Airport month record

IADOCT

Washington Dulles International in October 2025

Departures: 4,854
Month: October 2025
National, same month: 79.7%
Carriers: 10

Historical statistics for October 2025, not live status or a forecast for this year’s October. For today’s conditions at IAD, see live FAA status.

IAD in October earns a B+. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 5 points better than the national rate of 79.7%. When something does go wrong the average delay runs about an hour. That rests on 4,854 flights, of which Republic Airways flew 785 at 86.6% on time.

Set against the rest of the country, IAD's October record is 5 points better than the US average of 79.7%. That gap is worth roughly 49 fewer late arrivals for every thousand flights.

On time

84.6%

Arrivals under 15 minutes late, of 4,832 completed departures

Avg delay

64 min

Across delayed arrivals only, not all flights

Cancelled

0.27%

Nationally in October: 0.53%

Whole year

81.1%

IAD across all twelve months

These figures cover 4,854 departures from Washington Dulles International in October 2025. 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

October next to IAD's other months

Against IAD's own year, October ran 4 points better than the twelve-month rate of 81.1%, which makes it number three of twelve months, best first. Cancellations were unusually low for IAD in October, at 0.27% against 1.37% across the year. Either side of it, September ran 86.8% on time and November 81.8%, so this month sits in line with its neighbours.

IAD month by month
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 (this page)	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	5,053	78.1%	85 min	0.93%	B+

Departure window

The best time of day to leave IAD in October

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 13 points, against 2 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am455 flights89.4%
8am–11am1,232 flights90.4%
11am–2pm900 flights85.8%
2pm–5pm234 flights82.8%
5pm–8pm1,396 flights77.7%
8pm–5am637 flights84.4%

Scale runs 70% to 95%. Rows with fewer than 30 flights show a dash.

Book the morning departure. Flights leaving between 8am–11am arrive on time 90.4% of the time, against 77.7% for the evening window. That is 13 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 1,396 flights scheduled in it.

Across the week, Wednesday is the strongest day at 87.8% on time and Sunday the weakest at 82.1%. 6 points is a smaller lever than departure hour, but it is free.

Carrier by carrier

Which airlines ran best at IAD in October

The two carriers here are closely matched: 2 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.

Carriers at IAD in October 2025
Airline	Flights	On time	Avg delay	Cancelled	Grade
United Airlines	3,007	84.8%	59 min	0.20%	B+
Republic Airways	785	86.6%	77 min	0.25%	A+
Delta Air Linesthin sample	256	82.3%	60 min	0.39%	B+
SkyWest Airlinesthin sample	223	90.1%	89 min	0.00%	A+
Frontier Airlinesthin sample	126	78.0%	99 min	1.59%	B
American Airlinesthin sample	120	81.7%	51 min	0.00%	B+
Alaska Airlinesthin sample	106	82.5%	50 min	1.89%	B
Southwest Airlinesthin sample	99	71.7%	35 min	0.00%	C+
PSA Airlinesthin sample	81	88.9%	84 min	0.00%	A+
Allegiant Airthin sample	51	82.4%	168 min	0.00%	B+

No carrier stands out. Republic tops the table at 86.6%, 2 points 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 October

Routes from IAD in October 2025
Route	Flights	On time	Avg delay	Cancelled	Grade
IAD to ATL · Atlantathin sample	334	81.6%	66 min	0.30%	B+
IAD to DEN · Denverthin sample	283	83.7%	39 min	0.00%	B+
IAD to SFO · San Franciscothin sample	246	82.8%	61 min	0.81%	B+
IAD to LAX · Los Angelesthin sample	202	89.6%	35 min	0.50%	A+
IAD to IAH · Houstonthin sample	180	82.2%	68 min	0.00%	B+
IAD to MCO · Orlandothin sample	177	83.1%	85 min	0.00%	B+
IAD to ORD · Chicagothin sample	176	72.7%	43 min	0.00%	C+
IAD to DFW · Dallas-Fort Worththin sample	173	83.6%	53 min	0.58%	B+
IAD to SEA · Seattlethin sample	156	84.4%	60 min	1.28%	B
IAD to CLT · Charlottethin sample	155	85.8%	80 min	0.00%	A+
IAD to EWR · Newarkthin sample	124	72.6%	102 min	0.00%	C+
IAD to BOS · Bostonthin sample	124	74.0%	81 min	0.81%	C+
IAD to RDU · Raleighthin sample	119	85.6%	44 min	0.00%	A+
IAD to SAN · San Diegothin sample	119	90.5%	23 min	0.00%	A+
IAD to CLE · Clevelandthin sample	112	91.1%	91 min	0.00%	A+
IAD to PIT · Pittsburghthin sample	111	90.1%	41 min	0.00%	A+
IAD to TPA · Tampathin sample	107	84.0%	40 min	0.93%	B+
IAD to PWM · Portlandthin sample	100	89.0%	45 min	0.00%	A+
IAD to LGA · New Yorkthin sample	99	77.6%	87 min	1.01%	B
IAD to CMH · Columbusthin sample	97	85.6%	63 min	0.00%	A+
IAD to PHX · Phoenixthin sample	97	75.3%	39 min	0.00%	B+
IAD to BDL · Hartfordthin sample	95	89.5%	34 min	0.00%	A+
IAD to BNA · Nashvillethin sample	93	82.8%	54 min	0.00%	B+
IAD to LAS · Las Vegasthin sample	93	87.1%	79 min	0.00%	A+
IAD to DTW · Detroitthin sample	89	93.3%	37 min	0.00%	A+

Delay causes

What held IAD up in October

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 48,000 reported delay minutes.

Late-arriving aircraft
39%
National Airspace System
31%
Carrier
28%
Extreme weather
1%
Security
0%

39% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 48,000 reported delay minutes here, that single category outweighs weather by 33 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 47,592 reported delay minutes.

Cancellations are rare at 0.27%, below the national 0.53% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.

Badly late arrivals are rare here: only 4.5% land an hour or more behind schedule, against 6.3% 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.

What to do with this

Flying from IAD in October

For a October trip through IAD: this is one of the better months to be flying from here, 84.6% on time with 0.27% cancelled. That is a base rate for the month as a whole; a single storm can still spoil a particular day.

Washington Dulles International (IAD), the whole year
IAD in July69.5%
IAD in August81.0%
IAD in September86.8%
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%
IAD in June78.1%

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.

Key figures