Route profile
ATL→IAD
Flight reliability, delays and best times to fly from Atlanta to Washington, 534 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 37% of comparable major US routes (4,598 compared)
Calculated from 11,307 flights. How this is calculated
ATL → IAD arrives on time 78.8% of the time; the return trip, IAD → ATL, arrives on time 80.0% of the time.
ATL → IAD spends 25.5 minutes on the ground on a 534-mile trip: 18.5 minutes from pushback to wheels-up at ATL and 7.0 minutes from touchdown to gate at IAD.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What stands out
This route has stayed remarkably steady year over year, a smaller swing than 100% of 5,368 comparable routes.
76.8% on time over the most recent 12 months (2025-08 to 2026-07), against 76.8% in the 12 months before (2024-08 to 2025-07), virtually unchanged.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Ranked against every other route with the same kind of figure and at least 5,368 in the comparison.
Why ATL → IAD flights are cancelled
July 2023 – July 2026
ATL → IAD cancelled 166 of 11,307 scheduled flights — about 1 in every 68. The reason filed most often was the airline, 58.4% of the cancellations coded on this route — about 1 in every 117 scheduled flights.
Share of cancellations
Of 166 cancelled departures carrying a reason code.
What each reason means
Crew, maintenance, aircraft cleaning, baggage or fueling: what BTS counts as within the carrier’s own control.
97 cancellations, 58.4% of the total.
Conditions the carrier judged severe enough to stop the flight: a blizzard, a hurricane, a line of thunderstorms.
64 cancellations, 38.6% of the total.
Airport capacity, air traffic control flow programs, heavy traffic and ordinary bad weather. A system decision, not the airline’s.
5 cancellations, 3.0% 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. Ordinary bad weather is filed under air traffic, so weather’s full share is larger than its bar.
166 coded cancellations were recorded on ATL → IAD; the section appears from 50.
When it goes wrong
July 2023 – July 2026
50 min late
against a median of 4 min early
Percentiles over 11,307 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at IAD after arriving from ATL.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 39% | Likely to miss |
| 45 min | 20% | High risk |
| 60 min | 14% | Some risk |
| 90 min | 8.4% | Some risk |
| 120 min | 5.4% | 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 1.47% 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 11,122 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 50 minutes late (90th-percentile gate arrival delay), over 11,307 operations.
Any other layover length: connection checker.
Best time to fly
ATL → IAD flights departing 5–9 AM arrived on time 90.1% of the time, against 69.1% for 9 PM–5 AM departures, a gap of 21.0 percentage points.
By departure window
By departure hour
- 12 AM to 4 AM: too few flights to score
- 5 AM: 96.0% on time from 482 flights
- 6 AM: too few flights to score
- 7 AM: 86.7% on time from 786 flights
- 8 AM: 90.0% on time from 325 flights
- 9 AM: 85.1% on time from 1,448 flights
- 10 AM: 85.6% on time from 674 flights
- 11 AM: 86.5% on time from 225 flights
- 12 PM: 81.2% on time from 623 flights
- 1 PM: 74.5% on time from 154 flights
- 2 PM: 75.3% on time from 1,851 flights
- 3 PM: 71.2% on time from 372 flights
- 4 PM: 70.7% on time from 519 flights
- 5 PM: 77.6% on time from 405 flights
- 6 PM: 77.8% on time from 219 flights
- 7 PM: 75.6% on time from 1,579 flights
- 8 PM: 73.2% on time from 187 flights
- 9 PM: 64.6% on time from 333 flights
- 10 PM: 69.9% on time from 1,074 flights
- 11 PM: too few flights to score
Why ATL → IAD runs late
July 2023 – July 2026
crew, maintenance, boarding and fueling, all within the carrier’s control
the inbound aircraft was late, so this flight started late
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 ATL → IAD. Only delays of 15 minutes or more are attributed.
How this route holds up in bad weather
July 2023 – July 2026
Bad weather raises cancellations by a similar amount at both ends of ATL to IAD: 3.3 times the normal rate at ATL and 3.1 times at IAD. Cancelled in bad weather against normal hours: ATL 3.4% against 1.0%, IAD 3.3% against 1.0%. Flights that did leave ATL in bad weather arrived on time 66.5% of the time, against 80.2% in normal hours.
Bad weather and normal hours at the airports
Scheduled departures, July 2023 – July 2026| Departures from | ATL | IAD |
|---|---|---|
| Cancelled in bad weather | 3.4% | 3.3% |
| Cancelled in normal hours | 1.0% | 1.0% |
| Arrived on time, bad weather | 66.5% | 69.1% |
| Arrived on time, normal hours | 80.2% | 82.7% |
| Departures in bad weather | 105,854 | 17,867 |
Of the carriers on this route, United Airlines (2.6% cancelled against 3.6% for the other carriers at ATL) cancelled the fewest departures from ATL in bad weather and Frontier Airlines (5.0% cancelled against 3.8% for the other carriers at ATL) the most.
This route’s airlines in bad weather at ATL
All departures from ATL| Airline | Bad-weather departures | Cancelled | Other carriers |
|---|---|---|---|
| United Airlines | 2,567 | 2.6%below the others | 3.6% |
| Delta Air Lines | 73,919 | 3.5%about level | 3.6% |
| Frontier Airlines | 4,928 | 5.0%above the others | 3.8% |
These are airport figures, not route figures: every scheduled departure from ATL and IAD, to any destination, in hours the weather report called bad. The airline rows count each carrier’s departures from ATL on every route.
Weather source and limits. In full: ATL (airlines), IAD, What Weather Costs Each Airport, Who Cancels More When the Weather Turns, Airports That Change Places When Weather Turns.
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 |
|---|---|---|---|---|---|
| Delta Air Lines | 6,570 | 79.2% | 1.57% | -3 min | 7.7% |
| United Airlines | 3,463 | 82.2% | 0.98% | -6 min | 7.4% |
| Frontier Airlines | 963 | 60.5% | 2.91% | 3 min | 20.1% |
Delta Air Lines flew 59.7% of the 10,996 flights listed. Frontier Airlines cancelled 2.91% of its flights here against 0.98% for United Airlines.
United Airlines arrived on time 21.7 percentage points more often than Frontier Airlines on this route.
Other ways to fly Atlanta to Washington
Airport pairs in the same two city markets, as the DOT defines them.
ATL → IAD is the most reliable pairing for this journey at 78.8% on time, against 73.7% for ATL → DCA.
Flights on this route
Flight numbers with at least 600 operations here and still on the schedule.
UA632 (9:25 AM) arrived on time 88.3% of the time, 15.4 points more often than DL1309 (7:25 PM) at 72.9%.
Weekly and seasonal patterns
By day of week
Wednesday is historically the most reliable day and Sunday the least, a gap of 7.9 percentage points.
By month
- Jan: 78.0%
- Feb: 83.9%
- Mar: 78.4%
- Apr: 80.9%
- May: 76.6%
- Jun: 74.4%
- Jul: 66.6%
- Aug: 77.5%
- Sep: 84.6%
- Oct: 87.3%
- Nov: 86.2%
- Dec: 78.1%
July is historically the weakest month and October the strongest, a spread of 20.7 percentage points.
Reliability over time
July 2023 – July 2026
- July 2023: 73.4% from 323 flights
- August 2023: 76.2% from 337 flights
- September 2023: 86.3% from 309 flights
- October 2023: 92.5% from 318 flights
- November 2023: 92.8% from 277 flights
- December 2023: 91.8% from 269 flights
- January 2024: 86.8% from 221 flights
- February 2024: 90.7% from 206 flights
- March 2024: 84.7% from 209 flights
- April 2024: 83.4% from 236 flights
- May 2024: 78.2% from 277 flights
- June 2024: 80.7% from 311 flights
- July 2024: 65.7% from 285 flights
- August 2024: 82.7% from 299 flights
- September 2024: 84.5% from 305 flights
- October 2024: 89.6% from 317 flights
- November 2024: 90.4% from 292 flights
- December 2024: 75.6% from 308 flights
- January 2025: 74.0% from 271 flights
- February 2025: 77.9% from 258 flights
- March 2025: 79.7% from 317 flights
- April 2025: 74.9% from 317 flights
- May 2025: 70.7% from 349 flights
- June 2025: 65.3% from 351 flights
- July 2025: 61.1% from 353 flights
- August 2025: 74.2% from 344 flights
- September 2025: 82.9% from 315 flights
- October 2025: 80.2% from 334 flights
- November 2025: 76.4% from 322 flights
- December 2025: 68.8% from 321 flights
- January 2026: 74.5% from 281 flights
- February 2026: 84.4% from 262 flights
- March 2026: 72.4% from 306 flights
- April 2026: 84.6% from 354 flights
- May 2026: 80.5% from 406 flights
- June 2026: 77.4% from 381 flights
- July 2026: 66.6% from 366 flights
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 76.8% against 76.8% in the 12 months before — broadly unchanged.
Data and methodology
Calculated by FlyerIntel from 11,307 ATL → 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