Best Time to Fly PHX to STL: On-Time Stats by Hour & Airline
Phoenix Sky Harbor International → St Louis Lambert International
Data through July 2026 · Last updated October 18, 2026
Over the last 12 months, 76.6% of Phoenix (PHX) to St. Louis (STL) flights arrived on time (2,316 scheduled flights). That is 1.0 points below the national average of 77.6%.
Among 4 airlines, Envoy Air led with 93.3% on time and Southwest Airlines was last with 75.4%.
Over 24 months, Wednesday was the most reliable day (87% on time) and July the worst month (70%).
The cancellation rate was 0.3% (US average 1.8%).
PHX to STL on-time performance by airline
Last 12 months. Airlines with fewer than 30 completed flights are marked “limited data”.
| Airline | On time | Avg delay when late | Cancelled | Flights |
|---|---|---|---|---|
| Envoy Air | 93.3% | 76 min | 0.0% | 30 |
| Frontier Airlines | 82.7% | 170 min | 1.9% | 53 |
| American Airlines | 78.0% | 67 min | 0.7% | 585 |
| Southwest Airlines | 75.4% | 47 min | 0.2% | 1,620 |
| SkyWest Airlines | Limited data | 28 | ||
80%+ good 70–79.9% fair <70% poor
Best time of day to fly PHX to STL
On-time arrival % by scheduled departure hour (local time), 4,622 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 12am–1am | Limited data | 1 | |
| 5am–6am | 94.0% | 0.0% | 404 |
| 6am–7am | 96.6% | 0.4% | 237 |
| 7am–8am | 95.7% | 0.6% | 163 |
| 8am–9am | 85.8% | 0.2% | 513 |
| 9am–10am | 86.3% | 0.5% | 368 |
| 10am–11am | 85.4% | 0.8% | 124 |
| 11am–12pm | 82.6% | 0.7% | 135 |
| 12pm–1pm | 82.2% | 0.3% | 333 |
| 1pm–2pm | 78.8% | 0.7% | 299 |
| 2pm–3pm | 66.1% | 0.6% | 172 |
| 3pm–4pm | 81.0% | 0.7% | 148 |
| 4pm–5pm | 64.6% | 0.4% | 268 |
| 5pm–6pm | 73.2% | 0.7% | 155 |
| 6pm–7pm | 74.7% | 0.4% | 495 |
| 7pm–8pm | 80.0% | 0.0% | 488 |
| 8pm–9pm | 58.0% | 1.7% | 299 |
| 9pm–10pm | Limited data | 18 | |
| 10pm–11pm | Limited data | 1 | |
| 11pm–12am | Limited data | 1 | |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on PHX to STL
On-time arrivals during holiday periods compared with all other days, last 24 months.
| Period | On time | vs other days | Cancelled | Flights |
|---|---|---|---|---|
| Thanksgiving week (Tue before to Mon after) | 79.2% | -3.2 pts | 0.0% | 101 |
| Christmas & New Year (Dec 20 - Jan 3) | 76.2% | -6.2 pts | 0.0% | 210 |
| Summer peak (Jun 15 - Aug 15) | 72.0% | -10.4 pts | 0.3% | 712 |
| All other days | 82.4% | — | 0.5% | 3,599 |
Monthly on-time trend
On-time arrival % each month, with the 12-month US average for reference.
What causes delays on this route
Share of reported delay minutes, last 12 months (BTS cause categories).