OnTimeStats

Historical on-time performance

San Juan to St. Thomas

68 miData through May 2026Source: US DOT · BTS

Flights on SJU–STT arrive on time 74% of the time over the last 12 months.

On-time rate74%arrived within 15 min
p90 delay60 min1 in 10 flights is worse (tail risk)
Cancelled0.7%of scheduled flights

based on 277 flights over the last 12 months. On-time means arriving within 15 minutes (BTS standard).

By airline

How each carrier compares

  • JetBlue Airways
    On-time74%
    Medianon time
    p9060 min
    Cancel0.7%
    Flights277

Why flights run late

Delay causes

  • Airline33%
  • Weather5%
  • Air traffic (NAS)10%
  • Late aircraft52%
  • Security0%

Most delay minutes here are attributed to Late aircraft.

When flights don't go

Why flights were cancelled

  • Airline0%
  • Weather50%
  • Air traffic (NAS)50%
  • Security0%

Most cancellations here are attributed to Weather. Shares are among 2 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 SJU → STT

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

Best time of day

Middays are the most reliable time of day to fly this route — 78% on time.

  • Middays78% on time · p90 45 min · 736 flights
  • Afternoons65% on time · p90 75 min · 712 flights

Best day of week

On-time rates are fairly even by day on this route — ranging from 67% to 80% on time.

  • Tuesdays80% on time · p90 40 min · 200 flights
  • Sundays74% on time · p90 45 min · 221 flights
  • Thursdays72% on time · p90 65 min · 219 flights
  • Wednesdays72% on time · p90 60 min · 189 flights · limited
  • Fridays69% on time · p90 60 min · 212 flights
  • Mondays69% on time · p90 70 min · 208 flights
  • Saturdays67% on time · p90 80 min · 212 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.