Route on-time record

LAS to STL: most on-time flights and the best time to fly

Las Vegas (Harry Reid International Airport) to St Louis (St. Louis Lambert International Airport). 2,059 nonstop flights in Jun 2025 to May 2026, 80% arrived within 15 minutes and 0.3% were cancelled. The most reliable flight number was Southwest 1496 at 6:50 AM.

Flying on a specific date? We’ll adjust for the month, the weekday and the forecast.

LAS → STL

Las Vegas to St Louis: 2,059 nonstop flights a year

On time (12 months)

80%

Cancelled

0.3%

avg delay 12 min

Best time to leave

Before 9 AM

93% on time vs 66% 6 to 9 PM

Most reliable airline

Frontier

86% chance on time

Check LAS to STL fares

Fares open on our travel partner (Aviasales). Pick the flight number you chose here.

Most reliable nonstop flights

Ranked by the chance the flight operates and arrives within 15 minutes of schedule, from Jun 2025 to May 2026 records.

#1 · Southwest 1496
6:50 AM → 12:00 PM3h 10m nonstop
Local times, typical schedule. Last flown 2026-05-27.
93%
chance on time
On time (history)
100%
Cancelled
0.0%
Avg arrival delay
0 min
- Arrived on time 100% of the time (16 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 93% on time; 6 to 9 PM: 66%).
- Departs outside LAS's trouble window (10 AM to 4 PM, when 51% of its 104 ground stops and delay programs started).
- Short track record (16 flights), so its score leans on the airline's record at this hour.
Limited track record · 16 flights
Find Southwest 1496 fares Opens this date on Aviasales
#2 · Southwest 3286
6:40 AM → 11:45 AM3h 05m nonstop
Local times, typical schedule. Last flown 2026-05-31. Same departure also flew as Southwest 3586; its record covers all of them.
92%
chance on time
On time (history)
93%
Cancelled
0.0%
Avg arrival delay
4 min
- Arrived on time 93% of the time (84 flights, Jun 2025 to May 2026).
- Never cancelled in 84 scheduled flights.
- Leaves in this route's most on-time window (Before 9 AM: 93% on time; 6 to 9 PM: 66%).
- Departs outside LAS's trouble window (10 AM to 4 PM, when 51% of its 104 ground stops and delay programs started).
Moderate track record · 84 flights
Find Southwest 3286 fares Opens this date on Aviasales
#3 · Frontier 3108
1:51 PM → 7:11 PM3h 25m nonstop
Local times, typical schedule. Last flown 2026-05-31.
88%
chance on time
On time (history)
89%
Cancelled
0.0%
Avg arrival delay
12 min
- Arrived on time 89% of the time (157 flights, Jun 2025 to May 2026).
- Never cancelled in 157 scheduled flights.
- Departs inside LAS's trouble window: 51% of its 104 ground stops and delay programs started between 10 AM and 4 PM.
Moderate track record · 157 flights
Find Frontier 3108 fares Opens this date on Aviasales
#4 · Southwest 157
8:20 AM → 1:30 PM3h 10m nonstop
Local times, typical schedule. Last flown 2026-04-05.
88%
chance on time
On time (history)
94%
Cancelled
0.0%
Avg arrival delay
3 min
- Arrived on time 94% of the time (18 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 93% on time; 6 to 9 PM: 66%).
- Departs outside LAS's trouble window (10 AM to 4 PM, when 51% of its 104 ground stops and delay programs started).
- Short track record (18 flights), so its score leans on the airline's record at this hour.
Limited track record · 18 flights
Find Southwest 157 fares Opens this date on Aviasales
#5 · Frontier 2018
6:05 AM → 11:19 AM3h 21m nonstop
Local times, typical schedule. Last flown 2026-05-20.
88%
chance on time
On time (history)
88%
Cancelled
2.4%
Avg arrival delay
5 min
- Arrived on time 88% of the time (122 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 93% on time; 6 to 9 PM: 66%).
- Departs outside LAS's trouble window (10 AM to 4 PM, when 51% of its 104 ground stops and delay programs started).
Moderate track record · 122 flights
Find Frontier 2018 fares Opens this date on Aviasales
#6 · Southwest 667
8:40 AM → 1:50 PM3h 10m nonstop
Local times, typical schedule. Last flown 2026-04-06.
87%
chance on time
On time (history)
93%
Cancelled
6.7%
Avg arrival delay
3 min
- Arrived on time 93% of the time (14 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 93% on time; 6 to 9 PM: 66%).
- Departs outside LAS's trouble window (10 AM to 4 PM, when 51% of its 104 ground stops and delay programs started).
- Short track record (14 flights), so its score leans on the airline's record at this hour.
Limited track record · 14 flights
Find Southwest 667 fares Opens this date on Aviasales
#7 · Southwest 3816
9:35 AM → 2:50 PM3h 15m nonstop
Local times, typical schedule. Last flown 2026-05-29.
86%
chance on time
On time (history)
91%
Cancelled
0.0%
Avg arrival delay
4 min
- Arrived on time 91% of the time (23 flights, Jun 2025 to May 2026).
- Departs outside LAS's trouble window (10 AM to 4 PM, when 51% of its 104 ground stops and delay programs started).
- Short track record (23 flights), so its score leans on the airline's record at this hour.
Limited track record · 23 flights
Find Southwest 3816 fares Opens this date on Aviasales
#8 · Southwest 2140
10:45 AM → 4:05 PM3h 20m nonstop
Local times, typical schedule. Last flown 2026-05-30.
86%
chance on time
On time (history)
100%
Cancelled
0.0%
Avg arrival delay
0 min
- Arrived on time 100% of the time (8 flights, Jun 2025 to May 2026).
- Departs inside LAS's trouble window: 51% of its 104 ground stops and delay programs started between 10 AM and 4 PM.
- Short track record (8 flights), so its score leans on the airline's record at this hour.
Limited track record · 8 flights
Find Southwest 2140 fares Opens this date on Aviasales
#9 · Southwest 2789
7:55 PM → 1:05 AM3h 10m nonstop
Local times, typical schedule. Last flown 2026-04-06.
78%
chance on time
On time (history)
83%
Cancelled
0.0%
Avg arrival delay
13 min
- Arrived on time 83% of the time (23 flights, Jun 2025 to May 2026).
- Leaves in this route's least on-time window (6 to 9 PM: 66% on time; Before 9 AM: 93%).
- Departs outside LAS's trouble window (10 AM to 4 PM, when 51% of its 104 ground stops and delay programs started).
- Short track record (23 flights), so its score leans on the airline's record at this hour.
Limited track record · 23 flights
Find Southwest 2789 fares Opens this date on Aviasales
#10 · Southwest 2139
1:40 PM → 6:55 PM3h 15m nonstop
Local times, typical schedule. Last flown 2026-04-06.
77%
chance on time
On time (history)
76%
Cancelled
0.0%
Avg arrival delay
11 min
- Arrived on time 76% of the time (33 flights, Jun 2025 to May 2026).
- Never cancelled in 33 scheduled flights.
- Departs inside LAS's trouble window: 51% of its 104 ground stops and delay programs started between 10 AM and 4 PM.
- Short track record (33 flights), so its score leans on the airline's record at this hour.
Limited track record · 33 flights
Find Southwest 2139 fares Opens this date on Aviasales

Airlines on this route

Season-adjusted chance of operating and arriving on time.

Frontier Airlines86%
283 flights · 89% on time as flown · 0.8% cancel
Southwest Airlines79%
1,776 flights · 79% on time as flown · 0.2% cancel

On time by departure time

All airlines, scheduled local departure, Jun 2025 to May 2026.

Before 9 AM93%
710 flights · avg delay 5 min
9 AM to noon85%
231 flights · avg delay 8 min
Noon to 3 PM70%
428 flights · avg delay 16 min
3 to 6 PM75%
442 flights · avg delay 17 min
6 to 9 PM66%
248 flights · avg delay 21 min

Best day: Saturday (85%). Worst: Sunday (73%).

On time by month

All airlines, Jun 2023 to May 2026. Several years per month, so one stormy season doesn't define a month. Travel-month estimates use this seasonal pattern.

What delays this route

Late-arriving aircraft48%
Airline (crew, maintenance, boarding)41%
Air traffic control and airport volume10%

Share of delay minutes by the cause airlines report to the US DOT.

Historical odds, not a guarantee. Built from the US DOT Bureau of Transportation Statistics on-time reports (Jun 2025 to May 2026), FAA ground stop and delay program advisories, and 20 years of airport weather observations. Covers US airlines that report to the DOT; schedules are flights operated recently, so confirm times when you book. ATIS Alerts is not affiliated with any airline. Fares are what Aviasales travelers saw in recent searches (USD, one way, 1 adult), not live quotes; the partner site shows the current price. Fare links go to our travel partner and may earn us a commission at no cost to you. Affiliate disclosure

LAS to STL questions

What time of day is best to fly LAS to STL?: Before 9 AM: 93% of flights arrived on time, against 66% for departures 6 to 9 PM. Later flights inherit delays from earlier ones, so the first departures of the day usually run best.
Which airline is most on time from LAS to STL?: Frontier, with a season-adjusted 86% chance of operating and arriving on time over 283 flights. The adjustment compares each airline with what the route did in the months it flew, so a carrier that skipped a stormy month gets no free credit.
What is the worst month for delays on LAS to STL?: June (70% on time); the best was February (86%), averaged over Jun 2023 to May 2026.
Is this a prediction for my flight?: No. These are historical odds from the US DOT on-time reports, FAA advisories and airport weather records. Check your flight status and the FAA delay board on the day you fly.

More routes from LAS

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