OnTimeStats

Historical on-time performance

St. Thomas to San Juan

68 miData through May 2026Source: US DOT · BTS

Flights on STT–SJU arrive on time 70% of the time over the last 12 months.

On-time rate70%arrived within 15 min
p90 delay85 min1 in 10 flights is worse (tail risk)
Cancelled2.3%of scheduled flights

based on 477 flights over the last 12 months. On-time means arriving within 15 minutes (BTS standard).

By airline

How each carrier compares

  • JetBlue Airways
    On-time70%
    Medianon time
    p9085 min
    Cancel2.3%
    Flights477

Why flights run late

Delay causes

  • Airline16%
  • Weather1%
  • Air traffic (NAS)15%
  • Late aircraft67%
  • Security0%

Most delay minutes here are attributed to Late aircraft.

When flights don't go

Why flights were cancelled

  • Airline9%
  • Weather64%
  • Air traffic (NAS)27%
  • Security0%

Most cancellations here are attributed to Weather. 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 STT → SJU

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 67% to 70% on time.

  • Middays70% on time · p90 65 min · 624 flights
  • Evenings67% on time · p90 50 min · 158 flights · limited
  • Afternoons67% on time · p90 80 min · 1,086 flights

Best day of week

On-time rates are fairly even by day on this route — ranging from 61% to 78% on time.

  • Tuesdays78% on time · p90 50 min · 249 flights
  • Wednesdays73% on time · p90 70 min · 240 flights
  • Thursdays71% on time · p90 70 min · 271 flights
  • Sundays69% on time · p90 50 min · 257 flights
  • Fridays64% on time · p90 75 min · 241 flights
  • Saturdays62% on time · p90 90 min · 377 flights
  • Mondays61% on time · p90 85 min · 233 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.