BTS DATA COMPLETE THROUGH JUNE 2026HISTORICAL ODDS · NOT LIVE FLIGHT STATUS
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ONT→OAK

Ontario, CA (ONT) to Oakland, CA (OAK) flight delay odds

85.9% of 1,490 official scheduled ONT-to-OAK flights arrived on time; 8.9% arrived at least 30 minutes late and 0.4% were cancelled during July 2025–June 2026.

Source: U.S. Bureau of Transportation Statistics · Reporting window: July 2025–June 2026 · Updated September 16, 2026

HISTORICAL ROUTE SIGNALLower disruption
85.9%arrived on time
8.9%30+ min late
0.4%cancelled
1,490scheduled flights
Based on July 2025–June 2026; on time means arrival less than 15 minutes late.
60+ minutes late4.1%all scheduled flights
120+ minutes late1.3%all scheduled flights
Diverted0.0%did not reach as scheduled
Average arrival-2.1 mincompleted flights

Which departure time was most reliable for ONT to OAK?

Among qualifying ONT-to-OAK departure window results, Early morning had the highest on-time rate: 96.6% of 328 flights. Night was lowest at 73.5% across 49 flights.

Departure windowFlightsOn time30+ minCancelled
Early morning32896.6%3.0%0.0%
Late morning32193.1%3.1%0.0%
Afternoon39781.6%10.8%0.8%
Evening39577.0%15.2%0.8%
Night4973.5%20.4%0.0%

Which weekday was most reliable for ONT to OAK?

Among qualifying ONT-to-OAK weekday results, Wednesday had the highest on-time rate: 90.7% of 204 flights. Sunday was lowest at 74.9% across 231 flights.

DayFlightsOn time30+ minCancelled
Monday22989.5%7.9%0.0%
Tuesday21288.7%6.6%0.5%
Wednesday20490.7%4.9%0.0%
Thursday22786.3%8.8%0.0%
Friday23083.9%8.3%1.7%
Saturday15789.2%8.3%0.0%
Sunday23174.9%16.9%0.4%

Which airline was most reliable for ONT to OAK?

Only Southwest Airlines met the ONT-to-OAK airline threshold: 85.9% of 1,490 scheduled flights arrived on time during July 2025–June 2026.

AirlineFlightsOn time30+ minCancelled
Southwest Airlines1,49085.9%8.9%0.4%

Which month was most reliable for ONT to OAK?

Among qualifying ONT-to-OAK month results, March 2026 had the highest on-time rate: 96.7% of 121 flights. June 2026 was lowest at 75.7% across 111 flights.

MonthFlightsOn time30+ minCancelled
July 202513588.1%11.1%0.0%
August 202513590.4%7.4%0.0%
September 202513391.0%5.3%0.0%
October 202513681.6%13.2%0.0%
November 202512982.2%6.2%2.3%
December 202512179.3%11.6%0.0%
January 202612089.2%5.8%1.7%
February 202611589.6%6.1%0.9%
March 202612196.7%3.3%0.0%
April 202611685.3%9.5%0.0%
May 202611880.5%14.4%0.0%
June 202611175.7%13.5%0.0%

What drove ONT to OAK delay minutes?

Late aircraft was the largest recorded ONT-to-OAK delay category, accounting for 64.7% of 11,467 BTS-attributed delay minutes during July 2025–June 2026.

Airline31.4%
Late aircraft64.7%
National airspace3.7%
Weather0.1%
Security0.1%
This is historical evidence, not a forecast.

Weather, schedules and operations change. For a trip you have already booked, use the airline or airport for live status.