Boise Air Terminal in September 2023

89.5%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 September 2023, reporting carriers scheduled 1,808 domestic departures from Boise Air Terminal (BOI). 89.5% left less than 15 minutes late and 88.0% reached their destination on time; 0.2% were cancelled.

Nationally that month, 80.5% of flights departed on time and 80.1% arrived on time, so BOI departures were 9.0 points above the national departure figure.

Flights arriving at BOI that month were on time 86.0% of the time (1,813 scheduled arrivals).

Of the delay minutes that carriers assigned to a BTS cause category that month, air carrier 45%, late-arriving aircraft 34% and national aviation system 17%.

On time 88.0%
Arrived 15+ minutes late 11.8%
Cancelled 0.2%
Diverted 0.1%

Every scheduled departure from BOI in September 2023, judged by arrival at the destination.

September 2023 against a year earlier, the airport's year and the nation

Measure	Sep 2023	Year earlier	BOI, 12 months to Jul 2026	All reported flights, Sep 2023
Departed on time	89.5%	—	83.9%	80.5%
Arrived on time	88.0%	—	82.9%	80.1%
Cancelled	0.2%	—	0.5%	1.2%
Average departure delay (late minutes only)	7.4 min	—	12.2 min	14.1 min
Scheduled departures a day	60	—	65	18,978
Scheduled departures	1,808	—	23,701	569,338

Airlines that month

Reporting carrier	Flights	Share	On time	Avg arrival delay	Cancelled
OO SkyWest Airlines	780	43%	88.7%	-1.6 min	0.0%
WN Southwest Airlines	346	19%	87.6%	-1.0 min	0.6%
DL Delta Air Lines	266	15%	90.2%	-2.8 min	0.4%
UA United Airlines	154	9%	84.4%	2.0 min	0.0%
AA American Airlines	114	6%	90.4%	-4.5 min	0.0%
AS Alaska Airlines	78	4%	88.5%	-6.4 min	0.0%
NK Spirit Airlines	54	3%	70.4%	24.4 min	0.0%
G4 Allegiant Air	16	1%	100.0%	-10.0 min	0.0%

Busiest routes that month

Route	Cities	Flights	On time	Avg arrival delay	Cancelled
BOI–SEA	Boise to Seattle	349	86.2%	-2.9 min	0.0%
BOI–DEN	Boise to Denver	209	86.1%	2.0 min	0.5%
BOI–SLC	Boise to Salt Lake City	138	88.4%	2.0 min	0.7%
BOI–LAS	Boise to Las Vegas	134	76.1%	13.2 min	0.7%
BOI–SFO	Boise to San Francisco	128	81.3%	3.7 min	0.0%
BOI–LAX	Boise to Los Angeles	118	97.5%	-10.2 min	0.0%
BOI–PDX	Boise to Portland	105	90.5%	0.7 min	0.0%
BOI–GEG	Boise to Spokane	98	96.9%	-8.3 min	0.0%
BOI–PHX	Boise to Phoenix	90	87.8%	1.5 min	0.0%
BOI–SJC	Boise to San Jose	67	95.5%	-6.8 min	0.0%
BOI–MSP	Boise to Minneapolis	62	91.9%	-3.1 min	0.0%
BOI–DFW	Boise to Dallas/Fort Worth	60	95.0%	-13.6 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), September 2023.

Delay causes

BTS cause category	Share of delay minutes	National, Sep 2023	Minutes
Air carrier	45.0%	36.4%	5,630
Late-arriving aircraft	34.0%	38.3%	4,261
National Aviation System	17.1%	19.9%	2,136
Extreme weather	3.8%	5.1%	474
Security	0.1%	0.2%	15

12,516 delay minutes on 213 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 BOI on time in September 2023?

89.5% of 1,808 scheduled domestic departures left less than 15 minutes late, and 88.0% reached their destination on time. The national figures that month were 80.5% and 80.1%.

How does that compare with a year earlier?

September 2022 is outside the 36 months on file, or the airport had too few reported flights that month.

Provenance

Source: Bureau of Transportation Statistics, Reporting Carrier On-Time Performance, file for September 2023; public domain. Domestic scheduled flights by reporting carriers, totals and averages only. The site's data runs through July 2026. Full record for BOI · methodology · corrections.