BTS DATA COMPLETE THROUGH JUNE 2026HISTORICAL ODDS · NOT LIVE FLIGHT STATUS
DelayOddsKnow the route before you book
STLATL

St. Louis, MO (STL) to Atlanta, GA (ATL) flight delay odds

Historically, 83.6% of scheduled reportable flights on this direction arrived on time in July 2025–June 2026. The sample includes 3,705 flights.

HISTORICAL ROUTE SIGNALGenerally reliable
83.6%arrived on time
9.3%30+ min late
1.7%cancelled
3,705scheduled flights
Based on July 2025–June 2026; on time means arrival less than 15 minutes late.
60+ minutes late5.0%all scheduled flights
120+ minutes late2.1%all scheduled flights
Diverted0.2%did not reach as scheduled
Average arrival-0.9 mincompleted flights

When is this route most reliable?

The same route can behave differently through the day. These are scheduled departure windows, not actual departure times. Small time windows with fewer than 40 flights are withheld.

Departure windowFlightsOn time30+ minCancelled
Early morning95792.5%3.8%1.4%
Late morning85088.8%5.6%1.6%
Afternoon1,00479.6%12.4%1.5%
Evening89073.6%15.3%2.5%

Weekday comparison

Day-of-week results use at least 30 scheduled flights per row. Look for broad patterns, not tiny percentage differences.

DayFlightsOn time30+ minCancelled
Monday56279.0%14.1%1.6%
Tuesday52086.2%6.5%1.0%
Wednesday51291.4%4.5%0.4%
Thursday56487.2%5.7%0.9%
Friday56083.9%10.2%2.0%
Saturday42580.2%12.7%3.1%
Sunday56277.2%11.7%3.4%

Airline comparison

Marketing-carrier results make codeshare flights easier to compare as travelers buy them. Dedicated route-airline reports require at least 160 flights.

AirlineFlightsOn time30+ minCancelled
Delta Air Lines2,37187.4%7.4%2.0%
Southwest Airlines1,13079.6%11.4%1.2%
Frontier Airlines20461.3%20.1%2.0%

Monthly trend

Month-by-month results show whether a twelve-month average hides an unusual period.

MonthFlightsOn time30+ minCancelled
July 202535180.6%13.4%0.6%
August 202533185.5%9.4%1.5%
September 202531795.0%3.2%0.0%
October 202534889.7%4.9%0.0%
November 202528481.0%10.9%3.2%
December 202531179.1%12.9%1.6%
January 202627982.1%6.1%6.5%
February 202625488.2%5.9%0.8%
March 202628376.0%13.4%3.2%
April 202629984.3%9.7%2.0%
May 202633080.3%10.6%1.2%
June 202631880.8%11.0%1.3%

What drove reported delay minutes?

BTS cause minutes are reported for qualifying delayed flights. These shares describe recorded delay minutes—not the chance that a particular cause will affect your next flight.

Airline33.9%
Late aircraft45.1%
National airspace15.4%
Weather5.6%
Security0.0%
This is historical evidence, not a forecast.

Weather, schedules and operations change. For a trip you have already booked, use the airline or airport for live status.