BTS DATA COMPLETE THROUGH JUNE 2026HISTORICAL ODDS · NOT LIVE FLIGHT STATUS
DelayOddsKnow the route before you book
IAD→SJU

Washington, DC (IAD) to San Juan, PR (SJU) flight delay odds

75.6% of 698 official scheduled IAD-to-SJU flights arrived on time; 15.0% arrived at least 30 minutes late and 0.7% were cancelled during July 2025–June 2026.

Source: U.S. Bureau of Transportation Statistics · Reporting window: July 2025–June 2026 · Updated September 16, 2026

HISTORICAL ROUTE SIGNALGenerally reliable
75.6%arrived on time
15.0%30+ min late
0.7%cancelled
698scheduled flights
Based on July 2025–June 2026; on time means arrival less than 15 minutes late.
60+ minutes late6.6%all scheduled flights
120+ minutes late3.0%all scheduled flights
Diverted0.1%did not reach as scheduled
Average arrival+15.1 mincompleted flights

Which departure time was most reliable for IAD to SJU?

Among qualifying IAD-to-SJU departure window results, Early morning had the highest on-time rate: 86.5% of 347 flights. Evening was lowest at 68.4% across 307 flights.

Departure windowFlightsOn time30+ minCancelled
Early morning34786.5%7.2%0.6%
Evening30768.4%19.9%0.7%

Which weekday was most reliable for IAD to SJU?

Among qualifying IAD-to-SJU weekday results, Wednesday had the highest on-time rate: 90.2% of 82 flights. Sunday was lowest at 67.8% across 118 flights.

DayFlightsOn time30+ minCancelled
Monday9576.8%14.7%0.0%
Tuesday9573.7%14.7%0.0%
Wednesday8290.2%6.1%0.0%
Thursday10274.5%17.6%0.0%
Friday9480.9%12.8%0.0%
Saturday11270.5%17.0%1.8%
Sunday11867.8%19.5%2.5%

Which airline was most reliable for IAD to SJU?

Among qualifying IAD-to-SJU airline results, United Airlines had the highest on-time rate: 80.3% of 609 flights. Frontier Airlines was lowest at 43.8% across 89 flights.

AirlineFlightsOn time30+ minCancelled
United Airlines60980.3%11.0%0.5%
Frontier Airlines8943.8%42.7%2.2%

Which month was most reliable for IAD to SJU?

Among qualifying IAD-to-SJU month results, May 2026 had the highest on-time rate: 93.5% of 62 flights. July 2025 was lowest at 58.5% across 53 flights.

MonthFlightsOn time30+ minCancelled
July 20255358.5%30.2%1.9%
August 20255070.0%20.0%0.0%
October 20254479.5%13.6%0.0%
November 20257368.5%21.9%0.0%
December 20257762.3%23.4%0.0%
January 20267474.3%8.1%5.4%
February 20266374.6%17.5%0.0%
March 20266779.1%14.9%0.0%
April 20266288.7%4.8%0.0%
May 20266293.5%6.5%0.0%
June 20266085.0%8.3%0.0%

What drove IAD to SJU delay minutes?

National airspace was the largest recorded IAD-to-SJU delay category, accounting for 34.0% of 15,218 BTS-attributed delay minutes during July 2025–June 2026.

Airline21.3%
Late aircraft30.0%
National airspace34.0%
Weather14.6%
Security0.0%
This is historical evidence, not a forecast.

Weather, schedules and operations change. For a trip you have already booked, use the airline or airport for live status.