St Louis Lambert International in July 2026

65.2%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 July 2026, reporting carriers scheduled 5,725 domestic departures from St Louis Lambert International (STL). 65.2% left less than 15 minutes late and 69.8% reached their destination on time; 1.8% were cancelled.

Nationally that month, 68.8% of flights departed on time and 69.4% arrived on time, so STL departures were 3.6 points below the national departure figure.

A year earlier, in July 2025, the airport had 5,855 departures with 68.4% leaving on time: a change of −3.2 points, with flights down 2%.

Flights arriving at STL that month were on time 69.8% of the time (5,728 scheduled arrivals).

Of the delay minutes that carriers assigned to a BTS cause category that month, late-arriving aircraft 48%, air carrier 28% and national aviation system 20%.

On time 69.8%
Arrived 15+ minutes late 27.8%
Cancelled 1.8%
Diverted 0.6%

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

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

Measure	Jul 2026	Jul 2025	STL, 12 months to Jul 2026	All reported flights, Jul 2026
Departed on time	65.2%	68.4%	74.1%	68.8%
Arrived on time	69.8%	70.2%	76.8%	69.4%
Cancelled	1.8%	1.6%	1.3%	2.6%
Average departure delay (late minutes only)	23.0 min	22.9 min	17.6 min	24.1 min
Scheduled departures a day	191	195	174	21,066
Scheduled departures	5,725	5,855	63,318	631,970

Airlines that month

Reporting carrier	Flights	Share	On time	Avg arrival delay	Cancelled
WN Southwest Airlines	3,520	61%	66.4%	14.7 min	0.8%
AA American Airlines	556	10%	79.7%	10.1 min	2.7%
DL Delta Air Lines	508	9%	84.4%	1.5 min	1.2%
UA United Airlines	280	5%	68.2%	17.7 min	2.9%
YX Republic Airline	234	4%	60.7%	15.8 min	12.0%
OO SkyWest Airlines	145	3%	69.0%	21.0 min	2.1%
F9 Frontier Airlines	143	2%	61.5%	33.7 min	0.7%
MQ Envoy Air	142	2%	78.2%	0.5 min	4.2%
AS Alaska Airlines	123	2%	85.4%	-6.9 min	2.4%
OH PSA Airlines	74	1%	67.6%	6.8 min	4.1%

Busiest routes that month

Route	Cities	Flights	On time	Avg arrival delay	Cancelled
STL–DEN	St. Louis to Denver	373	71.3%	13.8 min	0.0%
STL–ATL	St. Louis to Atlanta	330	75.5%	11.1 min	0.6%
STL–ORD	St. Louis to Chicago	309	72.8%	9.5 min	5.2%
STL–MCO	St. Louis to Orlando	232	73.3%	7.9 min	0.9%
STL–DFW	St. Louis to Dallas/Fort Worth	223	71.7%	24.9 min	1.8%
STL–LGA	St. Louis to New York	204	64.7%	7.3 min	6.4%
STL–DCA	St. Louis to Washington	202	59.9%	25.2 min	6.4%
STL–PHX	St. Louis to Phoenix	197	68.5%	24.6 min	0.5%
STL–LAS	St. Louis to Las Vegas	192	64.6%	10.3 min	1.0%
STL–DAL	St. Louis to Dallas	189	66.7%	16.2 min	1.1%
STL–MSP	St. Louis to Minneapolis	186	78.5%	6.6 min	1.1%
STL–CLT	St. Louis to Charlotte	178	77.0%	2.3 min	1.1%

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), July 2026.

Delay causes

BTS cause category	Share of delay minutes	National, Jul 2026	Minutes
Air carrier	27.7%	31.7%	29,434
Late-arriving aircraft	47.8%	41.8%	50,913
National Aviation System	19.5%	19.9%	20,787
Extreme weather	4.6%	6.5%	4,925
Security	0.3%	0.1%	362

106,421 delay minutes on 1,594 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 July 2026?

65.2% of 5,725 scheduled domestic departures left less than 15 minutes late, and 69.8% reached their destination on time. The national figures that month were 68.8% and 69.4%.

How does that compare with a year earlier?

In July 2025, 68.4% of 5,855 departures left on time and 1.6% were cancelled, against 65.2% and 1.8% in July 2026.

Provenance

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