St Louis Lambert International in March 2026

69.2%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 March 2026, reporting carriers scheduled 5,400 domestic departures from St Louis Lambert International (STL). 69.2% left less than 15 minutes late and 73.2% reached their destination on time; 2.5% were cancelled.

Nationally that month, 72.8% of flights departed on time and 73.2% arrived on time, so STL departures were 3.6 points below the national departure figure.

A year earlier, in March 2025, the airport had 5,379 departures with 79.9% leaving on time: a change of −10.7 points, with flights up 0%.

Flights arriving at STL that month were on time 73.7% of the time (5,400 scheduled arrivals).

Of the delay minutes that carriers assigned to a BTS cause category that month, late-arriving aircraft 44%, air carrier 34% and national aviation system 19%.

On time 73.2%
Arrived 15+ minutes late 24.1%
Cancelled 2.5%
Diverted 0.2%

Every scheduled departure from STL in March 2026, judged by arrival at the destination.

March 2026 against a year earlier, the airport's year and the nation

Measure	Mar 2026	Mar 2025	STL, 12 months to Jul 2026	All reported flights, Mar 2026
Departed on time	69.2%	79.9%	74.1%	72.8%
Arrived on time	73.2%	81.1%	76.8%	73.2%
Cancelled	2.5%	0.9%	1.3%	2.9%
Average departure delay (late minutes only)	21.2 min	14.2 min	17.6 min	20.3 min
Scheduled departures a day	180	179	174	20,403
Scheduled departures	5,400	5,379	63,318	612,102

Airlines that month

Reporting carrier	Flights	Share	On time	Avg arrival delay	Cancelled
WN Southwest Airlines	3,324	62%	72.9%	9.2 min	1.6%
AA American Airlines	531	10%	77.8%	12.8 min	2.4%
DL Delta Air Lines	384	7%	85.2%	2.6 min	3.9%
OO SkyWest Airlines	283	5%	65.4%	26.9 min	6.4%
YX Republic Airline	279	5%	71.0%	12.1 min	5.7%
MQ Envoy Air	158	3%	63.9%	19.4 min	4.4%
F9 Frontier Airlines	150	3%	62.0%	16.7 min	3.3%
UA United Airlines	146	3%	74.0%	6.3 min	1.4%
OH PSA Airlines	92	2%	66.3%	27.6 min	5.4%
AS Alaska Airlines	53	1%	84.9%	1.9 min	3.8%

Busiest routes that month

Route	Cities	Flights	On time	Avg arrival delay	Cancelled
STL–DEN	St. Louis to Denver	317	72.9%	11.3 min	0.3%
STL–ATL	St. Louis to Atlanta	283	76.0%	4.7 min	3.2%
STL–ORD	St. Louis to Chicago	271	60.1%	35.2 min	8.1%
STL–MCO	St. Louis to Orlando	269	69.5%	9.3 min	3.0%
STL–LGA	St. Louis to New York	254	57.5%	27.6 min	9.1%
STL–PHX	St. Louis to Phoenix	233	78.5%	3.5 min	0.4%
STL–LAS	St. Louis to Las Vegas	208	82.7%	-1.4 min	1.0%
STL–DCA	St. Louis to Washington	200	64.5%	24.6 min	3.0%
STL–DFW	St. Louis to Dallas/Fort Worth	186	71.0%	16.8 min	2.7%
STL–MSP	St. Louis to Minneapolis	186	74.7%	14.5 min	3.2%
STL–DAL	St. Louis to Dallas	167	74.9%	4.0 min	1.2%
STL–DTW	St. Louis to Detroit	161	75.8%	13.0 min	3.1%

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), March 2026.

Delay causes

BTS cause category	Share of delay minutes	National, Mar 2026	Minutes
Air carrier	33.8%	33.5%	32,286
Late-arriving aircraft	44.0%	39.3%	42,059
National Aviation System	19.1%	21.0%	18,295
Extreme weather	2.9%	5.9%	2,789
Security	0.2%	0.2%	188

95,617 delay minutes on 1,299 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 March 2026?

69.2% of 5,400 scheduled domestic departures left less than 15 minutes late, and 73.2% reached their destination on time. The national figures that month were 72.8% and 73.2%.

How does that compare with a year earlier?

In March 2025, 79.9% of 5,379 departures left on time and 0.9% were cancelled, against 69.2% and 2.5% in March 2026.

Provenance

Source: Bureau of Transportation Statistics, Reporting Carrier On-Time Performance, file for March 2026; 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.