Carrier route record
YXSTL→PHL
Republic Airways · St. Louis to Philadelphia
- Flights
- 100
- Period
- July 2025 to June 2026
- Share of route
- 6%
- Carriers
- 4
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Republic Airways.
Republic on STL to PHL earns a B. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 7 points better than the national rate of 77.6%. When something does go wrong the average delay runs close to two hours. That rests on 100 flights. The strongest carrier on the route with a full sample, American Airlines, flew 630 at 81.3% on time.
Set against the rest of the country, Republic's STL to PHL record is 7 points better than the US average of 77.6%. That gap is worth roughly 71 fewer late arrivals for every thousand flights.
Key figures
On time
84.7%
Arrivals under 15 minutes late, of 98 completed flights
Avg delay
108 min
Across delayed arrivals only, not all flights
Cancelled
2.00%
National rate is 1.81%
Whole route
79.6%
Every carrier on STL to PHL, 1,587 flights
These figures cover 100 flights between July 2025 and June 2026. Beyond the headline rate, 9.2% 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
Republic against every carrier on STL to PHL
Republic flew 100 of the 1,587 flights on STL to PHL, about 6% of it. Its 84.7% on time is 5 points better than the route as a whole, which runs 79.6%. Ranked by on-time rate it is number two of four carriers on the route, where the range runs from PSA at 85.5% to Southwest at 76.3%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The two carriers here are closely matched: 5 points separate the best from the worst. At that spread, schedule and price are better tie-breakers than reliability. Sample sizes are shown so you can see which rows are worth weighing.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| PSA Airlinesthin sample | 133 | 85.5% | 87 min | 6.77% | A− |
| Republic Airways (this page)thin sample | 100 | 84.7% | 108 min | 2.00% | B |
| American Airlines | 630 | 81.3% | 118 min | 1.11% | B |
| Southwest Airlines | 724 | 76.3% | 57 min | 0.55% | B+ |
No carrier stands out. American tops the table at 81.3%, 5 points clear of the bottom, which is inside the range this kind of sample moves year to year.
Departure window
When Republic runs best on this route
Departure time is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 100 flights.
There are not enough flights in each departure window to split Republic's STL to PHL record by time of day without the percentages moving on noise. The headline rate of 84.7% is the reliable figure here.
Across the year
Republic on STL to PHL through the year
- Jul–Sep 20255 flights—
- Oct–Dec 202553 flights84.9%
- Jan–Mar 202637 flights86.1%
- Apr–Jun 20265 flights—
Scale runs 75% to 90%. Rows with fewer than 30 flights show a dash.
Monthly volumes are too low here to break the year into twelve reliable readings. What the twelve-month total says is 84.7% on time across 100 flights.
Split by quarter, Republic on STL to PHL logged 5 flights in Jul–Sep 2025, 53 flights in Oct–Dec 2025, 37 flights in Jan–Mar 2026 and 5 flights in Apr–Jun 2026. Fewer than three of those quarters carried the 30 completed flights this site needs before printing a rate, so the 84.7% annual figure is the one to use.
Delay causes
Why Republic runs late on this route
One category carries most of the weight here. Late-arriving aircraft accounts for 60% of the 1,615 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.
- 60%Late-arriving aircraft
- 16%Extreme weather
- 14%Carrier
- 10%National Airspace System
Extreme weather accounts for 16% of delay minutes, well above the single-digit share typical across the system. Weather delays are lumpy: they arrive as whole bad days rather than as a steady drag, so the monthly strip above is the more useful view of the risk. The national share is 6%, so this operation carries roughly 2.6 times the usual weather exposure. The split is drawn from 1,615 reported delay minutes.
60% 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 1,615 reported delay minutes here, that single category outweighs weather by 4 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.
Cancellations sit at 2.00% against a national 1.81%, which is ordinary. Diversions add another 0.00%.
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. 9.2% 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 runs 85.9% on time across 100 flights, within about a point of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
One caution: this is a thin sample. 100 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 Republic on STL to PHL
Put together: treat all of this as provisional. 100 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 84.7% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 98 completed flights over 12 months sit behind that.
Related
Where to go next
- STL to PHL, every carrier
- Republic on PHL to STL, the return leg
- PSA Airlines on STL to PHL85.5%
- American Airlines on STL to PHL81.3%
- Southwest Airlines on STL to PHL76.3%
- Republic Airways network-wide record
- St. Louis Lambert International (STL) delay statistics
- Philadelphia International (PHL) 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.