Carrier route record
OOSMF→SEA
SkyWest Airlines · Sacramento to Seattle
- Flights
- 1,952
- Period
- July 2025 to June 2026
- Share of route
- 44%
- Carriers
- 3
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with SkyWest Airlines.
SkyWest on SMF to SEA earns an A+. Close to nine flights in ten arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 10 points better than the national rate of 77.6%. When something does go wrong the average delay runs about an hour. That rests on 1,952 flights. The strongest carrier on the route with a full sample, Alaska Airlines, flew 1,309 at 80.3% on time.
Set against the rest of the country, SkyWest's SMF to SEA record is 10 points better than the US average of 77.6%. That gap is worth roughly 98 fewer late arrivals for every thousand flights.
Key figures
On time
87.4%
Arrivals under 15 minutes late, of 1,943 completed flights
Avg delay
57 min
Across delayed arrivals only, not all flights
Cancelled
0.26%
National rate is 1.81%
Whole route
82.7%
Every carrier on SMF to SEA, 4,416 flights
These figures cover 1,952 flights between July 2025 and June 2026. The median arrival is 12 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 SMF to SEA
SkyWest flew 1,952 of the 4,416 flights on SMF to SEA, about 44% of it. Its 87.4% on time is 5 points better than the route as a whole, which runs 82.7%. Ranked by on-time rate it is first of three carriers on the route, where the range runs from SkyWest at 87.4% to Southwest at 77.4%.
The two carriers here are closely matched: 3 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 |
|---|---|---|---|---|---|
| SkyWest Airlines (this page) | 1,952 | 87.4% | 57 min | 0.26% | A+ |
| Alaska Airlines | 1,309 | 80.3% | 42 min | 0.61% | B+ |
| Southwest Airlines | 1,155 | 77.4% | 43 min | 0.17% | B+ |
No carrier stands out. Alaska tops the table at 80.3%, 3 points clear of the bottom, which is inside the range this kind of sample moves year to year.
Flight by flight
SkyWest flight numbers on SMF to SEA
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 24 points, against 3 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am341 flights90.9%
- 8am–11am63 flights82.5%
- 11am–2pm652 flights92.4%
- 2pm–5pm214 flights89.7%
- 5pm–8pm518 flights84.3%
- 8pm–5am164 flights68.3%
Scale runs 60% to 100%. Rows with fewer than 30 flights show a dash.
The best window here is not the first bank but the 11am–2pm slot at 92.4% on time, ahead of 8pm–5am at 68.3%. Where the curve peaks mid-day rather than at dawn, the constraint is usually congestion at one end rather than the aircraft's own rotation. The 11am–2pm window is the busiest, with 652 flights scheduled in it.
Across the year
SkyWest on SMF to SEA through the year
August is the worst month at 83.2% on time, 10 points below February, the best at 93.0%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. July was the busiest month here, with 208 flights.
The day of the week is close to irrelevant here: 4 points separates the best day from the worst. Weekly demand peaks are not what drives the delays on this operation.
Delay causes
Why SkyWest runs late on this route
One category carries most of the weight here. Carrier accounts for 54% of the 14,000 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.
- 54%Carrier
- 19%Extreme weather
- 14%Late-arriving aircraft
- 12%National Airspace System
- 1%Security
Extreme weather accounts for 19% of delay minutes, well above the single-digit share typical across the system. Weather delays are lumpy: they arrive as whole bad days rather than as a steady drag, so the monthly strip above is the more useful view of the risk. The national share is 6%, so this operation carries roughly 3.0 times the usual weather exposure. The split is drawn from 13,977 reported delay minutes.
The largest share of delay minutes, 54%, 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 7,527 of the 14,000 delay minutes reported here.
Cancellations are rare at 0.26%, 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
Badly late arrivals are rare here: only 3.4% land an hour or more behind schedule, against 8.1% nationally. Connections built on this flight are about as safe as US domestic connections get, though a cancelled flight still ignores every layover you give it.
The 605 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 89.3% on time across 1,941 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 1,952 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 SMF to SEA
Put together: avoid the 8pm–5am departure. It runs 68.3% on time against 92.4% for the 11am–2pm slot, and that 24 points is the largest single thing you control here. Alaska Airlines is the strongest operator if the fares are close. 1,943 completed flights over 12 months sit behind that.
Related
Where to go next
- SMF to SEA, every carrier
- SkyWest on SEA to SMF, the return leg
- Alaska Airlines on SMF to SEA80.3%
- Southwest Airlines on SMF to SEA77.4%
- SkyWest Airlines network-wide record
- Sacramento International (SMF) 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.