St Louis Lambert International in August 2024

78.7%departed on time

BTS: A flight is counted as on time if it arrived less than 15 minutes after its scheduled time. Only carriers with at least 0.5 percent of domestic scheduled passenger revenue report.

In August 2024, reporting carriers scheduled 5,749 domestic departures from St Louis Lambert International (STL). 78.7% left less than 15 minutes late and 79.2% reached their destination on time; 1.4% were cancelled.

Nationally that month, 75.4% of flights departed on time and 74.7% arrived on time, so STL departures were 3.3 points above the national departure figure.

A year earlier, in August 2023, the airport had 5,506 departures with 76.4% leaving on time: a change of +2.3 points, with flights up 4%.

Flights arriving at STL that month were on time 79.1% of the time (5,751 scheduled arrivals).

Of the delay minutes that carriers assigned to a BTS cause category that month, late-arriving aircraft 45%, air carrier 33% and national aviation system 21%.

On time 79.2%
Arrived 15+ minutes late 18.9%
Cancelled 1.4%
Diverted 0.4%

Every scheduled departure from STL in August 2024, judged by arrival at the destination.

August 2024 against a year earlier, the airport's year and the nation

Measure	Aug 2024	Aug 2023	STL, 12 months to Jul 2026	All reported flights, Aug 2024
Departed on time	78.7%	76.4%	74.1%	75.4%
Arrived on time	79.2%	76.6%	76.8%	74.7%
Cancelled	1.4%	1.0%	1.3%	2.1%
Average departure delay (late minutes only)	14.4 min	15.0 min	17.6 min	18.4 min
Scheduled departures a day	192	184	174	20,634
Scheduled departures	5,749	5,506	63,318	619,025

Airlines that month

Reporting carrier	Flights	Share	On time	Avg arrival delay	Cancelled
WN Southwest Airlines	3,587	62%	80.9%	3.1 min	1.0%
AA American Airlines	620	11%	72.4%	18.8 min	2.3%
DL Delta Air Lines	510	9%	88.4%	-0.6 min	0.0%
UA United Airlines	279	5%	69.9%	15.4 min	1.1%
MQ Envoy Air	176	3%	72.7%	7.2 min	2.8%
9E Endeavor Air	139	2%	71.2%	4.2 min	8.6%
YX Republic Airline	119	2%	77.3%	-1.4 min	6.7%
F9 Frontier Airlines	111	2%	73.0%	2.2 min	2.7%
AS Alaska Airlines	87	2%	80.5%	3.8 min	0.0%
NK Spirit Airlines	48	1%	70.8%	28.4 min	6.3%
OO SkyWest Airlines	47	1%	70.2%	6.6 min	0.0%
OH PSA Airlines	26	0%	80.8%	30.9 min	0.0%

Busiest routes that month

Route	Cities	Flights	On time	Avg arrival delay	Cancelled
STL–DEN	St. Louis to Denver	322	77.3%	4.8 min	0.9%
STL–LGA	St. Louis to New York	307	73.9%	3.8 min	7.5%
STL–ATL	St. Louis to Atlanta	299	89.6%	-5.3 min	0.3%
STL–ORD	St. Louis to Chicago	251	70.1%	16.7 min	0.4%
STL–MCO	St. Louis to Orlando	201	80.1%	-3.4 min	4.0%
STL–PHL	St. Louis to Philadelphia	201	70.6%	14.3 min	5.0%
STL–DFW	St. Louis to Dallas/Fort Worth	199	74.9%	25.2 min	2.0%
STL–DCA	St. Louis to Washington	195	79.5%	11.8 min	0.0%
STL–PHX	St. Louis to Phoenix	187	79.1%	-0.3 min	0.5%
STL–LAS	St. Louis to Las Vegas	178	84.8%	1.9 min	0.0%
STL–DAL	St. Louis to Dallas	175	84.0%	-0.5 min	0.0%
STL–MSP	St. Louis to Minneapolis	173	79.8%	3.7 min	0.0%

By scheduled departure hour

On-time share:under 62%6270768288% and over

Share of departures that left less than 15 minutes late, by scheduled hour (local time), August 2024.

Delay causes

BTS cause category	Share of delay minutes	National, Aug 2024	Minutes
Air carrier	32.7%	33.8%	23,693
Late-arriving aircraft	45.4%	39.8%	32,843
National Aviation System	20.6%	20.4%	14,888
Extreme weather	1.2%	5.9%	859
Security	0.2%	0.1%	133

72,416 delay minutes on 1,087 flights that arrived 15 or more minutes late and carried a cause report. Carriers assign the categories; see what each category means.

Questions and answers

How many flights left STL on time in August 2024?

78.7% of 5,749 scheduled domestic departures left less than 15 minutes late, and 79.2% reached their destination on time. The national figures that month were 75.4% and 74.7%.

How does that compare with a year earlier?

In August 2023, 76.4% of 5,506 departures left on time and 1.0% were cancelled, against 78.7% and 1.4% in August 2024.

Provenance

Source: Bureau of Transportation Statistics, Reporting Carrier On-Time Performance, file for August 2024; public domain. Domestic scheduled flights by reporting carriers, totals and averages only. The site's data runs through July 2026. Full record for STL · methodology · corrections.