STL to ATL flight delays

STL ATL St. Louis Lambert to Hartsfield Jackson Atlanta · 484 miles

10,709 flights were scheduled from STL to ATL over July 2023 through June 2026. Of the 10,569 that made the trip, 85.3% reached the gate less than 15 minutes behind schedule. These are arrival figures: “on time” means the flight reached the gate less than 15 minutes behind schedule. Arrivals are what decide whether you make the connection, so route and airline pages are scored on them rather than on pushback.

Data through June 2026 · Bureau of Transportation Statistics

The route in brief

Flights in the window
10,709
Arrived on time
85.3%
Cancelled
1.1%
Scheduled distance
484 miles

Cancellations are counted against everything scheduled. Diverted flights are counted with them rather than as very late arrivals, which is why the on-time share and the cancellation rate do not add up to everything that happened.

Airline by airline

Airlines with at least 100 flights on STL–ATL, busiest first. Same route, same weather, same air traffic — which makes this the fairest comparison on the site.

Airline Arrived on time Typical delay Cancelled Flights
Delta Air Lines 88.5% 75 min 1.2% 6,765
Southwest Airlines 80.8% 55 min 0.9% 3,731
Frontier Airlines 62% 90 min 1.9% 213

Month by month

July was the month to avoid on STL–ATL: 75.1% of flights arrived on time, against 91.8% in September. Each bar pools three years of that calendar month.

Share of flights that arrived on time, by calendar month. Best month in green, worst in amber. The hairline sits at the overall rate, 85.3%.
Arrival on-time share, STL to ATL, by calendar month
Month Share flights that arrived on time Flights
January 85.4% 807
February 87.3% 749
March 83.8% 855
April 86.8% 879
May 80.3% 945
June 83% 943
July 75.1% 954
August 86.6% 941
September 91.8% 896
October 91.8% 940
November 89.6% 876
December 83% 924

Both ends of the route

A route’s record is built out of two airports’ habits. The hour-by-hour grid for each is on its own page.

STL to ATL in one number

STL → ATL

When a flight on this route was late, it was late by about 67 min.

July 2023–June 2026 · 10,709 flights

85.3% of flights arrived on time

Questions about STL to ATL

Which airline is most reliable from STL to ATL?
Delta Air Lines — its flights on this pairing arrived on time 88.5% of the time, with 6,765 scheduled. Frontier Airlines came in at 62% over 213 scheduled. Airlines with fewer than 100 flights on the route are not rated.
What is the worst month to fly STL to ATL?
July, at 75.1% of arrivals on time, with 954 flights scheduled. September was the best of the year at 91.8%.
How late are STL–ATL flights when they are late?
67 min on average, counting only the flights that arrived 15 minutes or more behind schedule. The on-time flights are left out of that average on purpose — mixing them in would flatter it.
How often is the STL to ATL flight cancelled?
1.1% of scheduled flights on this route were cancelled, July 2023 through June 2026. Diverted flights are counted with the cancellations rather than as late arrivals.
Are these departure or arrival numbers?
Arrival. A flight counts as on time here if it reached the gate at ATL less than 15 minutes behind schedule. Airport pages score departures instead, because that is the number you can act on when you pick a booking time.