Ontario International in October 2023

84.8%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 2023, reporting carriers scheduled 2,215 domestic departures from Ontario International (ONT). 84.8% left less than 15 minutes late and 85.9% reached their destination on time; 0.4% were cancelled.

Nationally that month, 83.8% of flights departed on time and 84.0% arrived on time, so ONT departures were 1.0 points above the national departure figure.

Flights arriving at ONT that month were on time 80.1% of the time (2,216 scheduled arrivals).

Of the delay minutes that carriers assigned to a BTS cause category that month, late-arriving aircraft 58%, air carrier 28% and national aviation system 14%.

On time 85.9%
Arrived 15+ minutes late 13.6%
Cancelled 0.4%
Diverted 0.2%

Every scheduled departure from ONT in October 2023, judged by arrival at the destination.

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

Measure	Oct 2023	Year earlier	ONT, 12 months to Jul 2026	All reported flights, Oct 2023
Departed on time	84.8%	—	80.3%	83.8%
Arrived on time	85.9%	—	81.2%	84.0%
Cancelled	0.4%	—	0.9%	0.4%
Average departure delay (late minutes only)	10.2 min	—	13.7 min	11.0 min
Scheduled departures a day	74	—	71	19,966
Scheduled departures	2,215	—	25,854	598,968

Airlines that month

Reporting carrier	Flights	Share	On time	Avg arrival delay	Cancelled
WN Southwest Airlines	994	45%	85.5%	1.6 min	0.2%
F9 Frontier Airlines	271	12%	72.7%	13.4 min	0.4%
AA American Airlines	245	11%	91.0%	-6.7 min	1.2%
OO SkyWest Airlines	236	11%	91.9%	0.9 min	0.0%
DL Delta Air Lines	151	7%	92.7%	-7.2 min	0.0%
AS Alaska Airlines	146	7%	91.1%	-5.1 min	0.7%
UA United Airlines	110	5%	90.9%	-7.3 min	0.0%
B6 JetBlue Airways	31	1%	67.7%	10.2 min	0.0%
HA Hawaiian Airlines	31	1%	67.7%	8.5 min	3.2%

Busiest routes that month

Route	Cities	Flights	On time	Avg arrival delay	Cancelled
ONT–LAS	Ontario to Las Vegas	270	80.0%	6.4 min	0.0%
ONT–PHX	Ontario to Phoenix	260	89.2%	-2.5 min	0.4%
ONT–DEN	Ontario to Denver	244	85.7%	0.6 min	0.4%
ONT–SEA	Ontario to Seattle	204	91.7%	-4.4 min	0.5%
ONT–DFW	Ontario to Dallas/Fort Worth	201	82.6%	-0.8 min	1.5%
ONT–SFO	Ontario to San Francisco	163	83.4%	7.1 min	0.0%
ONT–SMF	Ontario to Sacramento	160	85.0%	3.3 min	0.0%
ONT–OAK	Ontario to Oakland	144	84.7%	1.0 min	0.7%
ONT–SJC	Ontario to San Jose	130	86.2%	-0.5 min	0.0%
ONT–SLC	Ontario to Salt Lake City	93	91.4%	-1.8 min	0.0%
ONT–ATL	Ontario to Atlanta	78	94.9%	-12.8 min	0.0%
ONT–PDX	Ontario to Portland	35	94.3%	-1.1 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), October 2023.

Delay causes

BTS cause category	Share of delay minutes	National, Oct 2023	Minutes
Air carrier	27.6%	41.3%	5,162
Late-arriving aircraft	58.0%	40.5%	10,849
National Aviation System	14.2%	14.4%	2,653
Extreme weather	0.2%	3.7%	37
Security	0.0%	0.2%	0

18,701 delay minutes on 301 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 ONT on time in October 2023?

84.8% of 2,215 scheduled domestic departures left less than 15 minutes late, and 85.9% reached their destination on time. The national figures that month were 83.8% and 84.0%.

How does that compare with a year earlier?

October 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 October 2023; public domain. Domestic scheduled flights by reporting carriers, totals and averages only. The site's data runs through July 2026. Full record for ONT · methodology · corrections.