Carrier route record
UAIAD→DFW
United Airlines · Washington to Dallas-Fort Worth
- Flights
- 914
- Period
- July 2025 to June 2026
- Share of route
- 47%
- Carriers
- 4
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.
United on IAD to DFW lands a B+, 2 points better than the national rate of 77.6%. 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 is a workable record, not a spotless one. That rests on 914 flights, with a median arrival 8 minutes early.
The US average over the same twelve months is 77.6%, so there is little to separate United on IAD to DFW from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
79.8%
Arrivals under 15 minutes late, of 898 completed flights
Avg delay
82 min
Across delayed arrivals only, not all flights
Cancelled
0.77%
National rate is 1.81%
Whole route
77.1%
Every carrier on IAD to DFW, 1,928 flights
These figures cover 914 flights between July 2025 and June 2026. Beyond the headline rate, 9.0% 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 IAD to DFW
United flew 914 of the 1,928 flights on IAD to DFW, about 47% of it. Its 79.8% on time is 3 points better than the route as a whole, which runs 77.1%. Ranked by on-time rate it is number two of four carriers on the route, where the range runs from Frontier at 81.3% to Republic at 66.7%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.
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 |
|---|---|---|---|---|---|
| Frontier Airlinesthin sample | 161 | 81.3% | 213 min | 3.11% | B− |
| United Airlines (this page) | 914 | 79.8% | 82 min | 0.77% | B+ |
| American Airlines | 844 | 73.3% | 108 min | 3.67% | C− |
| Republic Airwaysthin sample | 9 | 66.7% | 69 min | 0.00% | C+ |
Flight by flight
United flight numbers on IAD to DFW
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 20 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am—
- 8am–11am217 flights87.7%
- 11am–2pm345 flights86.8%
- 2pm–5pm—
- 5pm–8pm349 flights68.2%
- 8pm–5am3 flights—
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 87.7% of the time, against 68.2% for the evening window. That is 20 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5pm–8pm window is the busiest, with 349 flights scheduled in it.
Across the year
United on IAD to DFW through the year
July is the worst month at 62.8% on time, 24 points below February, the best at 87.0%. 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. May was the busiest month here, with 86 flights.
Across the week, Tuesday is the strongest day at 83.5% on time and Sunday the weakest at 75.8%. 8 points is a smaller lever than departure hour, but it is free.
Delay causes
Why United runs late on this route
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 15,000 reported delay minutes.
- 39%Late-arriving aircraft
- 28%National Airspace System
- 25%Carrier
- 7%Extreme weather
39% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 15,000 reported delay minutes here, that single category outweighs weather by 6 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 14,849 reported delay minutes.
The practical consequence: the 8am–11am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 87.7% on time here.
Cancellations are rare at 0.77%, below the national 1.81% 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
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 9.0% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.
The 1,172 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 is a different operation and performs like one: it runs 84.4% on time across 915 flights, 5 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 5 points of difference.
One caution: this is a thin sample. 914 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 IAD to DFW
Put together: treat all of this as provisional. 914 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 79.8% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 898 completed flights over 12 months sit behind that.
Related
Where to go next
- IAD to DFW, every carrier
- United on DFW to IAD, the return leg
- Frontier Airlines on IAD to DFW81.3%
- American Airlines on IAD to DFW73.3%
- United Airlines network-wide record
- Washington Dulles International (IAD) delay statistics
- Dallas/Fort Worth International (DFW) delay statistics
- Why the first flight of the morning is statistically safest
- 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.