75% of flights from Seattle to New York arrived on time over the past 12 months. That is worse than the typical U.S. route. The 11 p.m. departures ran on time 85% of the time; the 2 p.m. ones 62%. Most reliable airline: Delta Air Lines (76%). 11% 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 → JFK: when a flight was late, it was under 45 minutes late 62% of the time. About 1 in 16 flights landed an hour or more late, and 1 in 88 three hours or more; 3.2% were cancelled outright.
- On time or early75%
- 15–30 min late8.6%
- 30–60 min late6.1%
- 1–2 hours late3.6%
- 2–3 hours late1.5%
- 3+ hours late1.1%
- Diverted1.1%
- Cancelled3.2%
Share of all 2,906 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 | 1,402 | 75% | 2.6% | −7 min | 5.6% | +53 min | Alaska Airlines |
| Delta Air Lines | 1,338 | 76% | 3.2% | −7 min | 6.1% | +70 min | Delta Air Lines |
| JetBlue | 166 | 64% | 7.8% | −2 min | 12.7% | +170 min | JetBlue |
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 |
|---|---|---|
| 7 a.m. | 85% | 83% |
| 9 a.m. | 71% | — |
| 10 a.m. | 80% | — |
| 11 a.m. | 63% | 65% |
| 2 p.m. | 60% | — |
| 4 p.m. | — | 65% |
| 9 p.m. | — | 85% |
| 10 p.m. | 79% | 79% |
| 11 p.m. | 87% | — |
Last flight of the day
On SEA → JFK, each airline's last flight of the day was cancelled 2.3% of the time, against 3.1% for its earlier flights, so here the last flight is actually the safer one. It arrived 3+ hours late 0.0% of the time (earlier flights: 1.3%). It matters more than the numbers suggest. Miss an earlier flight and there's another one that evening; miss the last one and you're usually waiting until morning.
| Airline | Last departure | Last: cancelled | Last: 3h+ late | Earlier: cancelled | Next morning |
|---|---|---|---|---|---|
| Alaska Airlines | 11:15 p.m. | 1.1% | 0.0% | 3.2% | first flight 7:00 a.m. |
| Delta Air Lines | 10:40 p.m. | 3.6% | 0.0% | 3.1% | first flight 7:15 a.m. |
Last flight = the airline's last scheduled departure on this route that day, on days it flies the route at least twice; past 12 months. Times are typical scheduled times over the latest three months.
By month
Each calendar month pooled over 2023–2026. Best: November (86%). Worst: July (58%).
By day of week
| Day | Flights | On time | Cancelled |
|---|---|---|---|
| Monday | 423 | 74% | 2.8% |
| Tuesday | 411 | 79% | 2.7% |
| Wednesday | 416 | 80% | 0.7% |
| Thursday | 412 | 72% | 1.9% |
| Friday | 417 | 73% | 3.8% |
| Saturday | 410 | 76% | 4.4% |
| Sunday | 417 | 70% | 6.0% |
Why flights were late
Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.
Cancellations: weather 53 · airline 27 · air traffic/airport 13
Month by month
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 26 | 7:00 a.m. | 363 | 82% | 3.9% | −11 min | Alaska Airlines |
| DL 429 | 7:15 a.m. | 365 | 83% | 4.1% | −10 min | Delta Air Lines |
| AS 34 | 9:29 a.m. | 364 | 74% | 3.3% | −6 min | Alaska Airlines |
| DL 415 | 1:45 p.m. | 363 | 68% | 2.8% | −2 min | Delta Air Lines |
| AS 16 | 2:02 p.m. | 329 | 61% | 2.7% | −2 min | Alaska Airlines |
| DL 452 | 10:40 p.m. | 361 | 81% | 3.6% | −9 min | Delta Air Lines |
| AS 22 | 11:15 p.m. | 315 | 83% | 0.6% | −9 min | Alaska Airlines |
| B6 264 | 11:59 p.m. | 166 | 64% | 7.8% | −2 min | JetBlue |
Worst days in the past year
| Date | Flights | On time | Cancelled |
|---|---|---|---|
| Feb 22, 2026 | 7 | 0% | 7 |
| Jan 25, 2026 | 6 | 0% | 6 |
| Feb 23, 2026 | 6 | 0% | 6 |
| Jul 18, 2026 | 9 | 11% | 6 |
| Dec 14, 2025 | 8 | 13% | 3 |
Nearby airport alternatives
Other ways to make the same trip, using airports within 60 miles of Seattle or New York. SEA → EWR has been 6 points more reliable.
| Route | Flights | On time | Cancelled |
|---|---|---|---|
| SEA → JFK (this route) | 2,906 | 75% | 3.2% |
| SEA → EWR Seattle-Tacoma to Newark | 2,264 | 81% | 2.1% |
Questions
How often are flights from SEA to JFK on time?
75% of 2,906 scheduled flights from Seattle, WA to New York, NY arrived within 15 minutes of schedule between September 2025 and August 2026. 3.2% were cancelled.
What is the best time of day to fly SEA to JFK?
Flights scheduled to leave at 11 p.m. were the most reliable (85% on time). The 2 p.m. departures were the least (62%).
Which airline is most on time from SEA to JFK?
Delta Air Lines: 76% of its 1,338 flights on the route arrived on time. Alaska Airlines: 75%. JetBlue: 64%.
What month has the most delays from SEA to JFK?
July (58% on time). The best month is November (86%), over 2023–2026.
Is the last flight of the day from SEA to JFK more likely to be cancelled?
No, the opposite. Each airline's last SEA–JFK flight of the day was cancelled 2.3% of the time over the past year, against 3.1% for its earlier flights. If the last flight is cancelled, the next one is usually the following morning.
Related
- JFK → SEA (return)
- Seattle-Tacoma (SEA) delays by hour
- Flights into New York JFK (JFK)
- Alaska Airlines on-time record
- Delta Air Lines on-time record
- JetBlue 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.