ONT Airport: 83.5% on time, worst at 9 PM

ONT right now

Live conditions where a permitted source publishes them, and the historical record where none does.

No disruption reported

Aviation weather is not currently a factor.

Aviation weatherVFR

67°F · wind 3 kt

Minimal operational impact. Conditions are not a notable factor for operations right now.

Updated 08:53 UTC

Forecast issued 05:20Z.

Updated 05:20 UTC

Aircraft seen now

On the field0

Airborne within 15 NM1

Departed in the last hour0

Arrived in the last hour0

Below 10,000 ft, so aircraft overflying at cruise are not counted. These are observations, not an operational status: a count is a floor, since receiver coverage varies and a movement between two samples can be missed.

Updated 08:45 UTC

Aircraft observations from ADSB.lol (opens in a new tab) (Katia Esposito and contributing feeders), under the ODbL 1.0 (opens in a new tab). Derived data.

Parking

Lot 1 International Arrivals $20/day$20.00/day

Lot 2 General $30/day$30.00/day

Lot 2 Premium $35/day$35.00/day

Lot 3 $25/day$25.00/day

Lot 4 General $30/day$30.00/day

Lot 4 Premium $35/day$35.00/day

Lot 5 & 6 $20/day$20.00/day

Valet Parking $40/day$40.00/day

FlyerIntel shows live values only where a permitted source provides them. Sections without data are left empty rather than estimated.

Airport reliability

Departures from ONT, July 2023 – July 2026.

Airport Reliability Score

76/ 100Strong

Better than 88% of major US airports covered by FlyerIntel (64 compared)

Calculated from 79,949 flights. How this is calculated

Departures arriving on time

83.5%

66,034 of 79,075 completed

Cancellation rate

0.90%

719 cancelled

Median arrival delay

-8 min

Average 3.3 min

Severe delays

5.3%

Arrived 60+ minutes late

Delay when late

69 min

Average, when 15+ min late

Departures analyzed

79,949

79,947 arrivals

Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026

What stands out

How this airport compares to others like it, not just to itself.

This airport holds up about the same all year, a steadier seasonal pattern than 94% of 306 comparable airports.

87.4% on time in its best month (February) against 79.3% in its worst (June).

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Ranked against every other airport with the same kind of figure and at least 306 in the comparison.

Why flights are cancelled at ONT

Every cancellation carries a reason code filed by the airline that operated the flight. Departures, July 2023 – July 2026.

Extreme weather accounts for 47.4% of cancelled departures from ONT — about 1 in every 234 scheduled departures. That is 12 points lower than the 59.5% recorded across every airport FlyerIntel covers.

Share of cancellations

Weather47.4%

Airline45.1%

Air traffic7.5%

Security0.0%

Of 719 cancelled departures carrying a reason code.

What each reason means

Extreme weather1 in 234

Conditions the carrier judged severe enough to stop the flight: a blizzard, a hurricane, a line of thunderstorms.

341 cancellations, 47.4% of the total.

The airline1 in 247

Crew, maintenance, aircraft cleaning, baggage or fueling: what BTS counts as within the carrier’s own control.

324 cancellations, 45.1% of the total.

The air traffic system1 in 1,481

Airport capacity, air traffic control flow programs, heavy traffic and ordinary bad weather. A system decision, not the airline’s.

54 cancellations, 7.5% of the total.

Security—

A terminal evacuation, a security breach, screening equipment failure, or screening queues over 29 minutes.

0 cancellations, 0.0% of the total.

719 of 79,949 scheduled departures from ONT were cancelled. Ordinary bad weather is filed under air traffic, so weather’s full share is larger than its bar.

Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026 · Reason codes are each airline’s own filing, not an independent finding of fault. Shown for airports with at least 500 coded cancellations; 719 were recorded at ONT.

Why flights run late at ONT

Where US DOT attributed the delay minutes on departures from ONT.

Late-arriving aircraft45.0%

the inbound aircraft was late, so this flight started late

The airline33.3%

crew, maintenance, boarding and fueling, all within the carrier’s control

Air traffic control19.4%

airspace and airport capacity, including weather-driven flow control

Weather2.2%

weather severe enough to stop this flight specifically

Security0.1%

screening or terminal security incidents

Share of the delay minutes US DOT attributed to each cause for departures from ONT. Only delays of 15 minutes or more are attributed.

Of the 13,154 departures from ONT that left 15 or more minutes late and have a known inbound aircraft, 65% followed a flight that landed 15 or more minutes late. The other 35% left late even though the aircraft had come in on time or early. Across the 64 covered airports that share runs from 47% to 73%, with a median of 62%; ONT’s is the 15th highest.

The late flight is the one the same aircraft flew into ONT just before, found from the tail number in the DOT file. Airlines and hours differ from one airport to the next, so this describes the departures from ONT and does not rate the airport.

An airport is only partly the author of its own delays. Late-arriving aircraft describes the national schedule arriving here more than anything about this airfield. Air traffic control covers airspace and airport capacity, which is where a congested airport shows up; only the airline category sits squarely inside the carriers’ own operation. How differently they run it is further down this page.

Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026

What weather costs at ONT

Departures from ONT by the weather at the airport in the hour they were scheduled to leave, July 2023 – July 2026.

5.1% of scheduled departures from ONT left in an hour of bad weather. 1.6% of them were cancelled, against 0.9% in normal conditions, and 85.5% of the ones that flew arrived on time, against 82.8%. Those hours held 9% of all cancelled departures. That is about 29 more cancellations than the normal-conditions rate would give.

Cancellations were highest in high wind hours: 3.4% of 705 departures, 3.9 times the normal rate.

Airlines filed 47% of ONT’s coded cancellations under extreme weather. By the weather at the airport in the scheduled hour, 9% of cancelled departures were in bad-weather hours. A code is the airline’s stated reason and an hour’s weather is what the airport reported, so the two need not match.

By weather

Scheduled departures, July 2023 – July 2026

Cancellation and on-time rates at ONT by the weather at the airport in the scheduled departure hour
Weather at the airport	Departures	Cancelled	Left on time	Arrived on time	Avg. departure delay
Normal conditionsVFR with no thunderstorm, snow or ice, fog, heavy rain or high wind	66,08682.7% of all	0.9%	81.7%	82.8%	9.8 min
Any bad weatherIFR or LIFR, or a thunderstorm, snow or ice, fog, heavy rain or high wind	4,0965.1% of all	1.6%1.8 times normal	86.7%	85.5%2.7 points above normal	7.6 min
MVFRceiling 1,000 to 3,000 feet or visibility 3 to 5 miles	9,75512.2% of all	0.7%	87.2%	87.5%4.7 points above normal	6.9 min
IFRceiling 500 to 999 feet or visibility 1 to under 3 miles	2,6903.4% of all	1.3%1.5 times normal	88.2%	87.6%4.8 points above normal	5.7 min
LIFRceiling under 500 feet or visibility under 1 mile	6330.8% of all	0.6%	89.0%	88.2%5.4 points above normal	8.7 min
Fogfog or freezing fog reported at the airport	2890.4% of all	0.7%	87.8%	88.4%5.6 points above normal	8.6 min
Heavy rainheavy rain reported at the airport	1670.2% of all	4.8%5.5 times normal	85.5%	88.1%5.3 points above normal	3.5 min
High windwind of 25 knots or more, or gusts of 30 knots or more	7050.9% of all	3.4%3.9 times normal	80.2%	77.2%5.6 points below normal	13.7 min
Low ceilinga broken or overcast layer under 1,000 feet	2,4223.0% of all	0.8%	89.5%	88.2%5.4 points above normal	5.7 min
Low visibilityvisibility under 3 miles	2,1482.7% of all	1.4%1.5 times normal	87.5%	87.5%4.7 points above normal	6.6 min

A departure is counted in every row its hour fits, so the rows overlap and do not add up. Left on time is a departure under 15 minutes late, and arrived on time an arrival under 15 minutes late; cancelled is the share of scheduled departures. Rows with fewer than 120 departures are not scored. Too few departures to score: thunderstorm (89).

This is the weather reported at ONT in the hour a flight was scheduled to leave. It leaves out the weather at the destination and on the way, weather that arrived after the scheduled time, and anything else that goes wrong in a bad hour. An hour takes the worst conditions any report in it gave. Weather was matched to 99.9% of the airport’s scheduled departures; the rest left in hours with no report, or at a scheduled time the flight records cannot place exactly. Bad-weather hours are compared with normal hours at the same airport, not with what the same flights would have done in a clear sky: they also fall more often in some seasons and at some times of day.

Source: FlyerIntel analysis of US DOT BTS flight records and Iowa Environmental Mesonet weather reports · July 2023 – July 2026 · Where the weather comes from, and its limits. All covered airports side by side: What Weather Costs Each Airport.

Turning aircraft around at ONT

Time on the ground between one flight and the next of the same aircraft at ONT, and what a late arrival does to the next departure, July 2023 – July 2026.

The median turn at ONT is scheduled for 50 minutes on the ground and takes 54 minutes, against 56 minutes and 63 minutes across all airports. Aircraft are given less time on the ground here than at the typical airport. The typical turn runs 4 minutes over its schedule, closer to it than the 7 minutes across all airports.

When the aircraft landed 15 or more minutes late (10,397 turns here, 52 minutes late on average), 66% of the turns were finished in no more than the scheduled ground time, against 68% across all airports. 77% of those flights left 15 or more minutes late, against 72%. After an aircraft that landed on time, 8% did (all airports 11%).

Given the turn lengths scheduled here, the network’s rates would give 62% finished in the schedule and 78% leaving late. ONT finishes more late turns in the schedule than the network would, but lateness is passed on about as often. 43% of its late-inbound turns had a scheduled turn of 45 to 59 minutes, against 31% across all airports.

Turns at ONT against all airports

57,535 turns, July 2023 – July 2026

Aircraft turns at ONT against all airports: scheduled and actual time on the ground and what a late inbound aircraft does
Measure	ONT	All airports	All airports, same turn lengths
Median scheduled turn	50 min	56 min	—
Median actual turn	54 min	63 min	—
Turns that began with an aircraft 15+ minutes late	18%	19%	—
Late turns finished within the schedule	66%	68%	62%
Late inbound that left 15+ minutes late	77%	72%	78%
On-time inbound that left 15+ minutes late	8%	11%	—

The last column is the network’s rate at the turn lengths scheduled at ONT, band by band from under 30 minutes to 3 to 6 hours. A turn finishes within the schedule when the aircraft spent no more time on the ground than the schedule gave it.

A turn pairs an aircraft’s landing at ONT with its next departure from it by tail number; the aircraft is never named. These 57,535 turns are 72% of the flights that left ONT in the period; the rest are an aircraft’s first flight after a long stay, flights without a usable inbound, and cancelled flights. Ground time runs from the gate. Turns under 30 minutes are kept, but most leave late even after an on-time landing. Airlines set their own turn schedules, so this describes the airlines that fly at ONT and does not rate the airport.

Source: FlyerIntel analysis of US DOT BTS flight records · July 2023 – July 2026 · Airports side by side: Where a Late Aircraft Gets Its Time Back.

What sets ONT apart

Where ONT’s hours, months, airlines and taxi time differ most from the other airports, July 2023 – July 2026.

Flights scheduled to leave ONT at 10 PM arrive on time 84.7% of the time, 12.8 points better than the 71.9% for that hour at the other airports.

July treats ONT better than it treats the rest of the country: 79.4% on time against 70.1% elsewhere, 9.3 points ahead.

Delta Air Lines does better out of ONT than anywhere else it flies: 91.5% on time here, 82.0% on its other departures, 9.5 points apart.

Hawaiian Airlines’ departures from ONT arrive on time 78.5% of the time, 5.2 points worse than the 83.7% the same airline manages at its other airports.

Taxi-out at ONT averages 13.6 minutes, 5.1 minutes less than the 18.7 minutes elsewhere.

ONT against the other airports

July 2023 – July 2026

Where ONT differs most from the other covered airports, with the flights behind each figure
Measure	ONT	Elsewhere	Gap	Flights behind it
Hour: 10 PM departures	84.7%	71.9%	+12.8 pts	2,194 here, 477,606 elsewhere
Month: July	79.4%	70.1%	+9.3 pts	9,165 here, 1,977,318 elsewhere
Airline: Delta Air Lines	91.5%	82.0%	+9.5 pts	5,693 here, 3,096,432 elsewhere
Airline: Hawaiian Airlines	78.5%	83.7%	−5.2 pts	708 here, 196,776 elsewhere
Taxi-out: Departures	13.6 min	18.7 min	−5.1 min	79,245 here, 17,550,864 elsewhere

"Elsewhere" is every other covered airport together, taken from the same aggregates as this page with ONT’s own flights removed (for airlines, that airline’s flights from all its other airports). Hours, months and airlines appear only where both sides have at least 120 completed flights (airlines 500) and the gap is at least 2 points and 2 standard errors; only the largest gap in each direction is shown. The taxi figure is weighted by departures and has no error estimate, so it appears from 2 minutes.

Best time to fly from ONT

On-time arrival rate by scheduled local departure time: each weekday and hour, and averaged over the week.

Flights departing 5–9 AM arrived on time 91.8% of the time, against 75.4% for 6–9 PM departures — a gap of 16.4 percentage points.

By day and hour

On-time arrival rate for each weekday and scheduled departure hour, in local time.

Sunday 5–6 AM was the most reliable slot at ONT (96.9% on time, 749 flights) and Friday 2–3 PM the least (65.6%, 542 flights).

Hour of departure matters more than day of the week: hourly averages sit a typical 7.0 points from the airport-wide rate, weekday averages 2.0 points.

On-time arrival rate at ONT by weekday and scheduled departure hour, local time. Each button reads out one slot.
Hour	Monday	Tuesday	Wednesday	Thursday	Friday	Saturday	Sunday
5 AM–6 AM
6 AM–7 AM
7 AM–8 AM
8 AM–9 AM
9 AM–10 AM
10 AM–11 AM
11 AM–12 PM
12 PM–1 PM
1 PM–2 PM
2 PM–3 PM
3 PM–4 PM
4 PM–5 PM
5 PM–6 PM
6 PM–7 PM
7 PM–8 PM
8 PM–9 PM
9 PM–10 PM
10 PM–11 PM
11 PM–12 AM

On-time rate, % · stronger color, fewer on time

60–69
70–79
80–89
90–99

Fewer than 120 flights, not scored
Most reliable slot
Least reliable slot

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · On time is arrival within 15 minutes of schedule. Cells round to whole percentages; the table shows one decimal.

Best and worst slots are named only among slots with 500+ flights, and only when the gap is larger than sampling error. Departures before 5 AM (618 flights) are not drawn: no slot in those hours has enough flights to score.

View as tableHide table

On-time arrival rate (%) with flights beneath, by scheduled departure hour and weekday at ONT. A dash means fewer than 120 flights, which are not scored.
Hour	Monday	Tuesday	Wednesday	Thursday	Friday	Saturday	Sunday
5 AM–6 AM	94.3% on time757 flights	95.2% on time608 flights	92.8% on time615 flights	96.6% on time769 flights	95.2% on time769 flights	96.5% on time712 flights	96.9% on time749 flights
6 AM–7 AM	92.3% on time1,621 flights	92.3% on time1,582 flights	91.5% on time1,569 flights	92.8% on time1,607 flights	92.3% on time1,629 flights	93.1% on time1,491 flights	93.7% on time1,579 flights
7 AM–8 AM	90.1% on time604 flights	88.6% on time679 flights	91.7% on time656 flights	88.6% on time625 flights	91.0% on time601 flights	90.9% on time698 flights	91.0% on time624 flights
8 AM–9 AM	85.3% on time684 flights	86.7% on time588 flights	89.0% on time586 flights	88.2% on time654 flights	87.4% on time680 flights	86.5% on time559 flights	88.5% on time641 flights
9 AM–10 AM	86.9% on time523 flights	91.1% on time485 flights	88.7% on time480 flights	91.9% on time539 flights	89.4% on time523 flights	87.8% on time445 flights	88.8% on time532 flights
10 AM–11 AM	81.9% on time885 flights	87.2% on time790 flights	83.0% on time798 flights	85.3% on time894 flights	85.4% on time900 flights	82.6% on time661 flights	83.4% on time778 flights
11 AM–12 PM	83.9% on time638 flights	89.5% on time589 flights	85.0% on time585 flights	82.6% on time642 flights	79.9% on time620 flights	88.0% on time522 flights	87.5% on time615 flights
12 PM–1 PM	78.8% on time751 flights	83.0% on time757 flights	85.6% on time776 flights	81.7% on time745 flights	79.9% on time771 flights	84.7% on time631 flights	81.9% on time701 flights
1 PM–2 PM	77.1% on time865 flights	81.8% on time814 flights	81.0% on time807 flights	78.1% on time833 flights	79.3% on time856 flights	83.8% on time691 flights	78.6% on time804 flights
2 PM–3 PM	75.9% on time544 flights	77.8% on time479 flights	78.6% on time502 flights	73.9% on time540 flights	65.6% on time542 flights	76.7% on time428 flights	69.6% on time523 flights
3 PM–4 PM	67.7% on time497 flights	80.5% on time444 flights	78.6% on time437 flights	69.9% on time475 flights	71.6% on time453 flights	82.5% on time401 flights	68.3% on time442 flights
4 PM–5 PM	73.2% on time671 flights	84.5% on time610 flights	81.2% on time598 flights	77.7% on time654 flights	70.2% on time699 flights	83.3% on time494 flights	68.8% on time635 flights
5 PM–6 PM	81.0% on time620 flights	85.1% on time559 flights	83.2% on time555 flights	72.4% on time581 flights	75.2% on time612 flights	87.8% on time406 flights	79.3% on time540 flights
6 PM–7 PM	73.5% on time632 flights	81.0% on time470 flights	77.5% on time500 flights	73.6% on time630 flights	70.7% on time604 flights	76.6% on time421 flights	69.1% on time541 flights
7 PM–8 PM	74.4% on time523 flights	83.8% on time409 flights	81.1% on time445 flights	75.7% on time535 flights	72.9% on time554 flights	80.7% on time275 flights	71.1% on time545 flights
8 PM–9 PM	77.8% on time454 flights	83.3% on time301 flights	77.0% on time306 flights	75.5% on time440 flights	72.4% on time464 flights	80.2% on time180 flights	70.6% on time528 flights
9 PM–10 PM	75.9% on time248 flights	78.4% on time140 flights	81.5% on time130 flights	68.6% on time222 flights	67.5% on time250 flights	94 flights, too few to score	61.0% on time331 flights
10 PM–11 PM	85.8% on time320 flights	87.9% on time267 flights	87.1% on time284 flights	86.4% on time344 flights	83.0% on time373 flights	80.2% on time262 flights	82.9% on time382 flights
11 PM–12 AM	81.0% on time297 flights	79.6% on time229 flights	81.7% on time235 flights	79.1% on time273 flights	84.1% on time261 flights	75.1% on time235 flights	81.5% on time274 flights

By departure window

All days combined

5–9 AM91.8%

9 AM–12 PM85.8%

12–3 PM79.2%

3–6 PM77.1%

6–9 PM75.4%

9 PM–5 AM79.7%

By departure hour

All days combined

12 AM

3 AM

6 AM

9 AM

12 PM

3 PM

6 PM

9 PM

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Buckets with fewer than 120 flights are not scored.

What parking will cost

Estimated from ONT's own published rates.

Where you would park

Arriving

Returning

Estimated cost

Choose a facility and both dates to see an estimate.

Rates as published by the airport, last read 2026-08-31. Confirm before you travel.

Source: Ontario International Airport · An estimate from published standard rates. Airports vary surcharges, oversize vehicle fees and event pricing, so confirm the price with the airport before you travel.

International arrivals

How long passport control normally takes here, hour by hour and hall by hall. This is the arrivals queue, not departure security — and it is history, not a live wait.

At International Terminal, ONT’s busiest hall, both passport queues run much the same: a typical 16 min on a US passport and 19 min on any other, rising to 30 min on a busy day. Where the two halls agree like this, CBP’s combined figure of 17 min is a fair summary of both — which is not true everywhere, and is why they are shown apart.

Terminal by terminal, across the day

Terminal by terminal, across the day
Terminal	US passports	US busy day	Other passports	Other busy day	Global Entry
International Terminal	16 min	25 min	19 min	30 min	6.2% of arrivals

US passports — International Terminal

12 AM

3 AM

6 AM

9 AM

12 PM

3 PM

6 PM

9 PM

US citizens and lawful permanent residents, who use the US-passport lanes.

All other passports — International Terminal

12 AM

3 AM

6 AM

9 AM

12 PM

3 PM

6 PM

9 PM

Every other arriving passenger, including visa and visa-waiver travelers.

Hour by hour — International Terminal

Hour by hour — International Terminal
Cleared in hour	US passports	US busy day	Other passports	Other busy day	Booths open
10 AM–11 AM	11 min	18 min	14 min	20 min	4
4 PM–5 PM	20 min	29 min	26 min	36 min	5
5 PM–6 PM	19 min	27 min	25 min	35 min	5
6 PM–7 PM	16 min	25 min	21 min	32 min	5
7 PM–8 PM	15 min	24 min	18 min	29 min	5
8 PM–9 PM	16 min	22 min	18 min	25 min	4
9 PM–10 PM	15 min	22 min	17 min	24 min	5
10 PM–11 PM	16 min	24 min	18 min	25 min	5
11 PM–12 AM	16 min	24 min	18 min	25 min	5

US passports: clearing in the 4 PM–5 PM hour typically takes 20 min, against 11 min in the 10 AM–11 AM hour — 9 min between the slowest and fastest of 9 measured hours.

All other passports: clearing in the 4 PM–5 PM hour typically takes 26 min, against 14 min in the 10 AM–11 AM hour — 12 min between the slowest and fastest of 9 measured hours.

The hour is when CBP processed the passenger, not when the aircraft landed — allow for the walk from the gate. Hours with fewer than 120 days of records are not listed rather than shown as an estimate, which is why a terminal’s quietest hours are usually absent. “Busy day” is the 90th percentile: one arrival in ten is worse than that. Booths are how many CBP had open, and they follow the queue rather than prevent it — the busiest hours are staffed hardest and are still the slowest.

Source: US Customs and Border Protection · 2024-08-28 to 2026-10-16 · These are CBP passport control waits for arriving international passengers — a different queue from TSA departure screening. CBP publishes them about two days in arrears, so every figure here describes what has been typical over 2024-08-28 to 2026-10-16, and none of it is a live queue or a forecast for your flight. US and non-US passengers are reported separately by CBP and are kept separate here, because they are separate halls. FlyerIntel publishes a terminal or an hour only where CBP filed at least 120 hourly records for it, and an hour-by-hour breakdown only where at least 6 hours clear that floor.

What to expect at ONT

How busy the airport is through the day, from scheduled departure volume.

Departures a day

71

Average across the analysis period

Busiest hour

6 AM

About 10 departures

Typical taxi-out

13.6 min

Pushback to wheels-up, on departure

Typical taxi-in

5.2 min

Touchdown to gate, on arrival

Scheduled departures by hour

12 AM

3 AM

6 AM

9 AM

12 PM

3 PM

6 PM

9 PM

The busiest hour is 6 AM, with about 10 departures a day, against roughly 1 at 9 PM. That peak is also more punctual than a typical hour here: early banks fly aircraft that spent the night on the ground rather than ones inheriting the day’s delays.

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Taxi-out runs from gate to wheels-up, averaged over departures and weighted by hour. Taxi-in runs from touchdown to gate.

Weekly and seasonal patterns

By day of week

Mon82.0%

Tue86.3%

Wed85.1%

Thu82.8%

Fri81.3%

Sat86.1%

Sun81.7%

Tuesday is historically the most reliable day and Friday the least, a gap of 5.0 percentage points.

By month

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

June is historically the weakest month and February the strongest, a spread of 8.1 percentage points.

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026

Airlines at ONT

Departure performance by operating carrier. Regional flights are reported by the carrier that operated them, not by the mainline brand.

Airlines at ONT
Carrier	Departures	On time	Cancelled	Median delay
Southwest Airlines WN	35,384	84.1%	0.48%	-7 min
American Airlines AA	10,643	83.1%	1.47%	-9 min
Frontier Airlines F9	8,582	74.6%	1.76%	-7 min
SkyWest Airlines OO	7,038	86.8%	0.43%	-9 min
Delta Air Lines DL	5,784	91.5%	1.21%	-13 min
United Airlines UA	5,674	82.4%	0.62%	-8 min
Alaska Airlines AS	5,140	84.3%	1.65%	-7 min
JetBlue B6	742	72.5%	2.43%	-7 min
Hawaiian Airlines HA	715	78.5%	0.56%	-3 min

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Carriers with fewer than 500 departures are not listed.

Reliability over time

On-time arrival rate for departures, by month.

24

25

26

Over the most recent 12 months (2025-08 to 2026-07), departures from ONT arrived on time 82.1% of the time, against 84.9% in the 12 months before — declining by 2.8 percentage points.

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026

Data and sources

Historical statistics

Every historical figure on this page is calculated by FlyerIntel from US DOT Bureau of Transportation Statistics on-time performance records covering July 2023 – July 2026, comprising 79,949 departures from ONT. A flight counts as delayed when it arrives 15 or more minutes after schedule.

Full methodology · All data sources

Analysis last recomputed September 26, 2026

Embed this on your site

Ontario International Airport on-time performance, from FlyerIntel

Updates on its own as new data comes in — paste this once, nothing to maintain.

<a href="https://flyerintel.com/airports/ont/"><img src="https://flyerintel.com/badge/airport/ont/" alt="Ontario International Airport on-time performance, from FlyerIntel"></a>

Live conditions

Aviation weather comes from the NOAA Aviation Weather Center. Operational events come from the FAA where available. FlyerIntel shows the age of every live value and does not display data it cannot currently retrieve.

See something wrong? Report it

Latest observation for ONT: METAR KONT 180853Z 36003KT 10SM FEW120 SCT200 19/04 A3001 RMK AO2 SLP149 T01940039 58004 (issued 08:53 UTC).