OnTimeStats

Historical on-time performance

Seattle to Boise

399 miData through Dec 2025Source: US DOT · BTS

Flights on SEA–BOI arrive on time 82% of the time over the last 12 months.

On-time rate82%arrived within 15 min
p90 delay25 min1 in 10 flights is worse (tail risk)
Cancelled0.2%of scheduled flights

based on 3,954 flights over the last 12 months. On-time means arriving within 15 minutes (BTS standard).

By airline

How each carrier compares

  • SkyWest Airlinesbest
    On-time85%
    Medianon time
    p9020 min
    Cancel0.1%
    Flights3,222
  • Alaska Airlines
    On-time69%
    Medianon time
    p9035 min
    Cancel0.8%
    Flights732

Why flights run late

Delay causes

  • Airline42%
  • Weather15%
  • Air traffic (NAS)15%
  • Late aircraft28%
  • Security1%

Most delay minutes here are attributed to Airline.

Over time

On-time trend

By season

On-time rate by month

When to fly

Best time to fly SEA → BOI

All airlines · rolling 36 months (2023-01 .. 2025-12).

Best time of day

Mornings are the most reliable time of day to fly this route — 89% on time.

  • Mornings89% on time · p90 15 min · 2,046 flights
  • Afternoons86% on time · p90 20 min · 1,717 flights
  • Evenings83% on time · p90 25 min · 2,988 flights
  • Middays82% on time · p90 25 min · 3,681 flights
  • Overnights81% on time · p90 30 min · 1,810 flights

Best day of week

On-time rates are fairly even by day on this route — ranging from 81% to 87% on time.

  • Tuesdays87% on time · p90 15 min · 1,714 flights
  • Saturdays87% on time · p90 20 min · 1,642 flights
  • Wednesdays87% on time · p90 20 min · 1,727 flights
  • Mondays83% on time · p90 25 min · 1,800 flights
  • Fridays82% on time · p90 25 min · 1,783 flights
  • Sundays82% on time · p90 25 min · 1,786 flights
  • Thursdays81% on time · p90 25 min · 1,790 flights
Advertisement

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.