IAD to PHL flight delays & on-time performance
Nonstop flights from Washington Dulles International Airport to Philadelphia International Airport · 135 miles · Aug 2025 – Jul 2026
No FAA-reported ground stops or delays at IAD or PHL 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 Philadelphia (PHL) arrived on time 82% of the time in Aug 2025 – Jul 2026, better than the 78% national average.
- 4.2% were cancelled, and 6% arrived an hour or more late.
- Republic Airways is the only airline reporting nonstop flights on this route.
- Departures scheduled around 12pm did best (86% on time); around 5pm did worst (74%).
- Wednesday was the most reliable day to fly (94% on time) and Saturday the least (67%).
- The largest source of delay minutes was air traffic control & airport congestion (43%).
Which airline is most on time from IAD to PHL?
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 |
|---|---|---|---|---|---|
| Republic AirwaysRegional airline operating flights for American Eagle, Delta Connection and United Express. | 82% | 4.2% | 13 min | 5.9% | 212 |
Best time of day to fly
On-time arrival rate by scheduled departure hour (local time).
- 8am83%69 flights
- 12pm86%37 flights
- 5pm74%37 flights
- 10pm82%69 flights
Best day of the week
On-time arrival rate by day of departure.
- Monday76%0.0% cancelled
- Tuesday83%6.5% cancelled
- Wednesday94%0.0% cancelled
- Thursday83%5.4% cancelled
- Friday82%9.7% cancelled
- Saturday67%7.7% cancelled
- Sunday81%3.1% 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 congestion43%
- Late-arriving aircraft30%
- Extreme weather14%
- Airline (crew, maintenance, cleaning, fueling)13%
- Security0%
Why flights are cancelled
Share of cancellations by reason.
- Air traffic control & airport congestion89%
- Extreme weather11%
- Airline (crew, maintenance, cleaning, fueling)0%
- Security0%
IAD to PHL: common questions
- How often are IAD to PHL flights on time?
- 82% 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 Philadelphia cancelled?
- 4.2% of scheduled flights were cancelled (9 of 212).
- How long are typical delays?
- Across all flights the average arrival delay was 13 min (early arrivals count as zero). Flights that were late arrived 68 min behind schedule on average, and 5.9% of flights were an hour or more late.
- How long is taxi time at IAD?
- Flights on this route spent 26 min taxiing from the gate to takeoff on average.
Related routes
Return trip: PHL to IAD — 87% on time
More flights from Washington
Data: U.S. DOT Bureau of Transportation Statistics, Aug 2025 – Jul 2026 (12 months). Latest month published by BTS: July 2026. Route: IAD → PHL, nonstop flights by US airlines that report to the DOT. How we calculate this.