OnTimeStats

Historical on-time performance

Chicago to Atlanta

606 miData through May 2026Source: US DOT · BTS

Flights on ORD–ATL arrive on time 72% of the time over the last 12 months.

On-time rate72%arrived within 15 min
p90 delay60 min1 in 10 flights is worse (tail risk)
Cancelled2.2%of scheduled flights

based on 6,057 flights over the last 12 months. On-time means arriving within 15 minutes (BTS standard).

By airline

How each carrier compares

Too close to call — no single carrier is clearly more on-time here.

  • Delta Air Lines
    On-time77%
    Medianon time
    p9045 min
    Cancel2.3%
    Flights2,621
  • Envoy Air
    On-time76%
    Medianon time
    p9055 min
    Cancel2.5%
    Flights319
  • United Airlines
    On-time73%
    Medianon time
    p9050 min
    Cancel1.0%
    Flights1,575
  • Republic Airways
    On-time66%
    Medianon time
    p9085 min
    Cancel5.1%
    Flights178
  • Frontier Airlines
    On-time63%
    Medianon time
    p9080 min
    Cancel3.4%
    Flights709
  • American Airlines
    On-time61%
    Medianon time
    p90100 min
    Cancel2.4%
    Flights625
  • Spirit Airlines
    On-time37%
    Median15 min
    p9065 min
    Cancel0.0%
    Flights30

Why flights run late

Delay causes

  • Airline27%
  • Weather4%
  • Air traffic (NAS)20%
  • Late aircraft48%
  • Security0%

Most delay minutes here are attributed to Late aircraft.

When flights don't go

Why flights were cancelled

  • Airline39%
  • Weather49%
  • Air traffic (NAS)12%
  • Security0%

Most cancellations here are attributed to Weather. Shares are among 132 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 ORD → ATL

All airlines · rolling 36 months (2023-06 .. 2026-05).

Best time of day

Mornings are the most reliable time of day to fly this route — 83% on time.

  • Mornings83% on time · p90 25 min · 6,292 flights
  • Middays78% on time · p90 45 min · 3,627 flights
  • Afternoons72% on time · p90 55 min · 3,085 flights
  • Evenings63% on time · p90 85 min · 3,986 flights
  • Overnights61% on time · p90 95 min · 945 flights

Best day of week

On-time rates are fairly even by day on this route — ranging from 71% to 78% on time.

  • Wednesdays78% on time · p90 50 min · 2,525 flights
  • Saturdays76% on time · p90 50 min · 2,276 flights
  • Tuesdays76% on time · p90 50 min · 2,460 flights
  • Thursdays75% on time · p90 50 min · 2,668 flights
  • Mondays74% on time · p90 55 min · 2,683 flights
  • Fridays72% on time · p90 55 min · 2,710 flights
  • Sundays71% on time · p90 65 min · 2,615 flights

Keep exploring

Related pages

Delay predictorfor this route→ORD airportChicago→ATL airportAtlanta→Delta Air Linesairline profile→United Airlinesairline profile→Frontier Airlinesairline profile→Seasonal delay patternsguide→

Methodology

A flight is on time when it arrives within 15 minutes of schedule — the US DOT / BTS standard. Median and p90(the “1-in-10 bad day”) are read from the full arrival-delay distribution, never averaged across periods.

Figures cover a carrier’s own BTS-coded flights. Cells below ~200 flights are flagged as limited data. All numbers are pre-computed from public BTS On-Time Performance data.