OnTimeStats

Historical on-time performance

Chicago to Portland

1,739 miData through May 2026Source: US DOT · BTS

Flights on ORD–PDX arrive on time 70% of the time over the last 12 months.

On-time rate70%arrived within 15 min
p90 delay50 min1 in 10 flights is worse (tail risk)
Cancelled0.8%of scheduled flights

based on 2,648 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.

  • United Airlines
    On-time73%
    Medianon time
    p9045 min
    Cancel0.4%
    Flights1,386
  • Alaska Airlines
    On-time72%
    Medianon time
    p9035 min
    Cancel0.9%
    Flights462
  • American Airlines
    On-time64%
    Medianon time
    p9065 min
    Cancel1.4%
    Flights800

Why flights run late

Delay causes

  • Airline30%
  • Weather5%
  • Air traffic (NAS)18%
  • Late aircraft47%
  • Security0%

Most delay minutes here are attributed to Late aircraft.

When flights don't go

Why flights were cancelled

  • Airline24%
  • Weather71%
  • Air traffic (NAS)5%
  • Security0%

Most cancellations here are attributed to Weather. Shares are among 21 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 → PDX

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 · 2,080 flights
  • Middays80% on time · p90 35 min · 1,384 flights
  • Afternoons76% on time · p90 45 min · 1,991 flights
  • Evenings64% on time · p90 70 min · 488 flights
  • Overnights57% on time · p90 75 min · 1,112 flights

Best day of week

On-time rates are fairly even by day on this route — ranging from 72% to 77% on time.

  • Tuesdays77% on time · p90 45 min · 966 flights
  • Thursdays77% on time · p90 40 min · 1,043 flights
  • Saturdays77% on time · p90 40 min · 961 flights
  • Mondays76% on time · p90 45 min · 1,056 flights
  • Wednesdays75% on time · p90 50 min · 975 flights
  • Sundays72% on time · p90 50 min · 1,011 flights
  • Fridays72% on time · p90 55 min · 1,043 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.