SJU to IAD flight delays & on-time performance
Nonstop flights from Luis Munoz Marin International Airport to Washington Dulles International Airport · 1,572 miles · Aug 2025 – Jul 2026
No FAA-reported ground stops or delays at SJU or IAD right now. Individual flights can still be delayed by the airline; check with your airline for your flight.
Key facts
- Flights from San Juan (SJU) to Washington (IAD) arrived on time 87% of the time in Aug 2025 – Jul 2026, better than the 78% national average.
- 0.7% were cancelled, and 4% arrived an hour or more late.
- United Airlines was the most punctual airline here (90% on time); Frontier Airlines was the least (64%).
- Departures scheduled around 8am did best (95% on time); around 4pm did worst (78%).
- Wednesday was the most reliable day to fly (93% on time) and Saturday the least (83%).
- The largest source of delay minutes was late-arriving aircraft (39%).
Which airline is most on time from SJU to IAD?
Ranked by on-time arrival rate. Regional airlines fly under their partner's brand (e.g. SkyWest for Delta Connection or United Express).
| Airline | On time | Cancelled | Avg delay | 1 hr+ late | Flights |
|---|---|---|---|---|---|
| United Airlines | 90% | 0.6% | 6 min | 2.7% | 631 |
| Frontier Airlines | 64% | 1.3% | 37 min | 12.2% | 75 |
Best time of day to fly
On-time arrival rate by scheduled departure hour (local time).
- 6am100%14 flights
- 7am95%165 flights
- 8am95%127 flights
- 3pm79%14 flights
- 4pm78%258 flights
- 5pm87%126 flights
Best day of the week
On-time arrival rate by day of departure.
- Monday87%1.0% cancelled
- Tuesday90%0.0% cancelled
- Wednesday93%0.0% cancelled
- Thursday86%0.0% cancelled
- Friday88%0.0% cancelled
- Saturday83%2.8% cancelled
- Sunday84%0.9% cancelled
On-time trend by month
Why flights are late
Share of delay minutes by cause, as reported by airlines to the DOT.
- Late-arriving aircraft39%
- Airline (crew, maintenance, cleaning, fueling)39%
- Air traffic control & airport congestion21%
- Extreme weather1%
- Security0%
Why flights are cancelled
Share of cancellations by reason.
- Extreme weather60%
- Air traffic control & airport congestion40%
- Airline (crew, maintenance, cleaning, fueling)0%
- Security0%
SJU to IAD: common questions
- How often are SJU to IAD flights on time?
- 87% of flights arrived less than 15 minutes late in Aug 2025 – Jul 2026, compared with 78% for all US flights.
- How often are flights from San Juan to Washington cancelled?
- 0.7% of scheduled flights were cancelled (5 of 706).
- How long are typical delays?
- Across all flights the average arrival delay was 10 min (early arrivals count as zero). Flights that were late arrived 69 min behind schedule on average, and 3.7% of flights were an hour or more late.
- How long is taxi time at SJU?
- Flights on this route spent 16 min taxiing from the gate to takeoff on average.
Related routes
Return trip: IAD to SJU — 76% on time
More flights from San Juan
Data: U.S. DOT Bureau of Transportation Statistics, Aug 2025 – Jul 2026 (12 months). Latest month published by BTS: July 2026. Route: SJU → IAD, nonstop flights by US airlines that report to the DOT. How we calculate this.