OnTimeStats

Historical on-time performance

Chicago to San Francisco

1,846 miData through May 2026Source: US DOT · BTS

Flights on ORD–SFO arrive on time 69% of the time over the last 12 months.

On-time rate69%arrived within 15 min
p90 delay65 min1 in 10 flights is worse (tail risk)
Cancelled1.3%of scheduled flights

based on 5,588 flights over the last 12 months. On-time means arriving within 15 minutes (BTS standard).

By airline

How each carrier compares

  • United Airlinesbest
    On-time71%
    Medianon time
    p9060 min
    Cancel1.0%
    Flights3,772
  • American Airlines
    On-time65%
    Medianon time
    p9070 min
    Cancel1.8%
    Flights1,755
  • Alaska Airlines
    On-time59%
    Median5 min
    p9080 min
    Cancel3.3%
    Flights61

Why flights run late

Delay causes

  • Airline26%
  • Weather4%
  • Air traffic (NAS)28%
  • Late aircraft41%
  • Security0%

Most delay minutes here are attributed to Late aircraft.

When flights don't go

Why flights were cancelled

  • Airline41%
  • Weather55%
  • Air traffic (NAS)4%
  • Security0%

Most cancellations here are attributed to Weather. Shares are among 73 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 → SFO

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 — 82% on time.

  • Mornings82% on time · p90 30 min · 4,499 flights
  • Middays75% on time · p90 55 min · 3,152 flights
  • Afternoons74% on time · p90 60 min · 2,911 flights
  • Overnights62% on time · p90 75 min · 1,922 flights
  • Evenings60% on time · p90 75 min · 3,047 flights

Best day of week

On-time rates are fairly even by day on this route — ranging from 69% to 76% on time.

  • Tuesdays76% on time · p90 50 min · 2,111 flights
  • Saturdays75% on time · p90 50 min · 2,063 flights
  • Wednesdays72% on time · p90 55 min · 2,130 flights
  • Thursdays72% on time · p90 60 min · 2,313 flights
  • Mondays71% on time · p90 60 min · 2,291 flights
  • Sundays69% on time · p90 65 min · 2,310 flights
  • Fridays69% on time · p90 60 min · 2,313 flights

Keep exploring

Related pages

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.