Airport month record
IADJUN
Washington Dulles International in June 2026
- Departures
- 5,053
- Month
- June 2026
- National, same month
- 74.3%
- Carriers
- 9
Historical statistics for June 2026, not live status or a forecast for this year’s June. For today’s conditions at IAD, see live FAA status.
IAD in June lands a B+, 4 points better than the national rate of 74.3%. Roughly one flight in five arrives 15 minutes late or worse, and those flights are late by an hour and a half on average. That is a workable record, not a spotless one. That rests on 5,053 flights, of which Republic Airways flew 697 at 79.0% on time.
Key figures
On time
78.1%
Arrivals under 15 minutes late, of 4,989 completed departures
Avg delay
85 min
Across delayed arrivals only, not all flights
Cancelled
0.93%
Nationally in June: 1.65%
Whole year
81.1%
IAD across all twelve months
These figures cover 5,053 departures from Washington Dulles International in June 2026. On time means an arrival less than 15 minutes after the scheduled gate time, the DOT's threshold, and the national comparison uses every US departure in the same month rather than the whole year.
Against the year
June next to IAD's other months
Against IAD's own year, June ran 3 points worse than the twelve-month rate of 81.1%, which makes it number ten of twelve months, best first.
| Month | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| July 2025 | 5,248 | 69.5% | 102 min | 2.88% | C |
| August 2025 | 5,201 | 81.0% | 70 min | 0.79% | B+ |
| September 2025 | 4,815 | 86.8% | 67 min | 0.27% | A+ |
| October 2025 | 4,854 | 84.6% | 64 min | 0.27% | B+ |
| November 2025 | 4,589 | 81.8% | 71 min | 1.46% | B |
| December 2025 | 4,676 | 74.8% | 69 min | 0.71% | C+ |
| January 2026 | 4,248 | 83.0% | 82 min | 5.65% | B− |
| February 2026 | 4,037 | 83.3% | 74 min | 1.34% | B |
| March 2026 | 4,983 | 79.6% | 92 min | 1.81% | B |
| April 2026 | 4,843 | 87.2% | 71 min | 0.31% | A+ |
| May 2026 | 5,474 | 84.1% | 78 min | 0.57% | B+ |
| June 2026 (this page) | 5,053 | 78.1% | 85 min | 0.93% | B+ |
Departure window
The best time of day to leave IAD in June
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 21 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am483 flights85.3%
- 8am–11am1,216 flights87.8%
- 11am–2pm1,055 flights81.4%
- 2pm–5pm294 flights73.0%
- 5pm–8pm1,217 flights66.4%
- 8pm–5am788 flights74.1%
Scale runs 60% to 95%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 87.8% of the time, against 66.4% for the evening 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 5pm–8pm window is the busiest, with 1,217 flights scheduled in it.
Across the week, Tuesday is the strongest day at 84.4% on time and Friday the weakest at 74.1%. 10 points is a smaller lever than departure hour, but it is free.
Carrier by carrier
Which airlines ran best at IAD in June
The two carriers here are closely matched: half a point 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 |
|---|---|---|---|---|---|
| United Airlines | 3,162 | 78.9% | 79 min | 0.57% | B+ |
| Republic Airways | 697 | 79.0% | 95 min | 1.43% | B |
| Delta Air Linesthin sample | 300 | 81.4% | 72 min | 1.00% | B |
| SkyWest Airlinesthin sample | 239 | 82.1% | 117 min | 0.42% | B+ |
| Frontier Airlinesthin sample | 217 | 68.6% | 87 min | 3.23% | C− |
| American Airlinesthin sample | 180 | 70.7% | 98 min | 2.22% | C |
| Alaska Airlinesthin sample | 120 | 71.2% | 50 min | 1.67% | C |
| Allegiant Airthin sample | 70 | 54.3% | 127 min | 0.00% | F+ |
| PSA Airlinesthin sample | 59 | 86.0% | 228 min | 3.39% | A− |
No carrier stands out. Republic tops the table at 79.0%, half a point clear of the bottom, which is inside the range this kind of sample moves year to year.
Route by route
Busiest routes out of IAD in June
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| IAD to ATL · Atlanta | 381 | 76.9% | 81 min | 1.84% | B |
| IAD to DEN · Denverthin sample | 263 | 80.5% | 71 min | 0.00% | B+ |
| IAD to LAX · Los Angelesthin sample | 253 | 81.2% | 67 min | 1.19% | B |
| IAD to SFO · San Franciscothin sample | 234 | 63.5% | 49 min | 0.43% | D+ |
| IAD to ORD · Chicagothin sample | 210 | 79.4% | 116 min | 0.48% | B+ |
| IAD to SEA · Seattlethin sample | 198 | 78.5% | 72 min | 1.52% | B |
| IAD to DFW · Dallas-Fort Worththin sample | 196 | 66.7% | 128 min | 2.55% | C |
| IAD to IAH · Houstonthin sample | 180 | 78.0% | 79 min | 0.00% | B+ |
| IAD to MCO · Orlandothin sample | 169 | 79.5% | 56 min | 0.59% | B+ |
| IAD to EWR · Newarkthin sample | 150 | 78.9% | 70 min | 1.33% | B |
| IAD to DTW · Detroitthin sample | 120 | 83.8% | 75 min | 1.67% | B |
| IAD to SAN · San Diegothin sample | 120 | 75.0% | 58 min | 0.00% | B+ |
| IAD to BOS · Bostonthin sample | 120 | 81.2% | 62 min | 2.50% | B |
| IAD to CLT · Charlottethin sample | 119 | 80.2% | 134 min | 2.52% | B |
| IAD to CLE · Clevelandthin sample | 116 | 84.5% | 105 min | 0.00% | B+ |
| IAD to MSP · Minneapolisthin sample | 116 | 85.2% | 79 min | 0.86% | A+ |
| IAD to PWM · Portlandthin sample | 107 | 88.7% | 70 min | 0.93% | A+ |
| IAD to TPA · Tampathin sample | 95 | 82.1% | 95 min | 0.00% | B+ |
| IAD to BNA · Nashvillethin sample | 92 | 72.8% | 99 min | 0.00% | C+ |
| IAD to LAS · Las Vegasthin sample | 90 | 71.1% | 72 min | 0.00% | C+ |
| IAD to AUS · Austinthin sample | 88 | 73.6% | 71 min | 1.14% | C |
| IAD to PIT · Pittsburghthin sample | 86 | 76.5% | 97 min | 0.00% | B+ |
| IAD to RDU · Raleighthin sample | 86 | 78.6% | 81 min | 1.16% | B |
| IAD to IND · Indianapolisthin sample | 85 | 85.9% | 83 min | 0.00% | A+ |
| IAD to BDL · Hartfordthin sample | 85 | 83.1% | 76 min | 2.35% | B |
Delay causes
What held IAD up in June
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 93,000 reported delay minutes.
- 30%Late-arriving aircraft
- 30%National Airspace System
- 30%Carrier
- 10%Extreme weather
- 0%Security
The practical consequence: the 8am–11am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 87.8% on time here. The split is drawn from 93,194 reported delay minutes.
Cancellations sit at 0.93% against a national 1.65%, which is ordinary. Diversions add another 0.34%.
8.9% of arrivals land an hour or more late, close to the national 9.7%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last an hour and a half, which a normal layover absorbs.
What to do with this
Flying from IAD in June
For a June trip through IAD: plan on this being one of the airport's harder months. The 8am–11am departures held up best at 87.8% on time, and with 8.9% of arrivals an hour or more late, a connection here deserves more slack than the same trip in April would.
Related
Where to go next
- Washington Dulles International (IAD), the whole year
- IAD in July69.5%
- IAD in August81.0%
- IAD in September86.8%
- IAD in October84.6%
- IAD in November81.8%
- IAD in December74.8%
- IAD in January83.0%
- IAD in February83.3%
- IAD in March79.6%
- IAD in April87.2%
- IAD in May84.1%
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.