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Route Reliability

Chicago → Ontario

ORD–ONT · 1,700 miles · Chicago O'Hare International Airport to Ontario International Airport

52
A Little Dicey
WanderNerd Reliability Score
58%
Arrive within 15 minutes
28 min
Average arrival delay
1.0%
Cancelled
290
Flights in the data

Data through May 2026.

United Airlines is the only airline in this data on this route, arriving on time 58% of the time across 290 flights. No comparison to make.

What the data says

The 3–6 PM departure wins.

ORD–ONT flights departing between 3–6 PM arrived on time 77% of the time, versus 56% between 6–9 PM.

Mondays have been rough.

ORD–ONT flights arrived on time 70% of the time on Wednesdays and just 50% on Mondays. That gap is worth planning around.

Recent months have been rougher.

ORD–ONT flights arrived on time 52% of the time over the last three months in the data, compared with 67% in the three months before that.

Flights on this route

The breakdown

On-time by weekday
  • Mon50%(40 flights)
  • Tue55%(40 flights)
  • Wed70%(40 flights)
  • Thu59%(41 flights)
  • Fri54%(41 flights)
  • Sat64%(42 flights)
  • Sun51%(43 flights)
On-time by departure window
  • 12–3 PM—(1 flights)
  • 3–6 PM77%(17 flights)
  • 6–9 PM56%(269 flights)
On-time trend by month
58%
May

Jun 50% → May 58% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202550%30
July 202547%30
August 202558%31
September 202560%30
October 202581%31
November 202563%30
December 202557%14
March 202654%26
April 202645%29
May 202658%31

Same trip, other airports

Keep nerding

Based on 290 historical flights, because apparently we checked. Historical flight data: U.S. Bureau of Transportation Statistics, June 2025 – May 2026. Data through May 2026. How we calculate this.