Carrier route record
WNLAX→SMF
Southwest Airlines · Los Angeles to Sacramento
- Flights
- 1,614
- Period
- July 2025 to June 2026
- Share of route
- 29%
- Carriers
- 5
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Southwest Airlines.
Southwest on LAX to SMF lands a B+, about a point better than the national rate of 77.6%. About one flight in five arrives 15 minutes late or worse, and those flights are late by roughly 55 minutes on average. That is a workable record, not a spotless one. That rests on 1,614 flights, with a median arrival 7 minutes early.
The US average over the same twelve months is 77.6%, so there is little to separate Southwest on LAX to SMF from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
79.0%
Arrivals under 15 minutes late, of 1,609 completed flights
Avg delay
53 min
Across delayed arrivals only, not all flights
Cancelled
0.19%
National rate is 1.81%
Whole route
84.6%
Every carrier on LAX to SMF, 5,634 flights
These figures cover 1,614 flights between July 2025 and June 2026. The median arrival is 7 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
Southwest against every carrier on LAX to SMF
Southwest flew 1,614 of the 5,634 flights on LAX to SMF, about 29% of it. Its 79.0% on time is 6 points worse than the route as a whole, which runs 84.6%. Ranked by on-time rate it is number four of five carriers on the route, where the range runs from SkyWest at 87.8% to Delta at 67.0%. Three of those carriers flew fewer than 365 flights here, so treat their positions as rough.
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SkyWest Airlines | 3,517 | 87.8% | 74 min | 0.43% | A+ |
| Frontier Airlinesthin sample | 204 | 83.5% | 56 min | 1.96% | B |
| United Airlinesthin sample | 201 | 83.5% | 42 min | 0.00% | B+ |
| Southwest Airlines (this page) | 1,614 | 79.0% | 53 min | 0.19% | B+ |
| Delta Air Linesthin sample | 98 | 67.0% | 66 min | 1.02% | C |
Departure window
When Southwest runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 41 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am302 flights94.7%
- 8am–11am272 flights89.7%
- 11am–2pm292 flights83.5%
- 2pm–5pm186 flights77.4%
- 5pm–8pm289 flights72.6%
- 8pm–5am273 flights54.0%
Scale runs 45% to 100%. Rows with fewer than 30 flights show a dash.
The 8pm–5am window is where this operation falls apart: 54.0% on time, against 94.7% for the 5am–8am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 5am–8am window is the busiest, with 302 flights scheduled in it.
Across the year
Southwest on LAX to SMF through the year
Delays peak in May, when the on-time rate falls to 67.9%. January is the strongest month at 89.3%. Moving a flexible trip across that boundary buys 21 points. June was the busiest month here, with 152 flights.
Across the week, Tuesday is the strongest day at 87.3% on time and Monday the weakest at 71.6%. 16 points is a smaller lever than departure hour, but it is free.
Delay causes
Why Southwest runs late on this route
One category carries most of the weight here. Late-arriving aircraft accounts for 68% of the 18,000 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.
- 68%Late-arriving aircraft
- 29%Carrier
- 3%National Airspace System
68% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 18,000 reported delay minutes here, that single category outweighs weather by 68 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 17,909 reported delay minutes.
The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 94.7% on time here.
Cancellations are rare at 0.19%, 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 roughly 55 minutes, which a normal layover absorbs.
At 373 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 5am–8am window matters as much as it does.
The return leg runs 77.3% on time across 1,616 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 1,614 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 Southwest on LAX to SMF
Put together: the calendar is the biggest lever here, not the carrier or the hour. January runs 89.3% on time and May 67.9%, a swing of 21 points. If the dates move at all, move them out of May before you think about anything else. 1,609 completed flights over 12 months sit behind that.
Related
Where to go next
- LAX to SMF, every carrier
- Southwest on SMF to LAX, the return leg
- SkyWest Airlines on LAX to SMF87.8%
- Frontier Airlines on LAX to SMF83.5%
- United Airlines on LAX to SMF83.5%
- Southwest Airlines network-wide record
- Los Angeles International (LAX) delay statistics
- Sacramento International (SMF) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
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.