OnTimeStats

Historical on-time performance

Ontario to Salt Lake City

558 miData through May 2026Source: US DOT · BTS

Flights on ONT–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)
Cancelled1.1%of scheduled flights

based on 1,046 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.

  • SkyWest Airlines
    On-time94%
    Medianon time
    p905 min
    Cancel0.0%
    Flights140
  • Delta Air Lines
    On-time90%
    Medianon time
    p9010 min
    Cancel1.2%
    Flights906

Why flights run late

Delay causes

  • Airline44%
  • Weather4%
  • Air traffic (NAS)3%
  • Late aircraft48%
  • Security0%

Most delay minutes here are attributed to Late aircraft.

When flights don't go

Why flights were cancelled

  • Airline100%
  • Weather0%
  • Air traffic (NAS)0%
  • Security0%

Most cancellations here are attributed to Airline. Shares are among 11 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 ONT → 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 88% to 94% on time.

  • Mornings94% on time · p90 on time · 1,280 flights
  • Afternoons92% on time · p90 5 min · 207 flights
  • Evenings90% on time · p90 10 min · 944 flights
  • Middays88% on time · p90 20 min · 1,156 flights

Best day of week

On-time rates are fairly even by day on this route — ranging from 88% to 94% on time.

  • Tuesdays94% on time · p90 5 min · 508 flights
  • Fridays92% on time · p90 5 min · 526 flights
  • Wednesdays91% on time · p90 10 min · 510 flights
  • Thursdays90% on time · p90 10 min · 539 flights
  • Sundays89% on time · p90 10 min · 530 flights
  • Saturdays89% on time · p90 5 min · 455 flights
  • Mondays88% on time · p90 15 min · 519 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.