ON TIMEBOARD

STL → LAX on time

St. Louis Lambert (St. Louis, MO) to Los Angeles LAX (Los Angeles, CA). Every scheduled flight, September 2025 to August 2026.

On time
72%
arrived < 15 min late
Cancelled
0.4%
1,028 flights
Typical arrival
+2 min
median vs schedule
When late
+58 min
average delay
Flights / day
3
2 airlines

72% of flights from St. Louis to Los Angeles arrived on time over the past 12 months. That is worse than the typical U.S. route. The 8 a.m. departures ran on time 87% of the time; the 9 p.m. ones 41%. Most reliable airline: American Airlines (74%). 7% of flights arrived more than an hour late or not at all.

How late?

The on-time rate treats a flight 20 minutes late the same as one 5 hours late. Here's the split for STL → LAX: when a flight was late, it was under 45 minutes late 66% of the time. About 1 in 15 flights landed an hour or more late, and 1 in 147 three hours or more; 0.4% were cancelled outright.

Share of all 1,028 scheduled flights, past 12 months, by arrival time against schedule.

By airline

AirlineFlightsOn timeCancelledTypical arrival1h+ lateAvg when lateOperated by
Southwest Airlines67471%0.1%+3 min7.3%+48 minSouthwest Airlines
American Airlines35474%0.9%0 min5.6%+80 minSkyWest

Airline = the name on the ticket. Regional flights (e.g. "Delta Connection") count under the ticketing airline, and the operator is listed.

Best time of day to fly

On-time rate by scheduled departure hour (local time at STL). Delays build through the day as late planes knock on, so early flights usually do best.

30%65%100%6 a.m. departures: 77% on time (328 flights)776a7 a.m. departures: too few flights (77 flights)7a8 a.m. departures: 87% on time (165 flights)878a9 a.m. departures: too few flights (31 flights)9a10 a.m. departures: too few flights (74 flights)10a11 a.m. departures: too few flights (8 flights)11anoon departures: too few flights12p1 p.m. departures: too few flights (10 flights)1p2 p.m. departures: too few flights (40 flights)2p3 p.m. departures: too few flights (14 flights)3p4 p.m. departures: too few flights4p5 p.m. departures: too few flights5p6 p.m. departures: too few flights (51 flights)6p7 p.m. departures: too few flights (26 flights)7p8 p.m. departures: too few flights (44 flights)8p9 p.m. departures: 41% on time (124 flights)419p
STL → LAX, share of flights arriving on time, by departure hour. Hours with under 100 flights are greyed out.
82%+ on time76–82%68–76%under 68%too few flights

By airline and hour

DepartsSouthwest AirlinesAmerican Airlines
6 a.m.—73%
8 a.m.87%—
9 p.m.41%—

Last flight of the day

On STL → LAX, each airline's last flight of the day was cancelled 0.0% of the time, against 0.3% for its earlier flights, so here the last flight is actually the safer one. It arrived 3+ hours late 0.4% of the time (earlier flights: 0.0%). It matters more than the numbers suggest. Miss an earlier flight and there's another one that evening; miss the last one and you're usually waiting until morning.

AirlineLast departureLast: cancelledLast: 3h+ lateEarlier: cancelledNext morning
Southwest Airlines9:20 p.m.0.0%0.4%0.3%first flight 8:25 a.m.

Last flight = the airline's last scheduled departure on this route that day, on days it flies the route at least twice; past 12 months. Times are typical scheduled times over the latest three months.

By month

Each calendar month pooled over 2023–2026. Best: November (84%). Worst: April (65%).

40%70%100%Jan: 75% on time (228 flights)75JanFeb: 73% on time (201 flights)73FebMar: 80% on time (253 flights)80MarApr: 65% on time (255 flights)65AprMay: 69% on time (259 flights)69MayJun: 70% on time (285 flights)70JunJul: 72% on time (299 flights)72JulAug: 80% on time (280 flights)80AugSep: 74% on time (280 flights)74SepOct: 78% on time (307 flights)78OctNov: 84% on time (299 flights)84NovDec: 79% on time (297 flights)79Dec

By day of week

DayFlightsOn timeCancelled
Monday16260%0.0%
Tuesday13478%0.8%
Wednesday13083%0.0%
Thursday15471%0.7%
Friday16173%0.0%
Saturday13274%0.8%
Sunday15570%0.7%

Why flights were late

Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.

Airline (crew, maintenance, ops) 54%Late inbound plane 28%Air traffic & airport (NAS) 10%Severe weather 8%

Cancellations: weather 3 · airline 1

Month by month

50%75%100%Sep 2023Jan 2024Jan 2025Jan 2026Sep 2023: 58% on time, 0.0% cancelledOct 2023: 76% on time, 0.0% cancelledNov 2023: 84% on time, 0.9% cancelledDec 2023: 81% on time, 0.0% cancelledApr 2024: 67% on time, 0.9% cancelledMay 2024: 58% on time, 0.9% cancelledJun 2024: 71% on time, 0.0% cancelledJul 2024: 70% on time, 2.6% cancelledOct 2024: 95% on time, 0.0% cancelledNov 2025: 81% on time, 0.0% cancelledDec 2025: 71% on time, 0.0% cancelled
Share of flights on time, by month (hover a point for cancellations)
STL → LAX, monthly on-time and cancellation rate.

Worst days in the past year

DateFlightsOn timeCancelled
Nov 30, 202540%0
May 4, 202630%0
May 18, 202630%0
Feb 16, 202630%0
Nov 29, 202530%0

Questions

How often are flights from STL to LAX on time?

72% of 1,028 scheduled flights from St. Louis, MO to Los Angeles, CA arrived within 15 minutes of schedule between September 2025 and August 2026. 0.4% were cancelled.

What is the best time of day to fly STL to LAX?

Flights scheduled to leave at 8 a.m. were the most reliable (87% on time). The 9 p.m. departures were the least (41%).

Which airline is most on time from STL to LAX?

American Airlines: 74% of its 354 flights on the route arrived on time. Southwest Airlines: 71%.

What month has the most delays from STL to LAX?

April (65% on time). The best month is November (84%), over 2023–2026.

Is the last flight of the day from STL to LAX more likely to be cancelled?

No, the opposite. Each airline's last STL–LAX flight of the day was cancelled 0.0% of the time over the past year, against 0.3% for its earlier flights. If the last flight is cancelled, the next one is usually the following morning.

Related

Domestic flights by the airlines that report to the U.S. DOT, plus their regional partners. "On time" means arriving less than 15 minutes after schedule; cancelled and diverted flights count as not on time. Past performance is a guide, not a forecast. Method.