Washington Dulles International in July 2025

69.2%departed on time

BTS: A flight is counted as on time if it arrived less than 15 minutes after its scheduled time. Only carriers with at least 0.5 percent of domestic scheduled passenger revenue report.

In July 2025, reporting carriers scheduled 5,248 domestic departures from Washington Dulles International (IAD). 69.2% left less than 15 minutes late and 67.2% reached their destination on time; 2.9% were cancelled.

Nationally that month, 69.7% of flights departed on time and 69.0% arrived on time, so IAD departures were 0.5 points below the national departure figure.

A year earlier, in July 2024, the airport had 4,692 departures with 74.4% leaving on time: a change of −5.2 points, with flights up 12%.

Flights arriving at IAD that month were on time 68.4% of the time (5,244 scheduled arrivals).

Of the delay minutes that carriers assigned to a BTS cause category that month, late-arriving aircraft 38%, air carrier 27% and national aviation system 18%.

On time 67.2%
Arrived 15+ minutes late 29.4%
Cancelled 2.9%
Diverted 0.5%

Every scheduled departure from IAD in July 2025, judged by arrival at the destination.

July 2025 against a year earlier, the airport's year and the nation

Measure	Jul 2025	Jul 2024	IAD, 12 months to Jul 2026	All reported flights, Jul 2025
Departed on time	69.2%	74.4%	82.6%	69.7%
Arrived on time	67.2%	73.0%	80.1%	69.0%
Cancelled	2.9%	2.2%	1.4%	2.5%
Average departure delay (late minutes only)	31.0 min	20.8 min	14.7 min	24.3 min
Scheduled departures a day	175	156	159	21,048
Scheduled departures	5,248	4,692	58,031	631,428

Airlines that month

Reporting carrier	Flights	Share	On time	Avg arrival delay	Cancelled
UA United Airlines	2,997	57%	68.9%	22.5 min	1.2%
YX Republic Airline	962	18%	67.4%	23.3 min	7.7%
DL Delta Air Lines	278	5%	70.5%	21.3 min	2.5%
AS Alaska Airlines	214	4%	57.9%	29.4 min	0.9%
OO SkyWest Airlines	209	4%	70.8%	25.9 min	1.4%
F9 Frontier Airlines	171	3%	48.5%	49.9 min	7.6%
OH PSA Airlines	143	3%	72.0%	13.3 min	5.6%
WN Southwest Airlines	115	2%	56.5%	22.5 min	3.5%
AA American Airlines	83	2%	59.0%	30.0 min	6.0%
G4 Allegiant Air	76	1%	60.5%	59.6 min	0.0%

Busiest routes that month

Route	Cities	Flights	On time	Avg arrival delay	Cancelled
IAD–DEN	Washington to Denver	361	65.7%	21.5 min	1.4%
IAD–ATL	Washington to Atlanta	353	65.2%	28.6 min	4.2%
IAD–SFO	Washington to San Francisco	267	67.8%	17.5 min	1.1%
IAD–SEA	Washington to Seattle	245	72.7%	14.3 min	0.8%
IAD–LAX	Washington to Los Angeles	224	58.9%	31.9 min	1.8%
IAD–ORD	Washington to Chicago	185	62.7%	30.3 min	1.6%
IAD–MCO	Washington to Orlando	176	68.2%	17.8 min	1.7%
IAD–DFW	Washington to Dallas/Fort Worth	173	63.0%	26.6 min	3.5%
IAD–TPA	Washington to Tampa	170	60.0%	26.4 min	1.8%
IAD–CLT	Washington to Charlotte	156	71.8%	13.2 min	6.4%
IAD–IAH	Washington to Houston	155	71.6%	16.6 min	0.6%
IAD–PIT	Washington to Pittsburgh	129	71.3%	23.8 min	6.2%

By scheduled departure hour

On-time share:under 62%6270768288% and over

Share of departures that left less than 15 minutes late, by scheduled hour (local time), July 2025.

Delay causes

BTS cause category	Share of delay minutes	National, Jul 2025	Minutes
Air carrier	26.9%	31.1%	42,526
Late-arriving aircraft	37.8%	40.8%	59,778
National Aviation System	18.3%	20.7%	29,010
Extreme weather	16.7%	7.3%	26,450
Security	0.3%	0.1%	445

158,209 delay minutes on 1,545 flights that arrived 15 or more minutes late and carried a cause report. Carriers assign the categories; see what each category means.

Questions and answers

How many flights left IAD on time in July 2025?

69.2% of 5,248 scheduled domestic departures left less than 15 minutes late, and 67.2% reached their destination on time. The national figures that month were 69.7% and 69.0%.

How does that compare with a year earlier?

In July 2024, 74.4% of 4,692 departures left on time and 2.2% were cancelled, against 69.2% and 2.9% in July 2025.

Provenance

Source: Bureau of Transportation Statistics, Reporting Carrier On-Time Performance, file for July 2025; public domain. Domestic scheduled flights by reporting carriers, totals and averages only. The site's data runs through July 2026. Full record for IAD · methodology · corrections.