Route reliability record
LAX→SFO
Los Angeles to San Francisco
- Flights
- 10,832
- Period
- June 2025 to May 2026
- Distance
- 337 mi
- Carriers
- 7
This route draws a C+. About one flight in three arrive at least 15 minutes late, and the typical late arrival is about an hour behind schedule. Build slack into anything you connect to. That rests on 10,832 flights, of which SkyWest Airlines flew 2,614 at 75.1% on time.
SkyWest Airlines is the most reliable of the seven carriers covered here at 75.1% on time across 2,614 flights.
Key figures
On time
67.8%
Arrivals under 15 minutes late, of 10,742 completed flights
Avg delay
58 min
Across delayed arrivals only, not all flights
Cancelled
0.80%
National rate is 1.80%
Best carrier
SkyWest
75.1% on time across 2,614 flights
These figures cover 11,000 flights between June 2025 and May 2026. Beyond the headline rate, 10.5% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Carrier by carrier
Which airline is most reliable on LAX to SFO
The choice of carrier is not cosmetic here. SkyWest Airlines arrives on time 75.1% of the time; Alaska Airlines manages 53.2%. Sample sizes sit next to every figure, because a two-point gap across 507 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SkyWest Airlines | 2,614 | 75.1% | 61 min | 1.11% | B |
| United Airlines | 3,250 | 68.7% | 56 min | 0.22% | C+ |
| Delta Air Lines | 2,375 | 67.6% | 54 min | 1.52% | C |
| American Airlines | 374 | 62.9% | 71 min | 0.27% | D+ |
| Southwest Airlines | 1,325 | 62.6% | 60 min | 0.30% | D+ |
| Frontier Airlines | 387 | 53.7% | 75 min | 1.81% | F |
| Alaska Airlines | 507 | 53.2% | 52 min | 0.59% | F+ |
The spread between SkyWest and Alaska is 22 points, wide enough that it should decide the booking. On a hundred trips that is 22 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 32 points, against 22 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am1,444 flights91.5%
- 8am–11am2,056 flights59.1%
- 11am–2pm1,682 flights70.1%
- 2pm–5pm1,442 flights68.5%
- 5pm–8pm2,319 flights64.5%
- 8pm–5am1,889 flights60.7%
Scale runs 50% to 95%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 91.5% of the time, against 59.1% for the morning window. That is 32 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on.
Across the year
When delays peak on this route
This route's year swings by 41 points from best month to worst, which is wide. An annual average tells you very little about the week you are actually flying, so read the strip rather than the headline if your dates are fixed.
Delays peak in May, when the on-time rate falls to 44.1%. March is the strongest month at 85.2%. Moving a flexible trip across that boundary buys 41 points.
Across the week, Saturday is the strongest day at 73.8% on time and Sunday the weakest at 63.5%. 10 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. National Airspace System accounts for 50% of the 202,000 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.
- 50%National Airspace System
- 27%Late-arriving aircraft
- 22%Carrier
- 1%Extreme weather
- 0%Security
50% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 101,000 minutes out of 202,000, against a national NAS share of 21%.
Cancellations are rare at 0.80%, below the national 1.80% 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
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 10.5% of arrivals land a full hour or more behind schedule, against 8.2% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.
At 337 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 is a different operation and performs like one: it runs 75.8% on time across 10,834 flights, 8 points above this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 8 points of difference.
The sample behind these figures is 10,832 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: the calendar is the biggest lever here, not the carrier or the hour. March runs 85.2% on time and May 44.1%, a swing of 41 points. If the dates move at all, move them out of May before you think about anything else.
Common questions
LAX to SFO questions
How often is LAX to SFO delayed?
About one flight in three arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 32.2% of the 10,832 flights in this analysis, against 22.6% nationally. Delayed flights are late by about an hour on average.
Which airline is most reliable on LAX to SFO?
SkyWest Airlines leads at 75.1% on time across 2,614 flights. Alaska Airlines is at the other end on 53.2%, a gap of 22 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 LAX to SFO?
The 5am–8am departure window is the strongest at 91.5% on time. The 8am–11am window is the weakest at 59.1%, 32 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 May delays on LAX to SFO?
May is the weakest month at 44.1% on time, compared with 85.2% in March. Across the year that is 41 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
- SFO to LAX — the return legseparate record
- Los Angeles International (LAX) delay statistics
- San Francisco International (SFO) delay statistics
- SkyWest Airlines on-time record75.1%
- United Airlines on-time record68.7%
- Delta Air Lines on-time record67.6%
- The best time of day to fly, according to 7.05 million flight records
- Connecting flights: how much buffer the data says you need
Direction matters. LAX to SFO and SFO to LAX 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, June 2025 to May 2026. Updated monthly. How this data is collected.