Carrier route record
AAPHL→STL
American Airlines · Philadelphia to St. Louis
- Flights
- 633
- Period
- July 2025 to June 2026
- Share of route
- 40%
- Carriers
- 4
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with American Airlines.
American on PHL to STL sits in the middle of the pack with a C. Close to three flights in four arrive on time by the DOT's definition, 3 points worse than the national rate of 77.6%. The late ones land a little over an hour behind schedule. That rests on 633 flights, with a median arrival 7 minutes early.
The US average over the same twelve months is 77.6%, so there is little to separate American on PHL to STL from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
74.4%
Arrivals under 15 minutes late, of 625 completed flights
Avg delay
75 min
Across delayed arrivals only, not all flights
Cancelled
1.11%
National rate is 1.81%
Whole route
77.1%
Every carrier on PHL to STL, 1,591 flights
These figures cover 633 flights between July 2025 and June 2026. Beyond the headline rate, 10.7% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Carrier by carrier
American against every carrier on PHL to STL
American flew 633 of the 1,591 flights on PHL to STL, about 40% of it. Its 74.4% on time is 3 points worse than the route as a whole, which runs 77.1%. Ranked by on-time rate it is last of four carriers on the route, where the range runs from Republic at 85.9% to American at 74.4%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Republic Airwaysthin sample | 100 | 85.9% | 64 min | 1.00% | A |
| Southwest Airlines | 725 | 78.4% | 69 min | 0.28% | B+ |
| PSA Airlinesthin sample | 133 | 76.0% | 69 min | 9.02% | B− |
| American Airlines (this page) | 633 | 74.4% | 75 min | 1.11% | C |
Departure window
When American runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 28 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am—
- 8am–11am98 flights89.8%
- 11am–2pm139 flights79.4%
- 2pm–5pm132 flights62.1%
- 5pm–8pm194 flights70.0%
- 8pm–5am70 flights78.3%
Scale runs 55% to 95%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 89.8% of the time, against 62.1% for the afternoon window. That is 28 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5pm–8pm window is the busiest, with 194 flights scheduled in it.
Across the year
American on PHL to STL through the year
July is the worst month at 59.2% on time, 27 points below May, the best at 86.6%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. June was the busiest month here, with 86 flights.
Across the week, Wednesday is the strongest day at 82.4% on time and Thursday the weakest at 68.0%. 14 points is a smaller lever than departure hour, but it is free.
Delay causes
Why American runs late on this route
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 12,000 reported delay minutes.
- 41%Late-arriving aircraft
- 34%Carrier
- 16%National Airspace System
- 9%Extreme weather
41% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 12,000 reported delay minutes here, that single category outweighs weather by 5 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 12,051 reported delay minutes.
The practical consequence: the 8am–11am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 89.8% on time here.
Cancellations sit at 1.11% against a national 1.81%, which is ordinary. Diversions add another 0.16%.
Connections and stage length
What a delay here costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 10.7% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.
The 814 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
The return leg is a different operation and performs like one: it runs 81.3% on time across 630 flights, 7 points above this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 7 points of difference.
One caution: this is a thin sample. 633 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.
What to do with this
Booking American on PHL to STL
Put together: treat all of this as provisional. 633 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 74.4% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 625 completed flights over 12 months sit behind that.
Related
Where to go next
- PHL to STL, every carrier
- American on STL to PHL, the return leg
- Republic Airways on PHL to STL85.9%
- Southwest Airlines on PHL to STL78.4%
- PSA Airlines on PHL to STL76.0%
- American Airlines network-wide record
- Philadelphia International (PHL) delay statistics
- St. Louis Lambert International (STL) delay statistics
- Why the first flight of the morning is statistically safest
- How often a connection fails at the major US hubs
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.