Route reliability record

SMF→LAS

Sacramento to Las Vegas

Flights: 4,238
Period: July 2025 to June 2026
Distance: 397 mi
Carriers: 4

This route lands a B+, 3 points better than the national rate of 77.6%. About one flight in five arrive 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 4,238 flights, of which SkyWest Airlines flew 405 at 90.7% on time.

The US average over the same twelve months is 77.6%, so there is little to separate this route from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.

On time

80.1%

Arrivals under 15 minutes late, of 4,211 completed flights

Avg delay

58 min

Across delayed arrivals only, not all flights

Cancelled

0.59%

National rate is 1.81%

Best carrier

SkyWest

90.7% on time across 405 flights

These figures cover 4,238 flights between July 2025 and June 2026. The median arrival is 5 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 LAS

The choice of carrier is not cosmetic here. SkyWest Airlines arrives on time 90.7% of the time; Southwest Airlines manages 78.7%. Sample sizes sit next to every figure, because a two-point gap across 3,432 flights means less than a ten-point one.

On-time performance by carrier on SMF to LAS
Airline	Flights	On time	Avg delay	Cancelled	Grade
SkyWest Airlines	405	90.7%	90 min	1.48%	A
Spirit Airlinesthin sample	190	86.0%	69 min	2.11%	A
Southwest Airlines	3,432	78.7%	54 min	0.35%	B+
Frontier Airlinesthin sample	211	76.4%	77 min	1.42%	B

The spread between SkyWest and Southwest is 12 points, wide enough that it should decide the booking. On a hundred trips that is 12 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 26 points, against 12 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am693 flights94.4%
8am–11am863 flights91.0%
11am–2pm638 flights76.1%
2pm–5pm950 flights74.7%
5pm–8pm642 flights68.6%
8pm–5am452 flights70.2%

Scale runs 60% to 100%. Rows with fewer than 30 flights show a dash.

Book the early departure. Flights leaving between 5am–8am arrive on time 94.4% of the time, against 68.6% for the evening window. That is 26 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 2pm–5pm window is the busiest, with 950 flights scheduled in it.

Across the year

When delays peak on this route

Twelve months, one bar each, drawn from the same 4,238 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.February best, October worst

Delays peak in October, when the on-time rate falls to 75.1%. February is the strongest month at 86.3%. Moving a flexible trip across that boundary buys 11 points. July was the busiest month here, with 452 flights.

Across the week, Saturday is the strongest day at 87.6% on time and Friday the weakest at 73.2%. 14 points is a smaller lever than departure hour, but it is free.

Delay causes

Why this route gets delayed

One category carries most of the weight here. Late-arriving aircraft accounts for 51% of the 48,000 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.

Late-arriving aircraft
51%
Carrier
24%
National Airspace System
22%
Extreme weather
2%
Security
0%

51% 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 48,000 reported delay minutes here, that single category outweighs weather by 21 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 48,377 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 94.4% on time here.

Cancellations are rare at 0.59%, 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

6.2% 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 are the about an hour kind, which a normal layover absorbs.

At 397 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 78.2% on time across 4,239 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 4,238 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 68.6% on time against 94.4% for the 5am–8am slot, and that 26 points is the largest single thing you control here. SkyWest Airlines is the strongest operator if the fares are close. 4,211 completed flights over 12 months sit behind that.

Common questions

SMF to LAS questions

How often is SMF to LAS delayed?

About one flight in five arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 19.9% of the 4,238 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 LAS?

SkyWest Airlines leads at 90.7% on time across 405 flights. Southwest Airlines is at the other end on 78.7%, a gap of 12 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 LAS?

The 5am–8am departure window is the strongest at 94.4% on time. The 5pm–8pm window is the weakest at 68.6%, 26 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 October delays on SMF to LAS?

October is the weakest month at 75.1% on time, compared with 86.3% in February. Across the year that is 11 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.

Where to go next

Direction matters. SMF to LAS and LAS 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