Carrier route record
OOLAX→SEA
SkyWest Airlines · Los Angeles to Seattle
- Flights
- 1,239
- Period
- July 2025 to June 2026
- Share of route
- 17%
- Carriers
- 6
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with SkyWest Airlines.
SkyWest on LAX to SEA earns a B+. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 7 points better than the national rate of 77.6%. When something does go wrong the average delay runs an hour and a half. That rests on 1,239 flights. The strongest carrier on the route with a full sample, Delta Air Lines, flew 2,224 at 86.8% on time.
Delta Air Lines is the most reliable of the three carriers covered here at 86.8% on time across 2,224 flights.
Key figures
On time
84.6%
Arrivals under 15 minutes late, of 1,228 completed flights
Avg delay
82 min
Across delayed arrivals only, not all flights
Cancelled
0.65%
National rate is 1.81%
Whole route
85.4%
Every carrier on LAX to SEA, 7,424 flights
These figures cover 1,239 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
SkyWest against every carrier on LAX to SEA
SkyWest flew 1,239 of the 7,424 flights on LAX to SEA, about 17% of it. Its 84.6% on time is about level with the route as a whole at 85.4%. Ranked by on-time rate it is number four of six carriers on the route, where the range runs from Delta at 86.8% to Frontier at 79.7%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The three carriers here are closely matched: 2 points separate the best from the worst. At that spread, schedule and price are better tie-breakers than reliability. Sample sizes are shown so you can see which rows are worth weighing.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines | 2,224 | 86.8% | 76 min | 0.76% | A+ |
| Alaska Airlines | 3,279 | 85.2% | 49 min | 1.10% | A |
| United Airlines | 395 | 85.0% | 47 min | 0.51% | A+ |
| SkyWest Airlines (this page) | 1,239 | 84.6% | 82 min | 0.65% | B+ |
| American Airlinesthin sample | 11 | 81.8% | 159 min | 0.00% | B+ |
| Frontier Airlinesthin sample | 276 | 79.7% | 76 min | 3.62% | B− |
No carrier stands out. Delta tops the table at 86.8%, 2 points clear of the bottom, which is inside the range this kind of sample moves year to year.
Departure window
When SkyWest runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 14 points, against 2 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am—
- 8am–11am158 flights91.8%
- 11am–2pm346 flights90.9%
- 2pm–5pm230 flights78.3%
- 5pm–8pm381 flights78.1%
- 8pm–5am124 flights89.5%
Scale runs 70% to 95%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 91.8% of the time, against 78.1% for the evening window. That is 14 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5pm–8pm window is the busiest, with 381 flights scheduled in it.
Across the year
SkyWest on LAX to SEA through the year
December is the weak month at 74.6% on time, against 91.4% in November. 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. March was the busiest month here, with 169 flights.
Across the week, Tuesday is the strongest day at 91.0% on time and Thursday the weakest at 80.8%. 10 points is a smaller lever than departure hour, but it is free.
Delay causes
Why SkyWest runs late on this route
One category carries most of the weight here. Carrier accounts for 62% 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.
- 62%Carrier
- 27%Late-arriving aircraft
- 8%National Airspace System
- 3%Extreme weather
The largest share of delay minutes, 62%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 9,709 of the 16,000 delay minutes reported here. The split is drawn from 15,561 reported delay minutes.
Cancellations are rare at 0.65%, below the national 1.81% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.
Connections and stage length
What a delay here 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 an hour and a half, which a normal layover absorbs.
The 954 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 runs 86.3% on time across 1,241 flights, within 2 points of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
The sample behind these figures is 1,239 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 SkyWest on LAX to SEA
Put together: the calendar is the biggest lever here, not the carrier or the hour. November runs 91.4% on time and December 74.6%, a swing of 17 points. If the dates move at all, move them out of December before you think about anything else. 1,228 completed flights over 12 months sit behind that.
Related
Where to go next
- LAX to SEA, every carrier
- SkyWest on SEA to LAX, the return leg
- Delta Air Lines on LAX to SEA86.8%
- Alaska Airlines on LAX to SEA85.2%
- United Airlines on LAX to SEA85.0%
- Frontier Airlines on LAX to SEA79.7%
- SkyWest Airlines network-wide record
- Los Angeles International (LAX) delay statistics
- Seattle-Tacoma International (SEA) delay statistics
- The best time of day to fly, according to 7.04 million flight records
- Worst months to fly in the US, ranked by the data
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.