Route on-time record
STL to PHX: most on-time flights and the best time to fly
St Louis (St. Louis Lambert International Airport) to Phoenix (Phoenix Sky Harbor International Airport). 2,287 nonstop flights in Jun 2025 to May 2026, 76% arrived within 15 minutes and 0.4% were cancelled. The most reliable flight number was Envoy 4236 at 8:00 AM.
Flying on a specific date? We’ll adjust for the month, the weekday and the forecast.
STL → PHX
St Louis to Phoenix: 2,287 nonstop flights a year
On time (12 months)
76%
Cancelled
0.4%
avg delay 19 min
Best time to leave
Before 9 AM
89% on time vs 54% after 9 PM
Most reliable airline
Envoy
84% chance on time
Lowest nonstop fare seen in the next two months: $190 (American 590 on 2026-10-20). 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 · Envoy 4236 · sold as American Eagle
8:00 AM → 9:37 AM3h 37m nonstop
Local times, typical schedule. Last flown 2026-05-07.
95%
chance on time
- On time (history)
- 100%
- Cancelled
- 0.0%
- Avg arrival delay
- 2 min
- Arrived on time 100% of the time (30 flights, Jun 2025 to May 2026).
- Never cancelled in 30 scheduled flights.
- Leaves in this route's most on-time window (Before 9 AM: 89% on time; After 9 PM: 54%).
- Short track record (30 flights), so its score leans on the airline's record at this hour.
Limited track record · 30 flights
Find 8:00 AM flight fares Opens this date on Aviasales#2 · Southwest 2013
6:05 AM → 7:30 AM3h 25m nonstop
Local times, typical schedule. Last flown 2026-05-31.
92%
chance on time
- On time (history)
- 98%
- Cancelled
- 0.0%
- Avg arrival delay
- 2 min
- Arrived on time 98% of the time (54 flights, Jun 2025 to May 2026).
- Never cancelled in 54 scheduled flights.
- Leaves in this route's most on-time window (Before 9 AM: 89% on time; After 9 PM: 54%).
- Short track record (54 flights), so its score leans on the airline's record at this hour.
Limited track record · 54 flights
Find Southwest 2013 fares Opens this date on Aviasales#3 · Southwest 2847
5:15 AM → 6:50 AM3h 35m nonstop
Local times, typical schedule. Last flown 2026-04-06.
90%
chance on time
- On time (history)
- 94%
- Cancelled
- 0.0%
- Avg arrival delay
- 5 min
- Arrived on time 94% of the time (33 flights, Jun 2025 to May 2026).
- Never cancelled in 33 scheduled flights.
- Leaves in this route's most on-time window (Before 9 AM: 89% on time; After 9 PM: 54%).
- Short track record (33 flights), so its score leans on the airline's record at this hour.
Limited track record · 33 flights
Find Southwest 2847 fares Opens this date on Aviasales#4 · SkyWest 4969 · sold as United Express, Delta Connection, American Eagle or Alaska
8:00 AM → 9:40 AM3h 40m nonstop
Local times, typical schedule. Last flown 2026-05-20.
90%
chance on time
- On time (history)
- 92%
- Cancelled
- 0.0%
- Avg arrival delay
- 16 min
- Arrived on time 92% of the time (13 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 89% on time; After 9 PM: 54%).
- Short track record (13 flights), so its score leans on the airline's record at this hour.
Limited track record · 13 flights
Find 8:00 AM flight fares Opens this date on Aviasales#5 · Southwest 3393
8:30 AM → 9:55 AM3h 25m nonstop
Local times, typical schedule. Last flown 2026-05-31.
86%
chance on time
- On time (history)
- 88%
- Cancelled
- 0.0%
- Avg arrival delay
- 12 min
- Arrived on time 88% of the time (24 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 89% on time; After 9 PM: 54%).
- 69% of its delay minutes came from the plane arriving late from an earlier flight.
- Short track record (24 flights), so its score leans on the airline's record at this hour.
Limited track record · 24 flights
Find Southwest 3393 fares Opens this date on Aviasales#6 · American 2574
7:58 AM → 9:38 AM3h 40m nonstop
Local times, typical schedule. Last flown 2026-05-31.
83%
chance on time
- On time (history)
- 84%
- Cancelled
- 1.0%
- Avg arrival delay
- 36 min
- Arrived on time 84% of the time (286 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 89% on time; After 9 PM: 54%).
Strong track record · 286 flights
Find American 2574 fares Opens this date on Aviasales#7 · Southwest 4701
12:00 PM → 1:30 PM3h 30m nonstop
Local times, typical schedule. Last flown 2026-04-01.
82%
chance on time
- On time (history)
- 100%
- Cancelled
- 0.0%
- Avg arrival delay
- 1 min
- Arrived on time 100% of the time (8 flights, Jun 2025 to May 2026).
- Short track record (8 flights), so its score leans on the airline's record at this hour.
Limited track record · 8 flights
Find Southwest 4701 fares Opens this date on Aviasales#8 · American 2303
2:31 PM → 4:04 PM3h 33m nonstop
Local times, typical schedule. Last flown 2026-04-06.
80%
chance on time
- On time (history)
- 80%
- Cancelled
- 0.7%
- Avg arrival delay
- 25 min
- Arrived on time 80% of the time (136 flights, Jun 2025 to May 2026).
- Lands inside PHX's trouble window: 43% of its 46 ground stops and delay programs started between 2 PM and 8 PM.
Moderate track record · 136 flights
Find American 2303 fares Opens this date on Aviasales#9 · American 890
2:37 PM → 4:00 PM3h 23m nonstop
Local times, typical schedule. Last flown 2026-05-20.
80%
chance on time
- On time (history)
- 80%
- Cancelled
- 0.0%
- Avg arrival delay
- 14 min
- Arrived on time 80% of the time (44 flights, Jun 2025 to May 2026).
- Never cancelled in 44 scheduled flights.
- Lands inside PHX's trouble window: 43% of its 46 ground stops and delay programs started between 2 PM and 8 PM.
- Short track record (44 flights), so its score leans on the airline's record at this hour.
Limited track record · 44 flights
Find American 890 fares Opens this date on Aviasales#10 · Southwest 2940
11:35 AM → 1:00 PM3h 25m nonstop
Local times, typical schedule. Last flown 2026-05-29. Same departure also flew as Southwest 1785; its record covers all of them.
78%
chance on time
- On time (history)
- 82%
- Cancelled
- 0.0%
- Avg arrival delay
- 8 min
- Arrived on time 82% of the time (56 flights, Jun 2025 to May 2026).
- Never cancelled in 56 scheduled flights.
- Short track record (56 flights), so its score leans on the airline's record at this hour.
Limited track record · 56 flights
Find Southwest 2940 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 · 100% on time as flown · 0.4% cancel
- SkyWest Airlines (sold as United Express, Delta Connection, American Eagle or Alaska)81%
79 flights · 84% on time as flown · 0.3% cancel
- American Airlines81%
524 flights · 82% on time as flown · 0.7% cancel
- Frontier Airlines79%
53 flights · 83% on time as flown · 0.8% cancel
- Southwest Airlines74%
1,601 flights · 74% on time as flown · 0.3% cancel
On time by departure time
All airlines, scheduled local departure, Jun 2025 to May 2026.
- Before 9 AM89%
766 flights · avg delay 18 min
- 9 AM to noon83%
243 flights · avg delay 9 min
- Noon to 3 PM77%
489 flights · avg delay 16 min
- 3 to 6 PM66%
231 flights · avg delay 20 min
- 6 to 9 PM62%
392 flights · avg delay 28 min
- After 9 PM54%
166 flights · avg delay 26 min
Best day: Wednesday (81%). Worst: Sunday (76%).
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 aircraft44%
- Airline (crew, maintenance, boarding)41%
- Air traffic control and airport volume10%
- Severe weather5%
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
STL to PHX questions
- What time of day is best to fly STL to PHX?
- Before 9 AM: 89% of flights arrived on time, against 54% for departures after 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 STL to PHX?
- 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 STL to PHX?
- July (70% on time); the best was February (84%), 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 STL
- PHX to STL (return)
- STL to ATL 85%
- STL to DEN 75%
- STL to ORD 71%
- STL to LGA 75%
- STL to MCO 78%
- STL to DCA 73%
- STL to DFW 74%
- STL to LAS 79%
- STL to DAL 77%
- STL to DTW 83%
- STL to MSP 80%
- STL to CLT 83%
Live status: FAA delays and ground stops