Route profile
LAX→SEA
Flight reliability, delays and best times to fly from Los Angeles to Seattle. · 954 miles
Right now
Current conditions at both ends of this route.
Aviation weather is not currently a factor. FAA operational data — ground stops, ground delay programs and closures — is not currently available to FlyerIntel.
Aviation weather is not currently a factor. FAA operational data — ground stops, ground delay programs and closures — is not currently available to FlyerIntel.
Airport conditions describe the airfield, not any individual flight. An airport operating normally is not a guarantee that a specific flight will depart on time.
Route reliability
July 2023 – June 2026
Better than 90% of comparable major US routes (4,577 compared)
Calculated from 22,509 flights. How this is calculated
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – June 2026
Best time to fly
On-time arrival rate by scheduled local departure time.
LAX → SEA flights departing 5–9 AM arrived on time 89.0% of the time, against 80.5% for 9 PM–5 AM departures — a gap of 8.5 percentage points.
By departure window
By departure hour
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – June 2026 · Buckets with fewer than 120 flights are not scored.
Airlines on this route
Performance by the carrier that actually operated the flight.
| Carrier | Flights | On time | Cancelled | Median delay | Severe |
|---|---|---|---|---|---|
| Alaska Airlines | 10,185 | 83.4% | 1.25% | -7 min | 3.8% |
| Delta Air Lines | 6,648 | 88.0% | 0.42% | -15 min | 4.1% |
| SkyWest Airlines | 2,988 | 84.7% | 0.37% | -9 min | 4.7% |
| United Airlines | 1,720 | 84.8% | 0.64% | -8 min | 4.4% |
| Frontier Airlines | 443 | 81.4% | 2.71% | -10 min | 6.0% |
| Spirit Airlines | 274 | 85.7% | 0.36% | -15 min | 6.6% |
| JetBlue | 240 | 76.1% | 0.83% | -5 min | 7.1% |
Delta Air Lines arrived on time 12.0 percentage points more often than JetBlue on this route.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – June 2026 · Carriers with fewer than 200 flights on this route are not listed.
Other ways to fly Los Angeles to Seattle
Airport pairs serving the same journey, grouped by the DOT's own city-market definition. They do not perform the same way.
ONT → SEA is the most reliable pairing for this journey at 86.5% on time, against 81.4% for BUR → SEA.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – June 2026 · Grouped by DOT city market, which places Newark with the New York airports and Baltimore with the Washington ones.
Individual flights on this route
The same route is not equally reliable at every hour. These are the flight numbers with enough operating history to judge separately.
| Flight | Scheduled | Operations | On time |
|---|---|---|---|
| AS1301 Alaska Airlines | 5:40 PM | 979 | 82.6% |
| DL1714 Delta Air Lines | 9:35 AM | 949 | 93.3% |
| DL1045 Delta Air Lines | 11:45 AM | 891 | 87.4% |
| DL1551 Delta Air Lines | 7:59 PM | 768 | 82.0% |
| DL2606 Delta Air Lines | 2:00 PM | 754 | 87.4% |
| DL2640 Delta Air Lines | 5:15 PM | 719 | 84.1% |
| AS1305 Alaska Airlines | 6:55 PM | 667 | 74.7% |
| AS1317 Alaska Airlines | 10:00 AM | 644 | 82.2% |
| DL2980 Delta Air Lines | 7:00 AM | 573 | 92.9% |
| F91177 Frontier Airlines | 3:15 PM | 417 | 80.7% |
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – June 2026 · Flight numbers with fewer than 270 operations on this route, or no longer scheduled, are not listed.
Weekly and seasonal patterns
By day of week
Tuesday is historically the most reliable day and Sunday the least, a gap of 7.2 percentage points.
By month
June is historically the weakest month and November the strongest, a spread of 11.0 percentage points.
Historical trend
On-time arrival rate by month.
Over the most recent 12 months (2025-07 to 2026-06), on-time arrivals averaged 85.4% against 84.5% in the 12 months before — broadly unchanged.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – June 2026
Data and methodology
All figures on this page are calculated by FlyerIntel from 22,509 LAX → SEA flight records published by the US DOT Bureau of Transportation Statistics, covering July 2023 – June 2026. A flight is counted as delayed when it arrives 15 or more minutes after its scheduled arrival time, following BTS methodology. Cancelled and diverted flights have no arrival time and are excluded from on-time rates rather than counted as late.