Route reliability record

SMF→LAX

Sacramento to Los Angeles

Flights: 5,637
Period: July 2025 to June 2026
Distance: 373 mi
Carriers: 5

This route earns a A+. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 8 points better than the national rate of 77.6%. When something does go wrong the average delay runs about an hour. That rests on 5,637 flights, of which SkyWest Airlines flew 3,517 at 90.1% on time.

Set against the rest of the country, this route's record is 8 points better than the US average of 77.6%. That gap is worth roughly 84 fewer late arrivals for every thousand flights.

On time

86.0%

Arrivals under 15 minutes late, of 5,611 completed flights

Avg delay

66 min

Across delayed arrivals only, not all flights

Cancelled

0.44%

National rate is 1.81%

Best carrier

SkyWest

90.1% on time across 3,517 flights

These figures cover 5,637 flights between July 2025 and June 2026. The median arrival is 9 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

Which airline is most reliable on SMF to LAX

The choice of carrier is not cosmetic here. SkyWest Airlines arrives on time 90.1% of the time; Southwest Airlines manages 77.3%. Sample sizes sit next to every figure, because a two-point gap across 1,616 flights means less than a ten-point one.

On-time performance by carrier on SMF to LAX
Airline	Flights	On time	Avg delay	Cancelled	Grade
Delta Air Linesthin sample	99	95.9%	24 min	1.01%	A
United Airlinesthin sample	201	91.5%	72 min	0.00%	A+
SkyWest Airlines	3,517	90.1%	86 min	0.45%	A+
Southwest Airlines	1,616	77.3%	48 min	0.19%	B+
Frontier Airlinesthin sample	204	73.9%	60 min	2.45%	C

The spread between SkyWest and Southwest is 13 points, wide enough that it should decide the booking. On a hundred trips that is 13 more arrivals inside the on-time window.

Departure window

The best time of day to leave

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 13 points, against 13 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am1,378 flights91.6%
8am–11am921 flights90.2%
11am–2pm800 flights87.6%
2pm–5pm864 flights84.1%
5pm–8pm1,121 flights78.9%
8pm–5am553 flights79.9%

Scale runs 70% to 95%. Rows with fewer than 30 flights show a dash.

Book the early departure. Flights leaving between 5am–8am arrive on time 91.6% of the time, against 78.9% for the evening window. That is 13 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5am–8am window is the busiest, with 1,378 flights scheduled in it.

Across the year

When delays peak on this route

Twelve months, one bar each, drawn from the same 5,637 flights. The strip shows how much of this route's record is set by the calendar rather than by the operation.

Darker means more delays. Figures are on-time percentages.September best, March worst

The year is unusually even here, with only 5 points between the best and worst months. March is the softest at 83.7%, but the seasonal effect is small enough that it should not drive when you travel. May was the busiest month here, with 525 flights.

Across the week, Wednesday is the strongest day at 91.6% on time and Sunday the weakest at 81.2%. 10 points is a smaller lever than departure hour, but it is free.

Delay causes

Why this route gets delayed

Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 52,000 reported delay minutes.

Late-arriving aircraft
42%
Carrier
39%
Extreme weather
12%
National Airspace System
7%
Security
0%

Extreme weather accounts for 12% 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 1.9 times the usual weather exposure. The split is drawn from 51,849 reported delay minutes.

42% 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 52,000 reported delay minutes here, that single category outweighs weather by 4 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.

Cancellations are rare at 0.44%, 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 actually costs

Badly late arrivals are rare here: only 4.1% 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.

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 84.6% on time across 5,634 flights, within about a point 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 5,637 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 this route

Put together: avoid the 5pm–8pm departure. It runs 78.9% on time against 91.6% for the 5am–8am slot, and that 13 points is the largest single thing you control here. SkyWest Airlines is the strongest operator if the fares are close. 5,611 completed flights over 12 months sit behind that.

Common questions

SMF to LAX questions

How often is SMF to LAX delayed?

About one flight in seven arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 14.0% of the 5,637 flights in this analysis, against 22.4% nationally. Delayed flights are late by about an hour on average.

Which airline is most reliable on SMF to LAX?

SkyWest Airlines leads at 90.1% on time across 3,517 flights. Southwest Airlines is at the other end on 77.3%, a gap of 13 points. Sample size matters as much as the percentage: a rate built from a few hundred flights moves around far more than one built from ten thousand.

What time of day has the fewest delays on SMF to LAX?

The 5am–8am departure window is the strongest at 91.6% on time. The 5pm–8pm window is the weakest at 78.9%, 13 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.

How bad are March delays on SMF to LAX?

March is the weakest month at 83.7% on time, compared with 88.2% in September. Across the year that is 5 points between the best and worst months. The seasonal swing is modest enough that it should not decide when you travel.

Where to go next

Direction matters. SMF to LAX and LAX to SMF are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.

Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Updated monthly. How this data is collected.

Key figures