Route profile
RDU→ORD
Flight reliability, delays and best times to fly from Raleigh–Durham to Chicago, 646 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 31% of comparable major US routes (4,598 compared)
Calculated from 10,064 flights. How this is calculated
RDU → ORD arrives on time 78.9% of the time; the return trip, ORD → RDU, arrives on time 76.8% of the time, a 2.0-point gap between the two directions of the same city pair.
RDU → ORD spends 36.9 minutes on the ground on a 646-mile trip: 19.3 minutes from pushback to wheels-up at RDU and 17.7 minutes from touchdown to gate at ORD.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What stands out
The airline matters unusually much on this route, a wider carrier-to-carrier gap than 99% of 2,692 comparable routes.
American Airlines arrived on time 85.0% of the time, against 55.4% for Frontier Airlines, flying the exact same route.
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 2,692 in the comparison.
Why RDU → ORD flights are cancelled
July 2023 – July 2026
RDU → ORD cancelled 185 of 10,064 scheduled flights — about 1 in every 54. The reason filed most often was extreme weather, 69.2% of the cancellations coded on this route — about 1 in every 79 scheduled flights.
Share of cancellations
Of 185 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.
128 cancellations, 69.2% of the total.
Airport capacity, air traffic control flow programs, heavy traffic and ordinary bad weather. A system decision, not the airline’s.
32 cancellations, 17.3% of the total.
Crew, maintenance, aircraft cleaning, baggage or fueling: what BTS counts as within the carrier’s own control.
25 cancellations, 13.5% 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.
185 coded cancellations were recorded on RDU → ORD; the section appears from 50.
When it goes wrong
July 2023 – July 2026
49 min late
against a median of 8 min early
Percentiles over 10,064 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at ORD after arriving from RDU.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 35% | Likely to miss |
| 45 min | 20% | High risk |
| 60 min | 14% | Some risk |
| 90 min | 8.5% | Some risk |
| 120 min | 5.7% | 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 1.84% of the time and diverts 0.33% of the time, which a late arrival never shows up in.
Chance of missing is the share of 9,846 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 49 minutes late (90th-percentile gate arrival delay), over 10,064 operations.
Any other layover length: connection checker.
Best time to fly
RDU → ORD flights departing 9 AM–12 PM arrived on time 88.1% of the time, against 66.8% for 3–6 PM departures, a gap of 21.3 percentage points.
By departure window
By departure hour
- 12 AM to 4 AM: too few flights to score
- 5 AM: 92.6% on time from 140 flights
- 6 AM: 90.6% on time from 1,629 flights
- 7 AM: 83.4% on time from 912 flights
- 8 AM: 82.6% on time from 294 flights
- 9 AM: 85.9% on time from 589 flights
- 10 AM: 89.7% on time from 988 flights
- 11 AM: 86.6% on time from 166 flights
- 12 PM: 84.4% on time from 353 flights
- 1 PM: 80.4% on time from 1,004 flights
- 2 PM: 73.8% on time from 323 flights
- 3 PM: 75.4% on time from 650 flights
- 4 PM: 74.7% on time from 826 flights
- 5 PM: 57.4% on time from 1,278 flights
- 6 PM: 69.4% on time from 613 flights
- 7 PM: 60.6% on time from 217 flights
- 8 PM to 11 PM: too few flights to score
Departure windows with fewer than 120 flights are not scored.
Why RDU → ORD runs late
July 2023 – July 2026
the inbound aircraft was late, so this flight started late
airspace and airport capacity, including weather-driven flow control
crew, maintenance, boarding and fueling, all within the carrier’s control
weather severe enough to stop this flight specifically
screening or terminal security incidents
Share of the delay minutes US DOT attributed to each cause for RDU → ORD. Only delays of 15 minutes or more are attributed.
Late-arriving aircraft is the largest cause on RDU → ORD, at 36.0%: flights here mostly leave late because the plane came in late, and the day shows it: 9 AM–12 PM departures arrived on time 88.1% of the time and 3–6 PM departures 66.8%.
How this route holds up in bad weather
July 2023 – July 2026
The harder-hit end is ORD, where the flight lands. Its figure counts departures from ORD, so it says more about how that airport copes than about this route. Bad weather cancels 5.5 times the normal rate at ORD against 2.6 times at RDU. Cancelled in bad weather against normal hours: RDU 4.1% against 1.6%, ORD 6.5% against 1.2%. Flights that did leave ORD in bad weather arrived on time 55.7% of the time, against 77.1% in normal hours.
Bad weather and normal hours at the airports
Scheduled departures, July 2023 – July 2026| Departures from | RDU | ORD |
|---|---|---|
| Cancelled in bad weather | 4.1% | 6.5% |
| Cancelled in normal hours | 1.6% | 1.2% |
| Arrived on time, bad weather | 74.9% | 55.7% |
| Arrived on time, normal hours | 79.9% | 77.1% |
| Departures in bad weather | 16,672 | 104,455 |
Of the carriers on this route, United Airlines (2.7% cancelled against 4.4% for the other carriers at RDU) cancelled the fewest departures from RDU in bad weather and Republic Airways (7.8% cancelled against 4.4% for the other carriers at RDU) the most. 2 more carriers fly this route but has too few bad-weather departures from RDU to compare.
This route’s airlines in bad weather at RDU
All departures from RDU| Airline | Bad-weather departures | Cancelled | Other carriers |
|---|---|---|---|
| United Airlines | 1,776 | 2.7%below the others | 4.4% |
| American Airlines | 3,228 | 4.0%about level | 3.8% |
| Frontier Airlines | 1,043 | 5.3%about level | 4.7% |
| Republic Airways | 1,805 | 7.8%above the others | 4.4% |
These are airport figures, not route figures: every scheduled departure from RDU and ORD, to any destination, in hours the weather report called bad. The airline rows count each carrier’s departures from RDU on every route.
Weather source and limits. In full: RDU (airlines), ORD, 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 |
|---|---|---|---|---|---|
| United Airlines | 3,757 | 80.2% | 1.01% | -8 min | 7.4% |
| Republic Airways | 2,178 | 75.3% | 3.03% | -6 min | 10.1% |
| American Airlines | 2,075 | 85.0% | 1.69% | -12 min | 7.1% |
| Envoy Air | 1,511 | 75.2% | 1.59% | -6 min | 9.7% |
| SkyWest Airlines | 292 | 82.3% | 2.40% | -8 min | 7.4% |
| Frontier Airlines | 249 | 55.4% | 6.02% | 7 min | 22.3% |
United Airlines flew 37.3% of the 10,062 flights listed. Frontier Airlines cancelled 6.02% of its flights here against 1.01% for United Airlines.
American Airlines arrived on time 29.6 percentage points more often than Frontier Airlines on this route.
Flights on this route
Flight numbers with at least 600 operations here and still on the schedule.
| Flight | Scheduled | Operations | On time |
|---|---|---|---|
| AA2849 American Airlines | 7:45 AM | 757 | 84.0% |
Weekly and seasonal patterns
By day of week
Tuesday is historically the most reliable day and Friday the least, a gap of 5.5 percentage points.
By month
- Jan: 79.2%
- Feb: 82.1%
- Mar: 78.6%
- Apr: 78.4%
- May: 79.5%
- Jun: 75.2%
- Jul: 68.7%
- Aug: 74.6%
- Sep: 83.4%
- Oct: 83.6%
- Nov: 84.9%
- Dec: 82.2%
July is historically the weakest month and November the strongest, a spread of 16.2 percentage points.
Reliability over time
July 2023 – July 2026
- July 2023: 64.7% from 227 flights
- August 2023: 73.2% from 244 flights
- September 2023: 85.3% from 240 flights
- October 2023: 93.6% from 234 flights
- November 2023: 93.0% from 244 flights
- December 2023: 92.5% from 239 flights
- January 2024: 77.9% from 227 flights
- February 2024: 88.2% from 213 flights
- March 2024: 89.8% from 244 flights
- April 2024: 80.7% from 244 flights
- May 2024: 72.4% from 275 flights
- June 2024: 77.6% from 266 flights
- July 2024: 74.6% from 281 flights
- August 2024: 74.8% from 292 flights
- September 2024: 82.5% from 293 flights
- October 2024: 89.2% from 307 flights
- November 2024: 88.5% from 270 flights
- December 2024: 84.1% from 264 flights
- January 2025: 83.6% from 232 flights
- February 2025: 79.9% from 214 flights
- March 2025: 79.1% from 257 flights
- April 2025: 86.5% from 258 flights
- May 2025: 84.1% from 297 flights
- June 2025: 71.9% from 272 flights
- July 2025: 65.2% from 276 flights
- August 2025: 75.6% from 273 flights
- September 2025: 82.7% from 266 flights
- October 2025: 71.2% from 327 flights
- November 2025: 75.1% from 309 flights
- December 2025: 71.8% from 290 flights
- January 2026: 76.1% from 233 flights
- February 2026: 78.8% from 244 flights
- March 2026: 69.1% from 316 flights
- April 2026: 70.7% from 354 flights
- May 2026: 81.0% from 374 flights
- June 2026: 76.1% from 327 flights
- July 2026: 69.2% from 341 flights
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 74.6% against 80.8% in the 12 months before — declining by 6.2 percentage points.
Data and methodology
Calculated by FlyerIntel from 10,064 RDU → ORD 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