Carrier route record
UARDU→ORD
United Airlines · Raleigh to Chicago
- Flights
- 1,295
- Period
- July 2025 to June 2026
- Share of route
- 36%
- Carriers
- 7
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.
United on RDU to ORD lands a B, about a point worse than the national rate of 77.6%. About one flight in four arrives 15 minutes late or worse, and those flights are late by an hour and a half on average. That is a workable record, not a spotless one. That rests on 1,295 flights. The strongest carrier on the route with a full sample, American Airlines, flew 553 at 82.2% on time.
American Airlines is the most reliable of the three carriers covered here at 82.2% on time across 553 flights.
Key figures
On time
76.3%
Arrivals under 15 minutes late, of 1,277 completed flights
Avg delay
87 min
Across delayed arrivals only, not all flights
Cancelled
1.16%
National rate is 1.81%
Whole route
74.4%
Every carrier on RDU to ORD, 3,589 flights
These figures cover 1,295 flights between July 2025 and June 2026. Beyond the headline rate, 8.5% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Carrier by carrier
United against every carrier on RDU to ORD
United flew 1,295 of the 3,589 flights on RDU to ORD, about 36% of it. Its 76.3% on time is 2 points better than the route as a whole, which runs 74.4%. Ranked by on-time rate it is number three of seven carriers on the route, where the range runs from American at 82.2% to PSA at 50.0%. Three of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The choice of carrier is not cosmetic here. American Airlines arrives on time 82.2% of the time; Republic Airways manages 70.7%. Sample sizes sit next to every figure, because a two-point gap across 1,018 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| American Airlines | 553 | 82.2% | 145 min | 3.44% | B− |
| SkyWest Airlinesthin sample | 67 | 77.3% | 138 min | 0.00% | B+ |
| United Airlines (this page) | 1,295 | 76.3% | 87 min | 1.16% | B |
| Envoy Air | 523 | 72.3% | 86 min | 1.72% | C |
| Republic Airways | 1,018 | 70.7% | 75 min | 3.63% | C− |
| Frontier Airlinesthin sample | 131 | 57.7% | 139 min | 5.34% | D− |
| PSA Airlinesthin sample | 2 | 50.0% | 31 min | 0.00% | F+ |
Republic Airways cancels 3.6% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.
Flight by flight
United flight numbers on RDU to ORD
Departure window
When United runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 43 points, against 12 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am262 flights89.2%
- 8am–11am399 flights88.4%
- 11am–2pm313 flights78.6%
- 2pm–5pm36 flights62.9%
- 5pm–8pm283 flights46.6%
- 8pm–5am2 flights—
Scale runs 40% to 95%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 46.6% on time, against 89.2% for the 5am–8am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 8am–11am window is the busiest, with 399 flights scheduled in it.
Across the year
United on RDU to ORD through the year
July is the worst month at 68.1% on time, 13 points below February, the best at 81.1%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. October was the busiest month here, with 119 flights.
Across the week, Tuesday is the strongest day at 81.5% on time and Friday the weakest at 69.4%. 12 points is a smaller lever than departure hour, but it is free.
Delay causes
Why United runs late on this route
One category carries most of the weight here. National Airspace System accounts for 43% of the 26,000 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.
- 43%National Airspace System
- 27%Late-arriving aircraft
- 19%Carrier
- 11%Extreme weather
Extreme weather accounts for 11% of delay minutes, well above the single-digit share typical across the system. Weather delays are lumpy: they arrive as whole bad days rather than as a steady drag, so the monthly strip above is the more useful view of the risk. The national share is 6%, so this operation carries roughly 1.8 times the usual weather exposure. The split is drawn from 26,369 reported delay minutes.
43% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 11,000 minutes out of 26,000, against a national NAS share of 21%.
Cancellations sit at 1.16% against a national 1.81%, which is ordinary. Diversions add another 0.23%.
Connections and stage length
What a delay here costs
8.5% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last an hour and a half, which a normal layover absorbs.
The 646 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
The return leg runs 76.8% on time across 1,298 flights, within half a point of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
The sample behind these figures is 1,295 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.
What to do with this
Booking United on RDU to ORD
Put together: the calendar is the biggest lever here, not the carrier or the hour. February runs 81.1% on time and July 68.1%, a swing of 13 points. If the dates move at all, move them out of July before you think about anything else. 1,277 completed flights over 12 months sit behind that.
Related
Where to go next
- RDU to ORD, every carrier
- United on ORD to RDU, the return leg
- American Airlines on RDU to ORD82.2%
- Envoy Air on RDU to ORD72.3%
- Republic Airways on RDU to ORD70.7%
- Frontier Airlines on RDU to ORD57.7%
- United Airlines network-wide record
- Raleigh-Durham International (RDU) delay statistics
- Chicago O'Hare International (ORD) delay statistics
- Same route, different airline: where the carrier you pick matters most
- The best time of day to fly, according to 7.04 million flight records
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.