OnTimeStats

Historical on-time performance

San Juan to Houston

2,007 miData through May 2026Source: US DOT · BTS

Flights on SJU–IAH arrive on time 88% of the time over the last 12 months.

On-time rate88%arrived within 15 min
p90 delay15 min1 in 10 flights is worse (tail risk)
Cancelled0.7%of scheduled flights

based on 872 flights over the last 12 months. On-time means arriving within 15 minutes (BTS standard).

By airline

How each carrier compares

  • United Airlines
    On-time88%
    Medianon time
    p9015 min
    Cancel0.7%
    Flights872

Why flights run late

Delay causes

  • Airline28%
  • Weather0%
  • Air traffic (NAS)23%
  • Late aircraft49%
  • Security0%

Most delay minutes here are attributed to Late aircraft.

When flights don't go

Why flights were cancelled

  • Airline33%
  • Weather17%
  • Air traffic (NAS)50%
  • Security0%

Most cancellations here are attributed to Air traffic (NAS). Shares are among 6 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 → IAH

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

Best time of day

Early mornings are the most reliable time of day to fly this route — 97% on time.

  • Early mornings97% on time · p90 on time · 100 flights · limited
  • Mornings92% on time · p90 5 min · 1,048 flights
  • Middays86% on time · p90 20 min · 190 flights · limited
  • Afternoons73% on time · p90 45 min · 1,314 flights
  • Overnights66% on time · p90 85 min · 107 flights · limited

Best day of week

On-time rates are fairly even by day on this route — ranging from 78% to 84% on time.

  • Tuesdays84% on time · p90 20 min · 345 flights
  • Sundays83% on time · p90 30 min · 446 flights
  • Wednesdays82% on time · p90 30 min · 354 flights
  • Mondays82% on time · p90 25 min · 431 flights
  • Thursdays82% on time · p90 30 min · 362 flights
  • Fridays81% on time · p90 25 min · 367 flights
  • Saturdays78% on time · p90 40 min · 461 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.