Ontario International in March 2024

80.9%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 2024, reporting carriers scheduled 2,022 domestic departures from Ontario International (ONT). 80.9% left less than 15 minutes late and 81.5% reached their destination on time; 0.3% were cancelled.

Nationally that month, 78.5% of flights departed on time and 78.3% arrived on time, so ONT departures were 2.4 points above the national departure figure.

Flights arriving at ONT that month were on time 78.3% of the time (2,023 scheduled arrivals).

Of the delay minutes that carriers assigned to a BTS cause category that month, late-arriving aircraft 42%, air carrier 35% and national aviation system 22%.

On time 81.5%
Arrived 15+ minutes late 18.0%
Cancelled 0.3%
Diverted 0.1%

Every scheduled departure from ONT in March 2024, judged by arrival at the destination.

March 2024 against a year earlier, the airport's year and the nation

Measure	Mar 2024	Year earlier	ONT, 12 months to Jul 2026	All reported flights, Mar 2024
Departed on time	80.9%	—	80.3%	78.5%
Arrived on time	81.5%	—	81.2%	78.3%
Cancelled	0.3%	—	0.9%	0.9%
Average departure delay (late minutes only)	15.1 min	—	13.7 min	15.7 min
Scheduled departures a day	67	—	71	19,726
Scheduled departures	2,022	—	25,854	591,767

Airlines that month

Reporting carrier	Flights	Share	On time	Avg arrival delay	Cancelled
WN Southwest Airlines	900	45%	83.6%	2.1 min	0.3%
AA American Airlines	300	15%	81.7%	9.2 min	0.3%
F9 Frontier Airlines	256	13%	69.5%	29.0 min	0.8%
DL Delta Air Lines	186	9%	91.4%	-2.9 min	0.0%
OO SkyWest Airlines	142	7%	69.7%	15.1 min	0.0%
AS Alaska Airlines	90	4%	86.7%	-4.5 min	0.0%
UA United Airlines	86	4%	89.5%	-4.6 min	0.0%
B6 JetBlue Airways	31	2%	80.6%	7.2 min	3.2%
HA Hawaiian Airlines	31	2%	77.4%	2.3 min	0.0%

Busiest routes that month

Route	Cities	Flights	On time	Avg arrival delay	Cancelled
ONT–PHX	Ontario to Phoenix	279	82.1%	10.5 min	0.4%
ONT–LAS	Ontario to Las Vegas	237	65.8%	20.3 min	0.0%
ONT–DEN	Ontario to Denver	226	85.0%	-1.2 min	1.3%
ONT–DFW	Ontario to Dallas/Fort Worth	204	81.4%	16.6 min	0.5%
ONT–SEA	Ontario to Seattle	152	90.1%	-7.4 min	0.0%
ONT–SMF	Ontario to Sacramento	152	84.9%	1.2 min	0.0%
ONT–OAK	Ontario to Oakland	130	86.9%	0.2 min	0.8%
ONT–SFO	Ontario to San Francisco	120	55.0%	28.1 min	0.0%
ONT–SJC	Ontario to San Jose	102	88.2%	-1.7 min	0.0%
ONT–SLC	Ontario to Salt Lake City	88	86.4%	6.9 min	0.0%
ONT–ATL	Ontario to Atlanta	62	96.8%	-8.2 min	0.0%
ONT–PDX	Ontario to Portland	53	84.9%	-5.6 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), March 2024.

Delay causes

BTS cause category	Share of delay minutes	National, Mar 2024	Minutes
Air carrier	35.3%	32.1%	9,955
Late-arriving aircraft	41.5%	42.1%	11,709
National Aviation System	22.1%	21.4%	6,231
Extreme weather	0.8%	4.2%	231
Security	0.3%	0.2%	77

28,203 delay minutes on 364 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 March 2024?

80.9% of 2,022 scheduled domestic departures left less than 15 minutes late, and 81.5% reached their destination on time. The national figures that month were 78.5% and 78.3%.

How does that compare with a year earlier?

March 2023 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 March 2024; 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.