St Louis Lambert International in October 2025

76.3%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 October 2025, reporting carriers scheduled 5,611 domestic departures from St Louis Lambert International (STL). 76.3% left less than 15 minutes late and 78.2% reached their destination on time; 0.3% were cancelled.

Nationally that month, 80.0% of flights departed on time and 79.1% arrived on time, so STL departures were 3.7 points below the national departure figure.

A year earlier, in October 2024, the airport had 5,762 departures with 86.1% leaving on time: a change of −9.8 points, with flights down 3%.

Flights arriving at STL that month were on time 80.6% of the time (5,607 scheduled arrivals).

Of the delay minutes that carriers assigned to a BTS cause category that month, late-arriving aircraft 45%, air carrier 34% and national aviation system 18%.

On time 78.2%
Arrived 15+ minutes late 21.4%
Cancelled 0.3%
Diverted 0.2%

Every scheduled departure from STL in October 2025, judged by arrival at the destination.

October 2025 against a year earlier, the airport's year and the nation

Measure	Oct 2025	Oct 2024	STL, 12 months to Jul 2026	All reported flights, Oct 2025
Departed on time	76.3%	86.1%	74.1%	80.0%
Arrived on time	78.2%	88.1%	76.8%	79.1%
Cancelled	0.3%	0.8%	1.3%	0.5%
Average departure delay (late minutes only)	15.2 min	8.3 min	17.6 min	13.9 min
Scheduled departures a day	187	192	174	20,195
Scheduled departures	5,611	5,762	63,318	605,844

Airlines that month

Reporting carrier	Flights	Share	On time	Avg arrival delay	Cancelled
WN Southwest Airlines	3,567	64%	77.6%	6.5 min	0.2%
AA American Airlines	549	10%	81.6%	9.5 min	0.5%
DL Delta Air Lines	499	9%	89.4%	-4.3 min	0.2%
UA United Airlines	256	5%	72.7%	7.7 min	0.0%
YX Republic Airline	221	4%	76.0%	6.7 min	1.4%
OO SkyWest Airlines	189	3%	64.6%	28.6 min	0.0%
MQ Envoy Air	125	2%	65.6%	17.9 min	0.8%
F9 Frontier Airlines	112	2%	78.6%	12.5 min	0.9%
AS Alaska Airlines	61	1%	86.9%	-6.0 min	0.0%
OH PSA Airlines	20	0%	75.0%	12.8 min	0.0%
NK Spirit Airlines	12	0%	83.3%	3.5 min	0.0%

Busiest routes that month

Route	Cities	Flights	On time	Avg arrival delay	Cancelled
STL–ATL	St. Louis to Atlanta	348	89.7%	-6.1 min	0.0%
STL–DEN	St. Louis to Denver	334	80.2%	3.8 min	0.0%
STL–ORD	St. Louis to Chicago	274	70.4%	15.9 min	0.0%
STL–DCA	St. Louis to Washington	223	78.9%	6.0 min	0.0%
STL–DFW	St. Louis to Dallas/Fort Worth	209	77.5%	9.1 min	1.9%
STL–PHX	St. Louis to Phoenix	200	74.5%	14.8 min	0.0%
STL–LGA	St. Louis to New York	199	66.8%	12.6 min	2.0%
STL–MCO	St. Louis to Orlando	195	74.4%	12.9 min	0.0%
STL–LAS	St. Louis to Las Vegas	188	76.6%	6.2 min	0.0%
STL–DTW	St. Louis to Detroit	171	86.5%	-1.4 min	0.6%
STL–CLT	St. Louis to Charlotte	162	84.0%	-3.5 min	0.6%
STL–DAL	St. Louis to Dallas	156	73.1%	13.5 min	1.3%

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), October 2025.

Delay causes

BTS cause category	Share of delay minutes	National, Oct 2025	Minutes
Air carrier	33.9%	34.0%	24,494
Late-arriving aircraft	44.9%	39.7%	32,445
National Aviation System	17.8%	22.9%	12,857
Extreme weather	3.5%	3.3%	2,514
Security	0.0%	0.1%	18

72,328 delay minutes on 1,199 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 October 2025?

76.3% of 5,611 scheduled domestic departures left less than 15 minutes late, and 78.2% reached their destination on time. The national figures that month were 80.0% and 79.1%.

How does that compare with a year earlier?

In October 2024, 86.1% of 5,762 departures left on time and 0.8% were cancelled, against 76.3% and 0.3% in October 2025.

Provenance

Source: Bureau of Transportation Statistics, Reporting Carrier On-Time Performance, file for October 2025; 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.