Carrier route record
UACMH→IAD
United Airlines · Columbus to Washington
- Flights
- 408
- Period
- September 2025 to August 2026
- Share of route
- 44%
- Carriers
- 2
Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with United Airlines.
United on CMH to IAD lands a B+, 2 points better than the national rate of 77.3%. About one flight in five arrives 15 minutes late or worse, and those flights are late by an hour and a half on average. That rests on 408 flights, with a median arrival 4 minutes early.
The US average over the same twelve months is 77.3%, so there is little to separate United on CMH to IAD from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
78.8%
Arrivals under 15 minutes late, of 405 completed flights
Avg delay
91 min
Across delayed arrivals only, not all flights
Cancelled
0.74%
National rate is 1.89%
Whole route
84.9%
Every carrier on CMH to IAD, 935 flights
These figures cover 408 flights between September 2025 and August 2026. Beyond the headline rate, 8.4% of arrivals land a full hour or more behind schedule, against 8.3% nationally.
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Carrier by carrier
United against every carrier on CMH to IAD
United flew 408 of the 935 flights on CMH to IAD, about 44% of it. Its 78.8% on time is 6 points worse than the route as a whole, which runs 84.9%. Ranked by on-time rate it is last of two carriers on the route, where the range runs from Republic at 89.7% to United at 78.8%.
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Republic Airways | 527 | 89.7% | 61 min | 0.95% | A+ |
| United Airlines (this page) | 408 | 78.8% | 91 min | 0.74% | B+ |
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
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 17 points, against half a point between the best and worst carrier.
- 5am–8am—
- 8am–11am144 flights87.3%
- 11am–2pm—
- 2pm–5pm105 flights70.5%
- 5pm–8pm46 flights76.1%
- 8pm–5am113 flights76.8%
Scale runs 60% to 95%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 87.3% of the time, against 70.5% for the afternoon window. That is 17 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8am–11am window is the busiest, with 144 flights scheduled in it.
Across the year
United on CMH to IAD through the year
- Jul–Sep 202569 flights87.0%
- Oct–Dec 202575 flights73.3%
- Jan–Mar 2026130 flights78.1%
- Apr–Jun 202692 flights84.6%
- Jul–Sep 202642 flights64.3%
Scale runs 55% to 90%.
Monthly volumes are too low here to break the year into twelve reliable readings. What the twelve-month total says is 78.8% on time across 408 flights.
United on CMH to IAD did not run the same all year. Its best quarter was Jul–Sep 2025 at 87.0% on time and its weakest Jul–Sep 2026 at 64.3%, a swing of 23 points on roughly 82 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.
Across the week, Wednesday is the strongest day at 87.9% on time and Monday the weakest at 65.6%, a spread of 22 points.
Arrival by arrival
How late United on CMH to IAD runs when it is late
The 86 late arrivals split 33 under half an hour, 19 between 30 and 60 minutes, and 34 an hour or more.
- 15+ min early76 flights18.8%
- Within 15 min243 flights60.0%
- 15–29 min late33 flights8.1%
- 30–59 min late19 flights4.7%
- 1–2 hours late14 flights3.5%
- 2+ hours late20 flights4.9%
Scale runs 0% to 100%.
Share of 405 completed flights by arrival against schedule.
Time lost at the gate mostly stays lost. Of 75 departures that left 15 minutes late or more, only 4 made it up before arrival. 15 flights left on time and still arrived late.
The worst days
Worst days for United on CMH to IAD
The latest arrival of the period was on 13 March 2026, 23 hours 9 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). Three of the five worst days fell in March 2026.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 13 March 2026 | 23 hours 9 minutes | Carrier |
| 16 March 2026 | 10 hours 42 minutes | Carrier |
| 20 May 2026 | 6 hours 54 minutes | Late-arriving aircraft |
| 13 March 2026 | 5 hours 17 minutes | Late-arriving aircraft |
| 1 February 2026 | 3 hours 29 minutes | Late-arriving aircraft |
Delay causes
Why United runs late on this route
Late-arriving aircraft accounts for 46% of the 7,817 delay minutes carriers reported here, and the remaining four split what is left.
- 46%Late-arriving aircraft
- 36%Carrier
- 14%National Airspace System
- 4%Extreme weather
46% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 7,817 reported delay minutes here, that single category outweighs weather by 12 to one. The split is drawn from 7,817 reported delay minutes.
The largest share of delay minutes, 36%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 2,792 of the 7,817 delay minutes reported here.
Cancellations are rare at 0.74%, below the national 1.89% 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.
Connections and stage length
What a delay here costs
8.4% of arrivals land an hour or more late, close to the national 8.3%, so 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.
At 299 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 8am–11am window matters as much as it does.
The return leg is a different operation and performs like one: it runs 83.0% on time across 409 flights, 4 points above this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 4 points of difference.
One caution: this is a thin sample. 408 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.
What to do with this
Booking United on CMH to IAD
Put together: treat all of this as provisional. 408 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 78.8% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 405 completed flights over 12 months sit behind that.
Related
Where to go next
- CMH to IAD, every carrier
- United on IAD to CMH, the return leg
- Republic Airways on CMH to IAD89.7%
- United Airlines network-wide record
- John Glenn Columbus International (CMH) delay statistics
- Washington Dulles International (IAD) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.05 million flight records
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.