Route on-time record
PHX to STL: most on-time flights and the best time to fly
Phoenix (Phoenix Sky Harbor International Airport) to St Louis (St. Louis Lambert International Airport). 2,289 nonstop flights in Jun 2025 to May 2026, 79% arrived within 15 minutes and 0.3% were cancelled. The most reliable flight number was Southwest 4273 at 5:00 AM.
Flying on a specific date? We’ll adjust for the month, the weekday and the forecast.
PHX → STL
Phoenix to St Louis: 2,289 nonstop flights a year
On time (12 months)
79%
Cancelled
0.3%
avg delay 13 min
Best time to leave
Before 9 AM
91% on time vs 68% 3 to 6 PM
Most reliable airline
Envoy
84% chance on time
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 4273
5:00 AM → 9:50 AM2h 50m nonstop
Local times, typical schedule. Last flown 2026-04-06.
91%
chance on time
- On time (history)
- 93%
- Cancelled
- 0.0%
- Avg arrival delay
- 5 min
- Arrived on time 93% of the time (28 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 91% on time; 3 to 6 PM: 68%).
- Departs outside PHX's trouble window (2 PM to 8 PM, when 43% of its 46 ground stops and delay programs started).
- Short track record (28 flights), so its score leans on the airline's record at this hour.
Limited track record · 28 flights
Find Southwest 4273 fares Opens this date on Aviasales#2 · Southwest 3183
5:15 AM → 10:05 AM2h 50m nonstop
Local times, typical schedule. Last flown 2026-05-30.
91%
chance on time
- On time (history)
- 93%
- Cancelled
- 0.0%
- Avg arrival delay
- 4 min
- Arrived on time 93% of the time (30 flights, Jun 2025 to May 2026).
- Never cancelled in 31 scheduled flights.
- Leaves in this route's most on-time window (Before 9 AM: 91% on time; 3 to 6 PM: 68%).
- Departs outside PHX's trouble window (2 PM to 8 PM, when 43% of its 46 ground stops and delay programs started).
Limited track record · 30 flights
Find Southwest 3183 fares Opens this date on Aviasales#3 · Southwest 1680
5:35 AM → 10:25 AM2h 50m nonstop
Local times, typical schedule. Last flown 2026-05-27.
90%
chance on time
- On time (history)
- 94%
- Cancelled
- 0.0%
- Avg arrival delay
- 3 min
- Arrived on time 94% of the time (16 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 91% on time; 3 to 6 PM: 68%).
- Departs outside PHX's trouble window (2 PM to 8 PM, when 43% of its 46 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 1680 fares Opens this date on Aviasales#4 · Southwest 194
7:45 AM → 12:45 PM3h 00m nonstop
Local times, typical schedule. Last flown 2026-04-06.
87%
chance on time
- On time (history)
- 86%
- Cancelled
- 0.0%
- Avg arrival delay
- 5 min
- Arrived on time 86% of the time (28 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 91% on time; 3 to 6 PM: 68%).
- Departs outside PHX's trouble window (2 PM to 8 PM, when 43% of its 46 ground stops and delay programs started).
- Short track record (28 flights), so its score leans on the airline's record at this hour.
Limited track record · 28 flights
Find Southwest 194 fares Opens this date on Aviasales#5 · Envoy 3415 · sold as American Eagle
6:55 PM → 11:59 PM3h 04m nonstop
Local times, typical schedule. Last flown 2026-05-06.
86%
chance on time
- On time (history)
- 93%
- Cancelled
- 0.0%
- Avg arrival delay
- 6 min
- Arrived on time 93% of the time (30 flights, Jun 2025 to May 2026).
- Never cancelled in 30 scheduled flights.
- Departs inside PHX's trouble window: 43% of its 46 ground stops and delay programs started between 2 PM and 8 PM.
- Short track record (30 flights), so its score leans on the airline's record at this hour.
Limited track record · 30 flights
Find 6:55 PM flight fares Opens this date on Aviasales#6 · SkyWest 4968 · sold as United Express, Delta Connection, American Eagle or Alaska
7:05 PM → 12:12 AM3h 07m nonstop
Local times, typical schedule. Last flown 2026-05-20.
82%
chance on time
- On time (history)
- 86%
- Cancelled
- 0.0%
- Avg arrival delay
- 6 min
- Arrived on time 86% of the time (14 flights, Jun 2025 to May 2026).
- Departs inside PHX's trouble window: 43% of its 46 ground stops and delay programs started between 2 PM and 8 PM.
- Short track record (14 flights), so its score leans on the airline's record at this hour.
Limited track record · 14 flights
Find 7:05 PM flight fares Opens this date on Aviasales#7 · Southwest 3904
8:10 AM → 1:15 PM3h 00m nonstop
Local times, typical schedule. Last flown 2026-05-31.
80%
chance on time
- On time (history)
- 78%
- Cancelled
- 0.0%
- Avg arrival delay
- 9 min
- Arrived on time 78% of the time (45 flights, Jun 2025 to May 2026).
- Never cancelled in 47 scheduled flights.
- Leaves in this route's most on-time window (Before 9 AM: 91% on time; 3 to 6 PM: 68%).
- Departs outside PHX's trouble window (2 PM to 8 PM, when 43% of its 46 ground stops and delay programs started).
Limited track record · 45 flights
Find Southwest 3904 fares Opens this date on Aviasales#8 · Southwest 1540
11:20 AM → 4:10 PM2h 50m nonstop
Local times, typical schedule. Last flown 2026-04-06.
80%
chance on time
- On time (history)
- 82%
- Cancelled
- 0.0%
- Avg arrival delay
- 9 min
- Arrived on time 82% of the time (33 flights, Jun 2025 to May 2026).
- Never cancelled in 33 scheduled flights.
- Departs outside PHX's trouble window (2 PM to 8 PM, when 43% of its 46 ground stops and delay programs started).
- Short track record (33 flights), so its score leans on the airline's record at this hour.
Limited track record · 33 flights
Find Southwest 1540 fares Opens this date on Aviasales#9 · American 2043
7:01 PM → 11:59 PM2h 58m nonstop
Local times, typical schedule. Last flown 2026-04-06.
79%
chance on time
- On time (history)
- 80%
- Cancelled
- 0.7%
- Avg arrival delay
- 19 min
- Arrived on time 80% of the time (147 flights, Jun 2025 to May 2026).
- Departs inside PHX's trouble window: 43% of its 46 ground stops and delay programs started between 2 PM and 8 PM.
Moderate track record · 147 flights
Find American 2043 fares Opens this date on Aviasales#10 · American 890
8:44 AM → 1:51 PM3h 07m nonstop
Local times, typical schedule. Last flown 2026-05-31. Same departure also flew as American 3179, 2303; its record covers all of them.
78%
chance on time
- On time (history)
- 78%
- Cancelled
- 0.3%
- Avg arrival delay
- 13 min
- Arrived on time 78% of the time (317 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 91% on time; 3 to 6 PM: 68%).
- Departs outside PHX's trouble window (2 PM to 8 PM, when 43% of its 46 ground stops and delay programs started).
- 53% of its delay minutes came from the plane arriving late from an earlier flight.
Strong track record · 317 flights
Find American 890 fares Opens this date on Aviasales
Airlines on this route
Season-adjusted chance of operating and arriving on time.
- Envoy Air (sold as American Eagle)84%
30 flights · 93% on time as flown · 0.3% cancel
- SkyWest Airlines (sold as United Express, Delta Connection, American Eagle or Alaska)84%
81 flights · 88% on time as flown · 0.2% cancel
- Frontier Airlines80%
53 flights · 83% on time as flown · 0.7% cancel
- American Airlines79%
524 flights · 79% on time as flown · 0.5% cancel
- Southwest Airlines78%
1,601 flights · 78% on time as flown · 0.2% cancel
On time by departure time
All airlines, scheduled local departure, Jun 2025 to May 2026.
- Before 9 AM91%
631 flights · avg delay 5 min
- 9 AM to noon83%
338 flights · avg delay 9 min
- Noon to 3 PM77%
416 flights · avg delay 15 min
- 3 to 6 PM68%
283 flights · avg delay 18 min
- 6 to 9 PM70%
608 flights · avg delay 20 min
Best day: Wednesday (84%). Worst: Sunday (77%).
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 volume8%
- Severe weather2%
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
PHX to STL questions
- What time of day is best to fly PHX to STL?
- Before 9 AM: 91% of flights arrived on time, against 68% for departures 3 to 6 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 PHX to STL?
- Envoy, with a season-adjusted 84% chance of operating and arriving on time over 30 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 PHX to STL?
- July (72% on time); the best was February (87%), 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 PHX
- STL to PHX (return)
- PHX to DEN 77%
- PHX to LAX 83%
- PHX to SEA 83%
- PHX to LAS 79%
- PHX to SAN 74%
- PHX to SLC 83%
- PHX to ORD 77%
- PHX to DFW 80%
- PHX to SFO 71%
- PHX to SNA 80%
- PHX to ATL 82%
- PHX to PDX 79%
Live status: FAA delays and ground stops