Carrier route record
OHDCA→STL
PSA Airlines · Washington to St. Louis
- Flights
- 615
- Period
- July 2025 to June 2026
- Share of route
- 25%
- Carriers
- 5
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with PSA Airlines.
PSA on DCA to STL draws a C−. About one flight in three arrives at least 15 minutes late, and the typical late arrival is an hour and a half behind schedule. Build slack into anything you connect to. That rests on 615 flights, with a median arrival 1 minute early.
The national on-time rate over the same period is 77.6%, so PSA on DCA to STL runs 10 points behind the country as a whole. Across a thousand flights that is about 102 extra late arrivals.
Key figures
On time
67.4%
Arrivals under 15 minutes late, of 583 completed flights
Avg delay
82 min
Across delayed arrivals only, not all flights
Cancelled
4.88%
National rate is 1.81%
Whole route
73.6%
Every carrier on DCA to STL, 2,414 flights
These figures cover 615 flights between July 2025 and June 2026. Beyond the headline rate, 15.3% 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
PSA against every carrier on DCA to STL
PSA flew 615 of the 2,414 flights on DCA to STL, about 25% of it. Its 67.4% on time is 6 points worse than the route as a whole, which runs 73.6%. Ranked by on-time rate it is last of five carriers on the route, where the range runs from Envoy at 90.5% to PSA at 67.4%. Three 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 |
|---|---|---|---|---|---|
| Envoy Airthin sample | 21 | 90.5% | 39 min | 0.00% | A+ |
| Republic Airwaysthin sample | 200 | 79.8% | 61 min | 3.50% | B− |
| Southwest Airlines | 1,403 | 75.7% | 66 min | 1.21% | B |
| American Airlinesthin sample | 175 | 68.4% | 95 min | 2.29% | C |
| PSA Airlines (this page) | 615 | 67.4% | 82 min | 4.88% | C− |
Departure window
When PSA runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 30 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–8am59 flights80.7%
- 8am–11am86 flights80.0%
- 11am–2pm108 flights68.9%
- 2pm–5pm129 flights65.0%
- 5pm–8pm44 flights51.2%
- 8pm–5am189 flights61.4%
Scale runs 45% to 85%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 51.2% on time, against 80.7% for the 5am–8am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 8pm–5am window is the busiest, with 189 flights scheduled in it.
Across the year
PSA on DCA to STL through the year
January is the weak month at 57.1% on time, against 75.0% in June. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. May was the busiest month here, with 78 flights.
Across the week, Monday is the strongest day at 72.2% on time and Sunday the weakest at 51.4%. 21 points is a smaller lever than departure hour, but it is free.
Delay causes
Why PSA runs late on this route
One category carries most of the weight here. Late-arriving aircraft accounts for 49% of the 16,000 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.
- 49%Late-arriving aircraft
- 33%Carrier
- 11%National Airspace System
- 7%Extreme weather
- 0%Security
49% 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 16,000 reported delay minutes here, that single category outweighs weather by 7 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 15,656 reported delay minutes.
The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 80.7% on time here.
Cancellations run at 4.88%, against 1.81% nationally. That is about one flight in twenty cancelled outright. A cancelled flight is invisible in every on-time figure on this page, so the punctuality numbers above describe only the flights that actually operated.
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. 15.3% 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 719 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 74.1% on time across 615 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. 615 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 PSA on DCA to STL
Put together: the delay figures matter less here than the 4.88% cancellation rate. A late arrival costs you an hour and a half; a cancelled flight costs you the day. Book the 5am–8am departure so there is still a schedule behind you if it goes wrong, and treat a same-day connection as optimistic. 583 completed flights over 12 months sit behind that.
Related
Where to go next
- DCA to STL, every carrier
- PSA on STL to DCA, the return leg
- Republic Airways on DCA to STL79.8%
- Southwest Airlines on DCA to STL75.7%
- American Airlines on DCA to STL68.4%
- PSA Airlines network-wide record
- Ronald Reagan Washington National (DCA) delay statistics
- St. Louis Lambert International (STL) delay statistics
- The US routes with the most cancellations
- Why the first flight of the morning is statistically safest
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.