OnTimeStats

Historical on-time performance

Boston to Los Angeles

2,611 miData through May 2026Source: US DOT · BTS

Flights on BOS–LAX arrive on time 75% of the time over the last 12 months.

On-time rate75%arrived within 15 min
p90 delay50 min1 in 10 flights is worse (tail risk)
Cancelled1.4%of scheduled flights

based on 4,655 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-time77%
    Medianon time
    p9045 min
    Cancel1.1%
    Flights716
  • JetBlue Airways
    On-time76%
    Medianon time
    p9050 min
    Cancel1.4%
    Flights1,622
  • Delta Air Lines
    On-time75%
    Medianon time
    p9040 min
    Cancel1.6%
    Flights1,224
  • American Airlines
    On-time72%
    Medianon time
    p9060 min
    Cancel1.3%
    Flights1,093

Why flights run late

Delay causes

  • Airline35%
  • Weather2%
  • Air traffic (NAS)20%
  • Late aircraft43%
  • Security0%

Most delay minutes here are attributed to Late aircraft.

When flights don't go

Why flights were cancelled

  • Airline29%
  • Weather68%
  • Air traffic (NAS)3%
  • Security0%

Most cancellations here are attributed to Weather. Shares are among 65 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 BOS → LAX

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 63% to 84% on time.

  • Mornings84% on time · p90 25 min · 5,514 flights
  • Middays83% on time · p90 25 min · 1,981 flights
  • Afternoons74% on time · p90 55 min · 1,315 flights
  • Evenings70% on time · p90 75 min · 3,598 flights
  • Overnights63% on time · p90 85 min · 1,402 flights

Best day of week

On-time rates are fairly even by day on this route — ranging from 74% to 81% on time.

  • Wednesdays81% on time · p90 35 min · 1,928 flights
  • Tuesdays79% on time · p90 35 min · 1,881 flights
  • Saturdays79% on time · p90 45 min · 1,721 flights
  • Thursdays77% on time · p90 50 min · 2,060 flights
  • Fridays76% on time · p90 55 min · 2,084 flights
  • Sundays75% on time · p90 60 min · 2,068 flights
  • Mondays74% on time · p90 55 min · 2,068 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.