Airports › Seattle (SEA) › May 2025
Airport month · May 2025
Seattle/Tacoma International in May 2025
BTS: A flight is counted as on time if it arrived less than 15 minutes after its scheduled time. Only carriers with at least 0.5 percent of domestic scheduled passenger revenue report.
In May 2025, reporting carriers scheduled 14,630 domestic departures from Seattle/Tacoma International (SEA). 80.2% left less than 15 minutes late and 76.3% reached their destination on time; 0.4% were cancelled.
Nationally that month, 76.7% of flights departed on time and 75.4% arrived on time, so SEA departures were 3.5 points above the national departure figure.
A year earlier, in May 2024, the airport had 14,338 departures with 76.6% leaving on time: a change of +3.6 points, with flights up 2%.
Flights arriving at SEA that month were on time 78.4% of the time (14,625 scheduled arrivals).
Of the delay minutes that carriers assigned to a BTS cause category that month, air carrier 37%, national aviation system 32% and late-arriving aircraft 30%.
- On time 76.3%
- Arrived 15+ minutes late 23.2%
- Cancelled 0.4%
- Diverted 0.2%
May 2025 against a year earlier, the airport's year and the nation
| Measure | May 2025 | May 2024 | SEA, 12 months to Jul 2026 | All reported flights, May 2025 |
|---|---|---|---|---|
| Departed on time | 80.2% | 76.6% | 78.2% | 76.7% |
| Arrived on time | 76.3% | 76.2% | 78.6% | 75.4% |
| Cancelled | 0.4% | 0.5% | 0.9% | 1.0% |
| Average departure delay (late minutes only) | 11.0 min | 13.3 min | 13.2 min | 17.5 min |
| Scheduled departures a day | 488 | 478 | 452 | 20,188 |
| Scheduled departures | 14,630 | 14,338 | 164,821 | 605,648 |
Airlines that month
| Reporting carrier | Flights | Share | On time | Avg arrival delay | Cancelled |
|---|---|---|---|---|---|
| AS Alaska Airlines | 6,942 | 47% | 68.7% | 10.5 min | 0.5% |
| DL Delta Air Lines | 2,752 | 19% | 83.1% | -0.1 min | 0.1% |
| OO SkyWest Airlines | 2,612 | 18% | 86.8% | -1.6 min | 0.0% |
| UA United Airlines | 780 | 5% | 81.9% | 2.6 min | 0.6% |
| WN Southwest Airlines | 593 | 4% | 77.7% | 6.5 min | 0.3% |
| AA American Airlines | 516 | 4% | 80.6% | 3.3 min | 1.2% |
| F9 Frontier Airlines | 156 | 1% | 75.6% | 15.8 min | 1.3% |
| HA Hawaiian Airlines | 155 | 1% | 69.0% | 12.3 min | 0.0% |
| B6 JetBlue Airways | 62 | 0% | 64.5% | 16.3 min | 1.6% |
| NK Spirit Airlines | 62 | 0% | 85.5% | -2.4 min | 0.0% |
Busiest routes that month
| Route | Cities | Flights | On time | Avg arrival delay | Cancelled |
|---|---|---|---|---|---|
| SEA–ANC | Seattle to Anchorage | 666 | 73.3% | 7.1 min | 0.8% |
| SEA–LAX | Seattle to Los Angeles | 654 | 83.2% | 0.0 min | 0.5% |
| SEA–PHX | Seattle to Phoenix | 650 | 80.6% | 2.1 min | 0.0% |
| SEA–SFO | Seattle to San Francisco | 636 | 76.6% | 5.0 min | 0.5% |
| SEA–DEN | Seattle to Denver | 564 | 66.5% | 16.2 min | 0.4% |
| SEA–LAS | Seattle to Las Vegas | 563 | 78.0% | 6.0 min | 0.2% |
| SEA–ORD | Seattle to Chicago | 536 | 79.3% | 4.2 min | 0.4% |
| SEA–DFW | Seattle to Dallas/Fort Worth | 472 | 75.0% | 7.9 min | 1.5% |
| SEA–GEG | Seattle to Spokane | 453 | 75.9% | 7.0 min | 0.2% |
| SEA–SAN | Seattle to San Diego | 412 | 76.9% | 3.7 min | 0.2% |
| SEA–PDX | Seattle to Portland | 387 | 81.4% | 1.7 min | 0.3% |
| SEA–SJC | Seattle to San Jose | 387 | 80.9% | 3.6 min | 0.5% |
By scheduled departure hour
Delay causes
Questions and answers
How many flights left SEA on time in May 2025?
80.2% of 14,630 scheduled domestic departures left less than 15 minutes late, and 76.3% reached their destination on time. The national figures that month were 76.7% and 75.4%.
How does that compare with a year earlier?
In May 2024, 76.6% of 14,338 departures left on time and 0.5% were cancelled, against 80.2% and 0.4% in May 2025.
Provenance
Source: Bureau of Transportation Statistics, Reporting Carrier On-Time Performance, file for May 2025; public domain. Domestic scheduled flights by reporting carriers, totals and averages only. The site's data runs through July 2026. Full record for SEA · methodology · corrections.