Ontario International in November 2025

80.8%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 November 2025, reporting carriers scheduled 2,184 domestic departures from Ontario International (ONT). 80.8% left less than 15 minutes late and 80.1% reached their destination on time; 2.1% were cancelled.

Nationally that month, 78.1% of flights departed on time and 77.3% arrived on time, so ONT departures were 2.7 points above the national departure figure.

A year earlier, in November 2024, the airport had 2,215 departures with 86.5% leaving on time: a change of −5.7 points, with flights down 1%.

Flights arriving at ONT that month were on time 77.7% of the time (2,184 scheduled arrivals).

Of the delay minutes that carriers assigned to a BTS cause category that month, late-arriving aircraft 42%, national aviation system 31% and air carrier 27%.

On time 80.1%
Arrived 15+ minutes late 17.7%
Cancelled 2.1%
Diverted 0.1%

Every scheduled departure from ONT in November 2025, judged by arrival at the destination.

November 2025 against a year earlier, the airport's year and the nation

Measure	Nov 2025	Nov 2024	ONT, 12 months to Jul 2026	All reported flights, Nov 2025
Departed on time	80.8%	86.5%	80.3%	78.1%
Arrived on time	80.1%	86.8%	81.2%	77.3%
Cancelled	2.1%	0.7%	0.9%	2.5%
Average departure delay (late minutes only)	12.4 min	9.3 min	13.7 min	15.6 min
Scheduled departures a day	73	74	71	19,018
Scheduled departures	2,184	2,215	25,854	570,550

Airlines that month

Reporting carrier	Flights	Share	On time	Avg arrival delay	Cancelled
WN Southwest Airlines	994	46%	78.6%	4.4 min	1.8%
AA American Airlines	320	15%	75.9%	4.1 min	3.4%
F9 Frontier Airlines	214	10%	79.0%	4.6 min	0.5%
UA United Airlines	205	9%	82.9%	12.4 min	1.0%
AS Alaska Airlines	194	9%	80.9%	0.3 min	3.1%
DL Delta Air Lines	144	7%	86.8%	-4.4 min	2.8%
OO SkyWest Airlines	113	5%	92.9%	-11.2 min	2.7%

Busiest routes that month

Route	Cities	Flights	On time	Avg arrival delay	Cancelled
ONT–PHX	Ontario to Phoenix	272	71.7%	11.2 min	2.6%
ONT–DEN	Ontario to Denver	220	83.6%	-0.8 min	0.0%
ONT–LAS	Ontario to Las Vegas	216	73.1%	6.0 min	4.2%
ONT–SEA	Ontario to Seattle	211	84.4%	-1.9 min	3.3%
ONT–DFW	Ontario to Dallas/Fort Worth	188	73.4%	7.4 min	2.7%
ONT–SMF	Ontario to Sacramento	178	88.8%	-5.1 min	0.6%
ONT–OAK	Ontario to Oakland	129	82.2%	-1.8 min	2.3%
ONT–SJC	Ontario to San Jose	118	83.9%	2.7 min	0.0%
ONT–SFO	Ontario to San Francisco	105	74.3%	13.9 min	1.9%
ONT–SLC	Ontario to Salt Lake City	88	88.6%	-12.0 min	3.4%
ONT–ATL	Ontario to Atlanta	84	86.9%	-0.6 min	2.4%
ONT–PDX	Ontario to Portland	67	89.6%	-7.3 min	1.5%

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), November 2025.

Delay causes

BTS cause category	Share of delay minutes	National, Nov 2025	Minutes
Air carrier	26.9%	30.2%	6,519
Late-arriving aircraft	41.8%	38.3%	10,115
National Aviation System	30.8%	26.7%	7,447
Extreme weather	0.5%	4.6%	121
Security	0.0%	0.1%	0

24,202 delay minutes on 386 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 November 2025?

80.8% of 2,184 scheduled domestic departures left less than 15 minutes late, and 80.1% reached their destination on time. The national figures that month were 78.1% and 77.3%.

How does that compare with a year earlier?

In November 2024, 86.5% of 2,215 departures left on time and 0.7% were cancelled, against 80.8% and 2.1% in November 2025.

Provenance

Source: Bureau of Transportation Statistics, Reporting Carrier On-Time Performance, file for November 2025; 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.