Historical on-time performance
Ontario to Atlanta
1,900 miData through May 2026Source: US DOT · BTS
Flights on ONT–ATL arrive on time 88% of the time over the last 12 months.
On-time rate88%arrived within 15 min
p90 delay15 min1 in 10 flights is worse (tail risk)
Cancelled1.8%of scheduled flights
based on 941 flights over the last 12 months. On-time means arriving within 15 minutes (BTS standard).
By airline
How each carrier compares
- Delta Air LinesOn-time88%Medianon timep9015 minCancel1.8%Flights941
Why flights run late
Delay causes
- Airline62%
- Weather1%
- Air traffic (NAS)9%
- Late aircraft27%
- Security2%
Most delay minutes here are attributed to Airline.
When flights don't go
Why flights were cancelled
- Airline65%
- Weather35%
- Air traffic (NAS)0%
- Security0%
Most cancellations here are attributed to Airline. Shares are among 17 cancellations with a reported cause (BTS reports causes from June 2003).
Over time
On-time trend
By season
On-time rate by month
When to fly
Best time to fly ONT → ATL
All airlines · rolling 36 months (2023-06 .. 2026-05).
Best time of day
On-time rates are fairly even by time of day on this route — ranging from 86% to 91% on time.
- Mornings91% on time · p90 5 min · 1,087 flights
- Overnights91% on time · p90 5 min · 674 flights
- Middays86% on time · p90 20 min · 1,103 flights
Best day of week
On-time rates are fairly even by day on this route — ranging from 88% to 91% on time.
- Thursdays91% on time · p90 10 min · 428 flights
- Wednesdays91% on time · p90 10 min · 396 flights
- Tuesdays90% on time · p90 10 min · 391 flights
- Saturdays88% on time · p90 10 min · 368 flights
- Mondays88% on time · p90 15 min · 424 flights
- Fridays88% on time · p90 15 min · 429 flights
- Sundays88% on time · p90 10 min · 428 flights
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