OnTimeStats

Historical on-time performance

Seattle to San Diego

1,050 miData through May 2026Source: US DOT · BTS

Flights on SEA–SAN arrive on time 77% of the time over the last 12 months.

On-time rate77%arrived within 15 min
p90 delay30 min1 in 10 flights is worse (tail risk)
Cancelled1.2%of scheduled flights

based on 4,547 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-time82%
    Medianon time
    p9030 min
    Cancel0.9%
    Flights1,698
  • Alaska Airlines
    On-time74%
    Medianon time
    p9035 min
    Cancel1.5%
    Flights2,788
  • Southwest Airlines
    On-time59%
    Median10 min
    p9035 min
    Cancel0.0%
    Flights61

Why flights run late

Delay causes

  • Airline39%
  • Weather3%
  • Air traffic (NAS)29%
  • Late aircraft29%
  • Security0%

Most delay minutes here are attributed to Airline.

When flights don't go

Why flights were cancelled

  • Airline70%
  • Weather27%
  • Air traffic (NAS)4%
  • Security0%

Most cancellations here are attributed to Airline. Shares are among 56 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 SEA → SAN

All airlines · rolling 36 months (2023-06 .. 2026-05).

Best time of day

Mornings are the most reliable time of day to fly this route — 84% on time.

  • Mornings84% on time · p90 25 min · 4,508 flights
  • Middays79% on time · p90 30 min · 2,832 flights
  • Afternoons77% on time · p90 35 min · 2,686 flights
  • Overnights74% on time · p90 40 min · 912 flights
  • Evenings71% on time · p90 35 min · 2,890 flights

Best day of week

Tuesdays are the most reliable day to fly this route — 84% on time.

  • Tuesdays84% on time · p90 20 min · 1,907 flights
  • Wednesdays81% on time · p90 30 min · 1,882 flights
  • Saturdays80% on time · p90 30 min · 1,694 flights
  • Mondays78% on time · p90 30 min · 2,101 flights
  • Thursdays76% on time · p90 35 min · 2,112 flights
  • Sundays75% on time · p90 35 min · 2,045 flights
  • Fridays75% on time · p90 35 min · 2,087 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.