Route profile
ORD→IAD
Flight reliability, delays and best times to fly from Chicago to Washington, 588 miles.
Right now
Aviation weather is not currently a factor.
Aviation weather is not currently a factor.
Route reliability
July 2023 – July 2026
Better than 41% of comparable major US routes (4,598 compared)
Calculated from 5,761 flights. How this is calculated · What counts as on time
ORD → IAD arrives on time 77.0% of the time; the return trip, IAD → ORD, arrives on time 78.2% of the time.
ORD → IAD spends 33.6 minutes on the ground on a 588-mile trip: 25.8 minutes from pushback to wheels-up at ORD and 7.8 minutes from touchdown to gate at IAD.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What sets this route apart
Where ORD to IAD differs most from similar routes by hour, weekday, month and airline, July 2023 – July 2026.
ORD to IAD struggles most at 5 PM: 53.5% of its flights scheduled then arrive on time, 17.1 points behind the 70.6% on routes of similar length at the same hour. Against all other routes the gap is 16.3 points.
ORD to IAD is at its best against routes of similar length for flights scheduled at 3 PM: 82.9% arrive on time, 8.8 points ahead of the 74.1% those routes manage at that hour. Against all other routes the gap is 10.2 points.
Wednesday is the day ORD to IAD slips furthest against routes of similar length, 76.6% on time where they average 81.7%, 5.1 points lower. Against all other routes the gap is 4.2 points.
In March, ORD to IAD runs 4.7 points below routes of similar length, 74.0% on time to 78.7%.
United Airlines’ flights on ORD to IAD arrive on time 77.0% of the time, 2.1 points below the 79.1% it manages on its routes of similar length. Against all other routes the gap is 2.9 points.
ORD to IAD against comparable routes
July 2023 – July 2026| Measure | This route | Compared with | Them | Gap | Flights behind it |
|---|---|---|---|---|---|
| Hour: 5 PM departures | 53.5% | routes of similar length | 70.6% | −17.1 pts | 441 here, 127,613 there |
| Hour: 3 PM departures | 82.9% | routes of similar length | 74.1% | +8.8 pts | 228 here, 114,946 there |
| Weekday: Wednesday | 76.6% | routes of similar length | 81.7% | −5.1 pts | 820 here, 274,272 there |
| Month: March | 74.0% | routes of similar length | 78.7% | −4.7 pts | 420 here, 160,914 there |
| Airline: United Airlines | 77.0% | routes of similar length | 79.1% | −2.1 pts | 5,701 here, 171,851 there |
Each comparison pools the flights of other routes, with this route’s own left out. Similar length means within 15% of this route’s 588 miles, with at least 5 such routes. A bucket is set against the most comparable group that has enough flights: similar length, then the same origin (at least 3 routes), then all other routes. Hours, weekdays and months appear only where both sides have 120 completed flights, and airlines where both have 600. The gap must be at least 2 points and 2 standard errors, and only the largest gap each way is kept per measure. These are differences in the flights counted, not causes.
Why ORD → IAD flights are cancelled
July 2023 – July 2026
ORD → IAD cancelled 50 of 5,761 scheduled flights — about 1 in every 115. The reason filed most often was extreme weather, 62.0% of the cancellations coded on this route — about 1 in every 186 scheduled flights.
Share of cancellations
Of 50 cancelled departures carrying a reason code.
What each reason means
Conditions the carrier judged severe enough to stop the flight: a blizzard, a hurricane, a line of thunderstorms.
31 cancellations, 62.0% of the total.
Crew, maintenance, aircraft cleaning, baggage or fueling: what BTS counts as within the carrier’s own control.
17 cancellations, 34.0% of the total.
Airport capacity, air traffic control flow programs, heavy traffic and ordinary bad weather. A system decision, not the airline’s.
2 cancellations, 4.0% of the total.
A terminal evacuation, a security breach, screening equipment failure, or screening queues over 29 minutes.
0 cancellations, 0.0% of the total.
Reason codes are the operating airline’s own filing with US DOT, not an independent finding of fault. With only one or two carriers on the route, the split mostly reflects how they file. Ordinary bad weather is filed under air traffic, so weather’s full share is larger than its bar.
50 coded cancellations were recorded on ORD → IAD; the section appears from 50.
When it goes wrong
July 2023 – July 2026
48 min late
against a median of 3 min early
Percentiles over 5,761 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at IAD after arriving from ORD.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 42% | Likely to miss |
| 45 min | 22% | High risk |
| 60 min | 14% | Some risk |
| 90 min | 8.1% | Some risk |
| 120 min | 5.6% | Some risk |
This is one leg of a connection. Gate changes and the next flight's own schedule matter too. And a connection can fail before delay is even the question — this route cancels 0.87% of the time and diverts 0.17% of the time, which a late arrival never shows up in.
Chance of missing is the share of 5,701 arrivals on this route that landed later than the connection time less 30 minutes to reach the next gate.
The worst tenth of arrivals on this route land at least 48 minutes late (90th-percentile gate arrival delay), over 5,761 operations.
Any other layover length: connection checker.
Best time to fly
ORD → IAD flights departing 5–9 AM arrived on time 87.1% of the time, against 64.7% for 3–6 PM departures, a gap of 22.4 percentage points.
By departure window
By departure hour
- 12 AM to 6 AM: too few flights to score
- 7 AM: 91.2% on time from 219 flights
- 8 AM: 85.4% on time from 1,107 flights
- 9 AM: too few flights to score
- 10 AM: 82.7% on time from 173 flights
- 11 AM: 90.5% on time from 211 flights
- 12 PM: 83.6% on time from 128 flights
- 1 PM: 78.8% on time from 1,001 flights
- 2 PM: 68.4% on time from 402 flights
- 3 PM: 82.9% on time from 231 flights
- 4 PM: 69.9% on time from 148 flights
- 5 PM: 53.5% on time from 451 flights
- 6 PM: 71.5% on time from 673 flights
- 7 PM to 8 PM: too few flights to score
- 9 PM: 73.1% on time from 920 flights
- 10 PM to 11 PM: too few flights to score
Why ORD → IAD runs late
July 2023 – July 2026
the inbound aircraft was late, so this flight started late
crew, maintenance, boarding and fueling, all within the carrier’s control
airspace and airport capacity, including weather-driven flow control
weather severe enough to stop this flight specifically
Share of the delay minutes US DOT attributed to each cause for ORD → IAD. Only delays of 15 minutes or more are attributed. What the five causes mean
Late-arriving aircraft is the largest cause on ORD → IAD, at 37.4%: flights here mostly leave late because the plane came in late, and the day shows it: 5–9 AM departures arrived on time 87.1% of the time and 3–6 PM departures 64.7%.
Airlines on this route
Carriers with at least 200 flights, by the airline that operated each one.
| Carrier | Flights | On time | Cancelled | Median delay | Severe |
|---|---|---|---|---|---|
| United Airlines | 5,761 | 77.0% | 0.87% | -3 min | 8.3% |
Other ways to fly Chicago to Washington
Airport pairs in the same two city markets, as the DOT defines them.
| Route | Flights | On time | Cancelled | Median delay | Score |
|---|---|---|---|---|---|
| ORD→DCA Chicago to Washington | 20,159 | 73.0% | 2.28% | -3 min | 46 |
| ORD→IAD this route Chicago to Washington | 5,761 | 77.0% | 0.87% | -3 min | 62 |
ORD → IAD is the most reliable pairing for this journey at 77.0% on time, against 73.0% for ORD → DCA.
Flying to IAD from the Chicago area? Compare ORD, MDW for IAD, with the same test for what counts as a real difference.
Weekly and seasonal patterns
By day of week
Tuesday is historically the most reliable day and Sunday the least, a gap of 5.8 percentage points.
By month
- Jan: 75.8%
- Feb: 82.4%
- Mar: 74.0%
- Apr: 81.4%
- May: 75.9%
- Jun: 74.7%
- Jul: 67.5%
- Aug: 73.8%
- Sep: 82.0%
- Oct: 83.4%
- Nov: 82.3%
- Dec: 76.1%
July is historically the weakest month and October the strongest, a spread of 15.9 percentage points.
Reliability over time
July 2023 – July 2026
- July 2023: 60.8% from 150 flights
- August 2023: 82.9% from 160 flights
- September 2023: 75.9% from 162 flights
- October 2023: 84.3% from 160 flights
- November 2023: 88.4% from 121 flights
- December 2023: 82.8% from 122 flights
- January 2024: 70.2% from 124 flights
- February 2024: too few flights to score (117)
- March 2024: 81.5% from 124 flights
- April 2024: 81.8% from 121 flights
- May 2024: 75.3% from 154 flights
- June 2024: 74.0% from 151 flights
- July 2024: 70.2% from 155 flights
- August 2024: 68.0% from 155 flights
- September 2024: 88.1% from 151 flights
- October 2024: 92.4% from 157 flights
- November 2024: 88.6% from 149 flights
- December 2024: 77.2% from 127 flights
- January 2025: 82.0% from 124 flights
- February 2025: too few flights to score (112)
- March 2025: 75.5% from 152 flights
- April 2025: 85.9% from 180 flights
- May 2025: 73.0% from 186 flights
- June 2025: 65.2% from 180 flights
- July 2025: 58.0% from 185 flights
- August 2025: 70.8% from 196 flights
- September 2025: 82.1% from 201 flights
- October 2025: 74.6% from 177 flights
- November 2025: 70.9% from 151 flights
- December 2025: 69.7% from 145 flights
- January 2026: 75.2% from 129 flights
- February 2026: too few flights to score (112)
- March 2026: 66.2% from 148 flights
- April 2026: 76.8% from 181 flights
- May 2026: 78.7% from 216 flights
- June 2026: 83.3% from 210 flights
- July 2026: 78.2% from 216 flights
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 75.9% against 77.4% in the 12 months before — declining by 1.5 percentage points.
Data and methodology
Calculated by FlyerIntel from 5,761 ORD → IAD flight records from the US DOT Bureau of Transportation Statistics, covering July 2023 – July 2026. Late means 15 or more minutes past scheduled arrival; cancelled and diverted flights are left out of on-time rates.
Full methodology · Data sources · Report a problem
Related research: How Long a Layover Needs to Be · Two Airlines on One Route · Best Time of Day to Fly From Major US Airports
Analysis last recomputed