OnTimeStats

Historical on-time performance

Miami to Seattle

2,724 miData through Dec 2025Source: US DOT · BTS

Flights on MIA–SEA arrive on time 67% of the time over the last 12 months.

On-time rate67%arrived within 15 min
p90 delay60 min1 in 10 flights is worse (tail risk)
Cancelled0.7%of scheduled flights

based on 1,055 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.

  • Alaska Airlines
    On-time64%
    Medianon time
    p9055 min
    Cancel0.8%
    Flights363
  • American Airlines
    On-time72%
    Medianon time
    p9070 min
    Cancel0.0%
    Flights355
  • Delta Air Lines
    On-time65%
    Medianon time
    p9060 min
    Cancel1.2%
    Flights337

Why flights run late

Delay causes

  • Airline47%
  • Weather3%
  • Air traffic (NAS)19%
  • Late aircraft29%
  • Security2%

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 MIA → SEA

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 — 80% on time.

  • Mornings80% on time · p90 25 min · 103 flights · limited
  • Evenings68% on time · p90 60 min · 2,012 flights
  • Overnights60% on time · p90 80 min · 559 flights

Best day of week

On-time rates are fairly even by day on this route — ranging from 63% to 74% on time.

  • Tuesdays74% on time · p90 50 min · 379 flights
  • Wednesdays68% on time · p90 50 min · 379 flights
  • Fridays67% on time · p90 60 min · 382 flights
  • Saturdays67% on time · p90 75 min · 383 flights
  • Mondays65% on time · p90 60 min · 386 flights
  • Thursdays64% on time · p90 75 min · 382 flights
  • Sundays63% on time · p90 80 min · 387 flights
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Keep exploring

Related pages

Delay predictorfor this route→MIA airportMiami→SEA airportSeattle→Alaska Airlines on this routecarrier detail→Alaska Airlinesairline profile→

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.