IAD to STT flight delays & on-time performance
Nonstop flights from Washington Dulles International Airport to Cyril E. King Airport · 1,606 miles · Aug 2025 – Jul 2026
No FAA-reported ground stops or delays at IAD or STT right now. Individual flights can still be delayed by the airline; check with your airline for your flight.
Key facts
- Flights from Washington (IAD) to Charlotte Amalie (STT) arrived on time 88% of the time in Aug 2025 – Jul 2026, better than the 78% national average.
- 1.2% were cancelled, and 2% arrived an hour or more late.
- United Airlines is the only airline reporting nonstop flights on this route.
- Departures scheduled around 12pm did best (96% on time); around 8am did worst (87%).
- Tuesday was the most reliable day to fly (95% on time) and Friday the least (83%).
- The largest source of delay minutes was air traffic control & airport congestion (74%).
Which airline is most on time from IAD to STT?
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 | 88% | 1.2% | 5 min | 1.8% | 336 |
Best time of day to fly
On-time arrival rate by scheduled departure hour (local time).
- 8am87%297 flights
- 9am90%10 flights
- 12pm96%29 flights
Best day of the week
On-time arrival rate by day of departure.
- Monday89%0.0% cancelled
- Tuesday95%0.0% cancelled
- Wednesday89%0.0% cancelled
- Thursday91%0.0% cancelled
- Friday83%0.0% cancelled
- Saturday86%3.1% cancelled
- Sunday84%4.3% cancelled
On-time trend by month
Why flights are late
Share of delay minutes by cause, as reported by airlines to the DOT.
- Air traffic control & airport congestion74%
- Airline (crew, maintenance, cleaning, fueling)20%
- Late-arriving aircraft4%
- Extreme weather2%
- Security0%
Why flights are cancelled
Share of cancellations by reason.
- Extreme weather50%
- Air traffic control & airport congestion50%
- Airline (crew, maintenance, cleaning, fueling)0%
- Security0%
IAD to STT: common questions
- How often are IAD to STT flights on time?
- 88% 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 Washington to Charlotte Amalie cancelled?
- 1.2% of scheduled flights were cancelled (4 of 336).
- How long are typical delays?
- Across all flights the average arrival delay was 5 min (early arrivals count as zero). Flights that were late arrived 40 min behind schedule on average, and 1.8% of flights were an hour or more late.
- How long is taxi time at IAD?
- Flights on this route spent 20 min taxiing from the gate to takeoff on average.
Related routes
Return trip: STT to IAD — 82% on time
More flights from Washington
More flights to Charlotte Amalie
Data: U.S. DOT Bureau of Transportation Statistics, Aug 2025 – Jul 2026 (12 months). Latest month published by BTS: July 2026. Route: IAD → STT, nonstop flights by US airlines that report to the DOT. How we calculate this.