Route reliability record
PIT→IAD
Pittsburgh to Washington
- Flights
- 1,210
- Period
- September 2025 to August 2026
- Distance
- 182 mi
- Carriers
- 2
This route earns an A. Close to nine flights in ten arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 11 points better than the national rate of 77.3%. When something does go wrong the average delay runs about an hour. That rests on 1,210 PIT to IAD flights, of which Republic Airways flew 693 at 89.4% on time.
Best time to fly PIT to IAD: a 5am–8am departure, ideally on a Saturday. Flights in that window arrived on time 96.9% of the time and Saturday flights 95.7%, against 87.9% for the route overall.
Set against the rest of the country, this route's record is 11 points better than the US average of 77.3%. That gap is worth roughly 106 fewer late arrivals for every thousand flights.
Key figures
On time
87.9%
Arrivals under 15 minutes late, of 1,193 completed flights
Avg delay
66 min
Across delayed arrivals only, not all flights
Cancelled
1.40%
National rate is 1.89%
Best carrier
Republic
89.4% on time across 693 flights
These figures cover 1,210 flights between September 2025 and August 2026. The median arrival is 11 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.
Fare search by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Carrier by carrier
Which airline is most reliable on PIT to IAD
The two carriers here are closely matched: 3 points separate the best from the worst. At that spread, schedule and price are better tie-breakers than reliability. Sample sizes are shown so you can see which rows are worth weighing.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Republic Airways | 693 | 89.4% | 55 min | 1.88% | A |
| United Airlines | 517 | 86.0% | 77 min | 0.77% | A+ |
No carrier stands out. Republic tops the table at 89.4%, 3 points clear of the bottom, which is inside the range this kind of sample moves year to year.
Flight by flight
Flights on PIT to IAD
The flight numbers below flew this route at least 250 times in the period, busiest first. Each has its own record, with its schedule and delay causes.
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Best ways to make this trip
The most reliable ways to fly Pittsburgh to Washington
Every airline on this route and on the routes between nearby airports, ranked by how often a scheduled flight actually operated and arrived on time. 3 of the top 5 use a different airport at one end.
| Option | Airline | Success | On time | Cancelled | Best departure | Most punctual flight |
|---|---|---|---|---|---|---|
| 1. PIT → IADPittsburgh to Washington | Republic Airways | 87.7% | 89.4% | 1.88% | 5am–8am, Sat | YX 3679 06:10 |
| 2. PIT → IADPittsburgh to Washington | United Airlines | 85.3% | 86.0% | 0.77% | 8am–11am, Sat | — |
| 3. PIT → BWIPittsburgh to Baltimore | Southwest Airlines | 84.5% | 85.7% | 1.40% | 8am–11am, Wed | — |
| 4. PIT → DCAPittsburgh to Washington | Republic Airways | 72.3% | 73.9% | 2.14% | 5am–8am, Sat | — |
| 5. PIT → DCAPittsburgh to Washington | PSA Airlines | 60.0% | 64.7% | 7.28% | 8am–11am, Sat | — |
Success is the share of scheduled flights that operated and arrived less than 15 minutes late, so a cancelled flight counts against it. “(route)” means the best time comes from every carrier on the route rather than this airline alone.
Departure window
The best time of day to leave
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 21 points, against 3 points between the best and worst carrier.
- 5am–8am360 flights96.9%
- 8am–11am238 flights92.8%
- 11am–2pm—
- 2pm–5pm285 flights76.2%
- 5pm–8pm—
- 8pm–5am327 flights84.5%
Scale runs 70% to 100%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 96.9% of the time, against 76.2% for the afternoon window. That is 21 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5am–8am window is the busiest, with 360 flights scheduled in it.
Explore
Filter PIT to IAD by airline, time, month and day
Pick a breakdown and a carrier. The dashed mark on each row is the same slice for every US flight.
On PIT to IAD, the best departure window is 5am–8am at 96.9% on time and the worst is 2pm–5pm at 76.2%, a wide gap of 20.7 points. All US flights leaving 5am–8am ran 89.3%.
- 5–8am96.9%
- 8–11am92.8%
- 11am–2pm—
- 2–5pm76.2%
- 5–8pm—
- 8pm–5am84.5%
best all US flightsScale 60% to 100%. Cells under 30 flights show a dash.
Across the year
When delays peak on this route
Twelve months, one bar each, drawn from the same 1,210 flights. The strip shows how much of this route's record is set by the calendar rather than by the operation.
August is the worst month at 80.9% on time, 12 points below January, the best at 92.5%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. March was the busiest month here, with 114 flights.
Across the week, Saturday is the strongest day at 95.7% on time and Sunday the weakest at 83.4%, a spread of 12 points.
Delay causes
Why this route gets delayed
Late-arriving aircraft accounts for 51% of the 9,532 delay minutes carriers reported here, and the remaining four split what is left.
- 51%Late-arriving aircraft
- 32%National Airspace System
- 16%Carrier
- 1%Extreme weather
51% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 9,532 reported delay minutes here, that single category outweighs weather by 36 to one. The split is drawn from 9,532 reported delay minutes.
The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 96.9% on time here.
Cancellations sit at 1.40% against a national 1.89%, which is ordinary. Diversions add another 0.00%.
Connections and stage length
What a delay here actually costs
Badly late arrivals are rare here: only 4.4% land an hour or more behind schedule, against 8.3% nationally. Connections built on this flight are about as safe as US domestic connections get, though a cancelled flight still ignores every layover you give it.
At 182 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 5am–8am window matters as much as it does.
The return leg is a different operation and performs like one: it runs 84.3% on time across 1,213 flights, 4 points below this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 4 points of difference.
The sample behind these figures is 1,210 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.
Work out the risk of missing a connection in IAD after this flight
What to do with this
Booking this route
Put together: take the 5am–8am departure, avoid August if the dates are flexible, and if two carriers are within a few dollars of each other, Republic is the one with the record behind it. None of that guarantees an on-time arrival; it moves the odds by 21 points, which is the most any booking decision can do. 1,193 completed flights over 12 months sit behind that.
Common questions
PIT to IAD questions
How often is PIT to IAD delayed?
About one flight in eight arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 12.1% of the 1,210 flights in this analysis, against 22.7% nationally. Delayed flights are late by about an hour on average.
Which airline is most reliable on PIT to IAD?
Republic Airways leads at 89.4% on time across 693 flights. United Airlines is at the other end on 86.0%, a gap of 3 points. Sample size matters as much as the percentage: a rate built from a few hundred flights moves around far more than one built from ten thousand.
What time of day has the fewest delays on PIT to IAD?
The 5am–8am departure window is the strongest at 96.9% on time. The 2pm–5pm window is the weakest at 76.2%, 21 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.
How bad are August delays on PIT to IAD?
August is the weakest month at 80.9% on time, compared with 92.5% in January. Across the year that is 12 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
- IAD to PIT — the return legseparate record
- Pittsburgh International (PIT) delay statistics
- Washington Dulles International (IAD) delay statistics
- Republic Airways on PIT to IAD89.4%
- United Airlines on PIT to IAD86.0%
- PIT to ORD, a related route77.1%
- ATL to IAD, a related route76.4%
- PIT to LGA, a related route79.9%
- Republic Airways on-time record89.4%
- United Airlines on-time record86.0%
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.05 million flight records
Direction matters. PIT to IAD and IAD to PIT are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Embed PIT to IAD’s on-time badge on your site
Paste this into a web page. The badge shows the current on-time rate, cancellation rate and grade, and updates every month. Preview it, or build a badge for another route or airport.
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.