OnTimeStats

Historical on-time performance

Boise to Salt Lake City

290 miData through May 2026Source: US DOT · BTS

Flights on BOI–SLC arrive on time 91% of the time over the last 12 months.

On-time rate91%arrived within 15 min
p90 delay10 min1 in 10 flights is worse (tail risk)
Cancelled0.9%of scheduled flights

based on 1,693 flights over the last 12 months. On-time means arriving within 15 minutes (BTS standard).

By airline

How each carrier compares

  • SkyWest Airlinesbest
    On-time95%
    Medianon time
    p90on time
    Cancel0.2%
    Flights459
  • Delta Air Lines
    On-time90%
    Medianon time
    p9010 min
    Cancel1.1%
    Flights1,234

Why flights run late

Delay causes

  • Airline57%
  • Weather4%
  • Air traffic (NAS)10%
  • Late aircraft29%
  • Security0%

Most delay minutes here are attributed to Airline.

When flights don't go

Why flights were cancelled

  • Airline80%
  • Weather13%
  • Air traffic (NAS)7%
  • Security0%

Most cancellations here are attributed to Airline. 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 BOI → SLC

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 87% to 90% on time.

  • Mornings90% on time · p90 10 min · 1,380 flights
  • Middays89% on time · p90 15 min · 2,166 flights
  • Evenings87% on time · p90 20 min · 1,494 flights

Best day of week

On-time rates are fairly even by day on this route — ranging from 86% to 91% on time.

  • Tuesdays91% on time · p90 5 min · 725 flights
  • Thursdays90% on time · p90 10 min · 733 flights
  • Saturdays89% on time · p90 15 min · 676 flights
  • Fridays89% on time · p90 15 min · 739 flights
  • Wednesdays88% on time · p90 15 min · 723 flights
  • Sundays88% on time · p90 20 min · 737 flights
  • Mondays86% on time · p90 20 min · 736 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.