OnTimeStats

Historical on-time performance

Los Angeles to Washington

2,288 miData through May 2026Source: US DOT · BTS

Flights on LAX–IAD arrive on time 85% of the time over the last 12 months.

On-time rate85%arrived within 15 min
p90 delay25 min1 in 10 flights is worse (tail risk)
Cancelled0.6%of scheduled flights

based on 2,386 flights over the last 12 months. On-time means arriving within 15 minutes (BTS standard).

By airline

How each carrier compares

Not enough comparable data to name a most-on-time carrier — low-data carriers aren't ranked.

  • United Airlines
    On-time85%
    Medianon time
    p9020 min
    Cancel0.7%
    Flights2,294
  • Alaska Airlines
    On-time79%
    Medianon time
    p9030 min
    Cancel0.0%
    Flights61
  • American Airlines
    On-time68%
    Medianon time
    p9060 min
    Cancel0.0%
    Flights31

Why flights run late

Delay causes

  • Airline35%
  • Weather0%
  • Air traffic (NAS)22%
  • Late aircraft43%
  • Security0%

Most delay minutes here are attributed to Late aircraft.

When flights don't go

Why flights were cancelled

  • Airline47%
  • Weather53%
  • Air traffic (NAS)0%
  • Security0%

Most cancellations here are attributed to Weather. Shares are among 15 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 LAX → IAD

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

Best time of day

Afternoons are the most reliable time of day to fly this route — 91% on time.

  • Afternoons91% on time · p90 10 min · 632 flights
  • Overnights86% on time · p90 20 min · 2,638 flights
  • Middays85% on time · p90 20 min · 2,357 flights
  • Mornings80% on time · p90 30 min · 1,835 flights

Best day of week

On-time rates are fairly even by day on this route — ranging from 82% to 87% on time.

  • Tuesdays87% on time · p90 15 min · 1,025 flights
  • Mondays86% on time · p90 20 min · 1,106 flights
  • Thursdays85% on time · p90 20 min · 1,115 flights
  • Wednesdays84% on time · p90 25 min · 1,053 flights
  • Fridays83% on time · p90 25 min · 1,109 flights
  • Sundays83% on time · p90 25 min · 1,119 flights
  • Saturdays82% on time · p90 30 min · 996 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.