 7 points is a smaller lever than departure hour, but it is free.
Delay causes
Why Alaska runs late on this route
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 28,000 reported delay minutes.
- 42%National Airspace System
- 25%Late-arriving aircraft
- 24%Carrier
- 7%Extreme weather
- 1%Security
42% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 12,000 minutes out of 28,000, against a national NAS share of 21%. The split is drawn from 27,809 reported delay minutes.
Cancellations run at 3.00%, against 1.81% nationally. That is roughly one flight in 30 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 costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 9.9% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.
At 2,422 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 71.6% on time across 1,403 flights, 5 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 5 points of difference.
The sample behind these figures is 1,402 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.
What to do with this
Booking Alaska on JFK to SEA
Put together: the delay figures matter less here than the 3.00% cancellation rate. A late arrival costs you about an hour; a cancelled flight costs you the day. Book the 11am–2pm departure so there is still a schedule behind you if it goes wrong, and treat a same-day connection as optimistic. 1,356 completed flights over 12 months sit behind that.
Related
Where to go next
- JFK to SEA, every carrier
- Alaska on SEA to JFK, the return leg
- Delta Air Lines on JFK to SEA73.2%
- JetBlue Airways on JFK to SEA71.3%
- Alaska Airlines network-wide record
- John F. Kennedy International (JFK) delay statistics
- Seattle-Tacoma International (SEA) delay statistics
- The US routes with the most cancellations
- What a cancellation rate actually tells you (and what it hides)
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.