OnTimeStats

Historical on-time performance

Seattle to Detroit

1,927 miData through Dec 2025Source: US DOT · BTS

Flights on SEA–DTW arrive on time 83% of the time over the last 12 months.

On-time rate83%arrived within 15 min
p90 delay25 min1 in 10 flights is worse (tail risk)
Cancelled0.5%of scheduled flights

based on 1,979 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-time85%
    Medianon time
    p9020 min
    Cancel0.7%
    Flights1,507
  • Alaska Airlines
    On-time78%
    Medianon time
    p9025 min
    Cancel0.0%
    Flights472

Why flights run late

Delay causes

  • Airline49%
  • Weather0%
  • Air traffic (NAS)18%
  • Late aircraft33%
  • 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 SEA → DTW

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

Best time of day

On-time rates are fairly even by time of day on this route — ranging from 79% to 88% on time.

  • Mornings88% on time · p90 15 min · 2,139 flights
  • Afternoons87% on time · p90 15 min · 735 flights
  • Middays80% on time · p90 25 min · 1,657 flights
  • Overnights79% on time · p90 25 min · 1,599 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 · 829 flights
  • Wednesdays86% on time · p90 20 min · 848 flights
  • Saturdays85% on time · p90 20 min · 800 flights
  • Thursdays83% on time · p90 25 min · 904 flights
  • Mondays83% on time · p90 25 min · 924 flights
  • Fridays82% on time · p90 25 min · 926 flights
  • Sundays81% on time · p90 30 min · 919 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.