Route profile
ATL→STL
Flight reliability, delays and best times to fly from Atlanta to St. Louis, 484 miles.
Right now
Aviation weather is not currently a factor.
Aviation weather is not currently a factor.
Route reliability
July 2023 – July 2026
Better than 76% of comparable major US routes (4,598 compared)
Calculated from 10,978 flights. How this is calculated
ATL → STL arrives on time 81.7% of the time; the return trip, STL → ATL, arrives on time 85.0% of the time, a 3.4-point gap between the two directions of the same city pair.
ATL → STL spends 21.1 minutes on the ground on a 484-mile trip: 15.3 minutes from pushback to wheels-up at ATL and 5.8 minutes from touchdown to gate at STL.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What stands out
This route has stayed remarkably steady year over year, a smaller swing than 100% of 5,368 comparable routes.
82.0% on time over the most recent 12 months (2025-08 to 2026-07), against 82.0% in the 12 months before (2024-08 to 2025-07), virtually unchanged.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Ranked against every other route with the same kind of figure and at least 5,368 in the comparison.
Why ATL → STL flights are cancelled
July 2023 – July 2026
ATL → STL cancelled 110 of 10,978 scheduled flights — about 1 in every 100. The reason filed most often was the airline, 60.9% of the cancellations coded on this route — about 1 in every 164 scheduled flights.
Share of cancellations
Of 110 cancelled departures carrying a reason code.
What each reason means
Crew, maintenance, aircraft cleaning, baggage or fueling: what BTS counts as within the carrier’s own control.
67 cancellations, 60.9% of the total.
Conditions the carrier judged severe enough to stop the flight: a blizzard, a hurricane, a line of thunderstorms.
43 cancellations, 39.1% of the total.
Airport capacity, air traffic control flow programs, heavy traffic and ordinary bad weather. A system decision, not the airline’s.
0 cancellations, 0.0% of the total.
A terminal evacuation, a security breach, screening equipment failure, or screening queues over 29 minutes.
0 cancellations, 0.0% of the total.
Reason codes are the operating airline’s own filing with US DOT, not an independent finding of fault. Ordinary bad weather is filed under air traffic, so weather’s full share is larger than its bar.
110 coded cancellations were recorded on ATL → STL; the section appears from 50.
When it goes wrong
July 2023 – July 2026
33 min late
against a median of 6 min early
Percentiles over 10,978 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at STL after arriving from ATL.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 34% | Likely to miss |
| 45 min | 18% | High risk |
| 60 min | 11% | Some risk |
| 90 min | 5.1% | Some risk |
| 120 min | 2.9% | Low risk |
This is one leg of a connection. Gate changes and the next flight's own schedule matter too. And a connection can fail before delay is even the question — this route cancels 1.00% of the time and diverts 0.17% of the time, which a late arrival never shows up in.
Chance of missing is the share of 10,849 arrivals on this route that landed later than the connection time less 30 minutes to reach the next gate.
The worst tenth of arrivals on this route land at least 33 minutes late (90th-percentile gate arrival delay), over 10,978 operations.
Any other layover length: connection checker.
Best time to fly
ATL → STL flights departing 5–9 AM arrived on time 89.8% of the time, against 69.8% for 6–9 PM departures, a gap of 20.0 percentage points.
By departure window
By departure hour
- 12 AM to 5 AM: too few flights to score
- 6 AM: 91.9% on time from 162 flights
- 7 AM: 92.2% on time from 482 flights
- 8 AM: 88.7% on time from 1,387 flights
- 9 AM: 87.3% on time from 566 flights
- 10 AM: 86.0% on time from 412 flights
- 11 AM: 88.4% on time from 957 flights
- 12 PM: 81.8% on time from 348 flights
- 1 PM: 84.6% on time from 585 flights
- 2 PM: 82.7% on time from 862 flights
- 3 PM: 84.4% on time from 879 flights
- 4 PM: 75.4% on time from 313 flights
- 5 PM: 77.4% on time from 863 flights
- 6 PM: 80.6% on time from 400 flights
- 7 PM: 73.1% on time from 694 flights
- 8 PM: 60.8% on time from 743 flights
- 9 PM: 77.7% on time from 366 flights
- 10 PM: 78.6% on time from 495 flights
- 11 PM: 76.4% on time from 464 flights
Why ATL → STL runs late
July 2023 – July 2026
crew, maintenance, boarding and fueling, all within the carrier’s control
the inbound aircraft was late, so this flight started late
airspace and airport capacity, including weather-driven flow control
weather severe enough to stop this flight specifically
screening or terminal security incidents
Share of the delay minutes US DOT attributed to each cause for ATL → STL. Only delays of 15 minutes or more are attributed.
How this route holds up in bad weather
July 2023 – July 2026
Bad weather raises cancellations by a similar amount at both ends of ATL to STL: 3.3 times the normal rate at ATL and 3.7 times at STL. Cancelled in bad weather against normal hours: ATL 3.4% against 1.0%, STL 3.5% against 0.9%. Flights that did leave ATL in bad weather arrived on time 66.5% of the time, against 80.2% in normal hours.
Bad weather and normal hours at the airports
Scheduled departures, July 2023 – July 2026| Departures from | ATL | STL |
|---|---|---|
| Cancelled in bad weather | 3.4% | 3.5% |
| Cancelled in normal hours | 1.0% | 0.9% |
| Arrived on time, bad weather | 66.5% | 67.0% |
| Arrived on time, normal hours | 80.2% | 80.4% |
| Departures in bad weather | 105,854 | 18,612 |
Of the carriers on this route, Southwest Airlines (2.1% cancelled against 3.1% for the other carriers at ATL) cancelled the fewest departures from ATL in bad weather and Frontier Airlines (5.0% cancelled against 3.8% for the other carriers at ATL) the most.
This route’s airlines in bad weather at ATL
All departures from ATL| Airline | Bad-weather departures | Cancelled | Other carriers |
|---|---|---|---|
| Southwest Airlines | 8,953 | 2.1%below the others | 3.1% |
| Delta Air Lines | 73,919 | 3.5%about level | 3.6% |
| Frontier Airlines | 4,928 | 5.0%above the others | 3.8% |
These are airport figures, not route figures: every scheduled departure from ATL and STL, to any destination, in hours the weather report called bad. The airline rows count each carrier’s departures from ATL on every route.
Weather source and limits. In full: ATL (airlines), STL, What Weather Costs Each Airport, Who Cancels More When the Weather Turns, Airports That Change Places When Weather Turns.
Airlines on this route
Carriers with at least 200 flights, by the airline that operated each one.
| Carrier | Flights | On time | Cancelled | Median delay | Severe |
|---|---|---|---|---|---|
| Delta Air Lines | 6,975 | 83.8% | 1.13% | -6 min | 4.9% |
| Southwest Airlines | 3,758 | 78.6% | 0.72% | -4 min | 5.7% |
| Frontier Airlines | 245 | 69.3% | 1.63% | -3 min | 9.1% |
Delta Air Lines flew 63.5% of the 10,978 flights listed.
Delta Air Lines arrived on time 14.5 percentage points more often than Frontier Airlines on this route.
Flights on this route
Flight numbers with at least 600 operations here and still on the schedule.
DL1571 (8:20 AM) arrived on time 89.5% of the time, 12.0 points more often than DL1403 (11:00 PM) at 77.5%.
Weekly and seasonal patterns
By day of week
Wednesday is historically the most reliable day and Sunday the least, a gap of 12.5 percentage points.
By month
- Jan: 79.1%
- Feb: 86.2%
- Mar: 81.3%
- Apr: 81.7%
- May: 76.9%
- Jun: 79.7%
- Jul: 73.4%
- Aug: 79.9%
- Sep: 89.7%
- Oct: 87.8%
- Nov: 87.1%
- Dec: 81.3%
July is historically the weakest month and September the strongest, a spread of 16.3 percentage points.
Reliability over time
July 2023 – July 2026
- July 2023: 75.2% from 306 flights
- August 2023: 73.5% from 296 flights
- September 2023: 87.0% from 293 flights
- October 2023: 85.2% from 305 flights
- November 2023: 91.2% from 317 flights
- December 2023: 85.4% from 321 flights
- January 2024: 76.7% from 256 flights
- February 2024: 91.6% from 240 flights
- March 2024: 84.5% from 284 flights
- April 2024: 81.6% from 294 flights
- May 2024: 72.8% from 313 flights
- June 2024: 83.3% from 294 flights
- July 2024: 64.8% from 298 flights
- August 2024: 82.9% from 299 flights
- September 2024: 89.4% from 284 flights
- October 2024: 92.9% from 296 flights
- November 2024: 88.4% from 276 flights
- December 2024: 79.1% from 292 flights
- January 2025: 76.7% from 263 flights
- February 2025: 85.8% from 247 flights
- March 2025: 82.5% from 276 flights
- April 2025: 79.8% from 274 flights
- May 2025: 76.3% from 288 flights
- June 2025: 74.3% from 330 flights
- July 2025: 78.3% from 351 flights
- August 2025: 83.0% from 331 flights
- September 2025: 92.4% from 317 flights
- October 2025: 85.6% from 348 flights
- November 2025: 81.1% from 285 flights
- December 2025: 79.2% from 311 flights
- January 2026: 83.5% from 279 flights
- February 2026: 81.3% from 254 flights
- March 2026: 76.7% from 283 flights
- April 2026: 83.6% from 299 flights
- May 2026: 81.3% from 330 flights
- June 2026: 81.9% from 318 flights
- July 2026: 74.0% from 330 flights
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 82.0% against 82.0% in the 12 months before — broadly unchanged.
Data and methodology
Calculated by FlyerIntel from 10,978 ATL → STL flight records from the US DOT Bureau of Transportation Statistics, covering July 2023 – July 2026. Late means 15 or more minutes past scheduled arrival; cancelled and diverted flights are left out of on-time rates.
Full methodology · Data sources · Report a problem
Related research: How Long a Layover Needs to Be · Two Airlines on One Route · Best Time of Day to Fly From Major US Airports
Analysis last recomputed