OnTimeStats

Historical on-time performance

Boston to Salt Lake City

2,105 miData through Dec 2025Source: US DOT · BTS

Flights on BOS–SLC arrive on time 80% of the time over the last 12 months.

On-time rate80%arrived within 15 min
p90 delay35 min1 in 10 flights is worse (tail risk)
Cancelled0.4%of scheduled flights

based on 1,154 flights over the last 12 months. On-time means arriving within 15 minutes (BTS standard).

By airline

How each carrier compares

  • Delta Air Linesbest
    On-time81%
    Medianon time
    p9035 min
    Cancel0.3%
    Flights1,065
  • JetBlue Airways
    On-time67%
    Medianon time
    p9045 min
    Cancel2.2%
    Flights89

Why flights run late

Delay causes

  • Airline40%
  • Weather1%
  • Air traffic (NAS)27%
  • Late aircraft32%
  • Security0%

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 BOS → SLC

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 — 88% on time.

  • Mornings88% on time · p90 15 min · 1,289 flights
  • Middays82% on time · p90 30 min · 730 flights
  • Evenings71% on time · p90 60 min · 1,532 flights
  • Afternoons67% on time · p90 85 min · 280 flights

Best day of week

On-time rates are fairly even by day on this route — ranging from 75% to 81% on time.

  • Wednesdays81% on time · p90 30 min · 524 flights
  • Mondays80% on time · p90 40 min · 556 flights
  • Saturdays80% on time · p90 40 min · 578 flights
  • Tuesdays80% on time · p90 45 min · 527 flights
  • Thursdays78% on time · p90 40 min · 553 flights
  • Fridays76% on time · p90 45 min · 559 flights
  • Sundays75% on time · p90 45 min · 568 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.