Carrier route record

YXPHL→STL

Republic Airways · Philadelphia to St. Louis

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 PHL to STL earns an A. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 8 points better than the national rate of 77.6%. When something does go wrong the average delay runs about an hour. That rests on 100 flights. The strongest carrier on the route with a full sample, Southwest Airlines, flew 725 at 78.4% on time.

Set against the rest of the country, Republic's PHL to STL record is 8 points better than the US average of 77.6%. That gap is worth roughly 83 fewer late arrivals for every thousand flights.

On time

85.9%

Arrivals under 15 minutes late, of 99 completed flights

Avg delay

64 min

Across delayed arrivals only, not all flights

Cancelled

1.00%

National rate is 1.81%

Whole route

77.1%

Every carrier on PHL to STL, 1,591 flights

These figures cover 100 flights between July 2025 and June 2026. The median arrival is 6 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.

Carrier by carrier

Republic against every carrier on PHL to STL

Republic flew 100 of the 1,591 flights on PHL to STL, about 6% of it. Its 85.9% on time is 9 points better than the route as a whole, which runs 77.1%. Ranked by on-time rate it is first of four carriers on the route, where the range runs from Republic at 85.9% to American at 74.4%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.

The two carriers here are closely matched: 4 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.

On-time performance by carrier on PHL to STL
Airline	Flights	On time	Avg delay	Cancelled	Grade
Republic Airways (this page)thin 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	633	74.4%	75 min	1.11%	C

No carrier stands out. Southwest tops the table at 78.4%, 4 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 PHL to STL record by time of day without the percentages moving on noise. The headline rate of 85.9% is the reliable figure here.

Across the year

Republic on PHL to STL through the year

Jul–Sep 20255 flights—
Oct–Dec 202553 flights81.1%
Jan–Mar 202637 flights88.9%
Apr–Jun 20265 flights—

Scale runs 75% to 95%. 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 85.9% on time across 100 flights.

Split by quarter, Republic on PHL to STL 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 85.9% 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 43% of the 897 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.

Late-arriving aircraft
43%
National Airspace System
23%
Extreme weather
21%
Carrier
13%

Extreme weather accounts for 21% 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 3.3 times the usual weather exposure. The split is drawn from 897 reported delay minutes.

43% 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 897 reported delay minutes here, that single category outweighs weather by 2 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 1.00% against a national 1.81%, which is ordinary. Diversions add another 0.00%.

Connections and stage length

What a delay here costs

Badly late arrivals are rare here: only 4.0% land an hour or more behind schedule, against 8.1% nationally. Connections built on this flight are about as safe as US domestic connections get, though a cancelled flight still ignores every layover you give it.

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 84.7% 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 PHL to STL

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 85.9% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 99 completed flights over 12 months sit behind that.

Where to go next

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.

Key figures