OnTimeStats

Historical on-time performance

Newark to Seattle

2,401 miData through May 2026Source: US DOT · BTS

Flights on EWR–SEA arrive on time 71% of the time over the last 12 months.

On-time rate71%arrived within 15 min
p90 delay55 min1 in 10 flights is worse (tail risk)
Cancelled2.1%of scheduled flights

based on 2,179 flights over the last 12 months. On-time means arriving within 15 minutes (BTS standard).

By airline

How each carrier compares

  • United Airlinesbest
    On-time76%
    Medianon time
    p9050 min
    Cancel1.0%
    Flights972
  • Alaska Airlines
    On-time67%
    Medianon time
    p9055 min
    Cancel2.9%
    Flights1,207

Why flights run late

Delay causes

  • Airline18%
  • Weather8%
  • Air traffic (NAS)38%
  • Late aircraft35%
  • Security1%

Most delay minutes here are attributed to Air traffic (NAS).

When flights don't go

Why flights were cancelled

  • Airline24%
  • Weather60%
  • Air traffic (NAS)16%
  • Security0%

Most cancellations here are attributed to Weather. Shares are among 45 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 EWR → SEA

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 58% to 81% on time.

  • Middays81% on time · p90 35 min · 236 flights
  • Mornings81% on time · p90 30 min · 2,047 flights
  • Afternoons76% on time · p90 55 min · 1,454 flights
  • Evenings63% on time · p90 75 min · 2,224 flights
  • Overnights58% on time · p90 80 min · 175 flights · limited

Best day of week

On-time rates are fairly even by day on this route — ranging from 69% to 78% on time.

  • Tuesdays78% on time · p90 35 min · 864 flights
  • Wednesdays75% on time · p90 50 min · 863 flights
  • Mondays72% on time · p90 60 min · 894 flights
  • Thursdays71% on time · p90 55 min · 893 flights
  • Sundays71% on time · p90 60 min · 902 flights
  • Saturdays70% on time · p90 65 min · 819 flights
  • Fridays69% on time · p90 70 min · 901 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.