St. Louis (STL) to Atlanta (ATL): On-Time Performance
Data through May 2026
The calendar drives reliability on STL–ATL. September 2025 flights landed on schedule 95% of the time, but July 2024 dropped to 66% — a gap of 29 points. Across the full period the route averages 85% on-time against a national 78%. Morning departures also hold up better than evening ones (91% vs 76%), which matters most in the rough months.
- On-time
- 85%
- arrived <15 min late
- Avg delay
- 11 min
- completed flights
- Cancelled
- 1.5%
- Flights/day
- 10
- last 12 months
- Duration
- 1h 37m
- scheduled
- Distance
- 484 mi
Best airline from STL to ATL
3 airlines flew this route regularly between 2024-06 and 2026-05.
| Airline | On-time | Avg delay | Cancelled | Flights |
|---|---|---|---|---|
| Delta Air Linesmost reliable | 88% | 10 min | 1.6% | 4,577 |
| Southwest Airlines | 81% | 12 min | 1.2% | 2,375 |
| Frontier Airlines | 61% | 38 min | 1.6% | 184 |
Monthly on-time trend
Best time to fly from STL to ATL
Aim for departures around 5 a.m. (97% on-time); avoid 8 p.m. departures (63%).
By day of week
| Day | On-time | Avg delay |
|---|---|---|
| Monday | 83% | 15 min |
| Tuesday | 87% | 9 min |
| Wednesdaybest | 90% | 6 min |
| Thursday | 88% | 8 min |
| Friday | 85% | 12 min |
| Saturday | 84% | 13 min |
| Sunday | 80% | 16 min |
What causes delays on this route
Share of total delay minutes by cause, as reported by carriers to the US DOT.
- Late-arriving aircraft44%
- Airline operations32%
- National airspace system18%
- Weather6%
Frequently asked questions
- How often are flights from STL to ATL delayed?
- 15% of STL–ATL flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-06 and 2026-05. The average arrival delay across completed flights was 11 minutes.
- Which airline is most reliable from STL to ATL?
- Delta Air Lines has the best on-time record on this route at 88%, based on 4,577 flights. 3 airlines flew STL–ATL frequently enough to compare in this period.
- What is the best time of day to fly from STL to ATL?
- Departures around 5 a.m. have the best record (97% on-time), while departures around 8 p.m. have the worst (63%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
- How long is the flight from STL to ATL?
- The scheduled STL–ATL flight time averages 1h 37m over 484 miles. Actual arrival times vary — flights on this route land 15+ minutes late 15% of the time.
- How often are STL to ATL flights cancelled?
- 1.5% of scheduled flights on this route were cancelled between 2024-06 and 2026-05, at or below the national rate of 1.6%.
- What is the worst month to fly from STL to ATL?
- July 2024 was the roughest month in this dataset, with only 66% of arrivals on time. The best was September 2025 at 95%. If your dates are flexible, that 29-point gap is worth planning around.
Explore related pages
More routes from STL
Based on 7,136 flights, 2024-06–2026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.