Carrier route record
UADEN→PIT
United Airlines · Denver to Pittsburgh
- Flights
- 819
- Period
- September 2025 to August 2026
- Share of route
- 50%
- Carriers
- 3
Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with United Airlines.
United on DEN to PIT lands a B+, 4 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 about an hour on average. That rests on 819 flights, with a median arrival 6 minutes early.
The US average over the same twelve months is 77.3%, so there is little to separate United on DEN to PIT from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
81.2%
Arrivals under 15 minutes late, of 814 completed flights
Avg delay
58 min
Across delayed arrivals only, not all flights
Cancelled
0.49%
National rate is 1.89%
Whole route
74.1%
Every carrier on DEN to PIT, 1,622 flights
These figures cover 819 flights between September 2025 and August 2026. The median arrival is 6 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.
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Carrier by carrier
United against every carrier on DEN to PIT
United flew 819 of the 1,622 flights on DEN to PIT, most of the route. Its 81.2% on time is 7 points better than the route as a whole, which runs 74.1%. Ranked by on-time rate it is number two of three carriers on the route, where the range runs from Frontier at 100.0% to Southwest at 65.4%. One 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 | 35 | 100.0% | — | 0.00% | A+ |
| United Airlines (this page) | 819 | 81.2% | 58 min | 0.49% | B+ |
| Southwest Airlines | 768 | 65.4% | 57 min | 0.52% | C+ |
Flight by flight
United flight numbers on DEN to PIT
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 11 points, against half a point between the best and worst carrier.
- 5am–8am—
- 8am–11am365 flights84.1%
- 11am–2pm—
- 2pm–5pm91 flights87.9%
- 5pm–8pm363 flights76.6%
- 8pm–5am—
Scale runs 70% to 95%. Rows with fewer than 30 flights show a dash.
The best window here is not the first bank but the 2pm–5pm slot at 87.9% on time, ahead of 5pm–8pm at 76.6%. Where the curve peaks mid-day rather than at dawn, the constraint is usually congestion at one end rather than the aircraft's own rotation. The 8am–11am window is the busiest, with 365 flights scheduled in it.
Across the year
United on DEN to PIT through the year
August is the worst month at 63.9% on time, 29 points below February, the best at 92.9%. 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 93 flights.
Across the week, Friday is the strongest day at 84.2% on time and Thursday the weakest at 76.5%, a spread of 8 points.
Arrival by arrival
How late United on DEN to PIT runs when it is late
The 153 late arrivals split 53 under half an hour, 59 between 30 and 60 minutes, and 41 an hour or more.
- 15+ min early192 flights23.6%
- Within 15 min469 flights57.6%
- 15–29 min late53 flights6.5%
- 30–59 min late59 flights7.2%
- 1–2 hours late24 flights2.9%
- 2+ hours late17 flights2.1%
Scale runs 0% to 100%.
Share of 814 completed flights by arrival against schedule.
37 of 153 late departures made up the time and arrived on time, 24% of them. 37 flights left on time and still arrived late.
The worst days
Worst days for United on DEN to PIT
The latest arrival of the period was on 14 August 2026, 7 hours 1 minute behind schedule; most of its delay minutes were filed as a late-arriving aircraft. The same cause led on five of the five worst days.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 14 August 2026 | 7 hours 1 minute | Late-arriving aircraft |
| 8 June 2026 | 4 hours 56 minutes | Late-arriving aircraft |
| 24 June 2026 | 4 hours 46 minutes | Late-arriving aircraft |
| 22 May 2026 | 4 hours 14 minutes | Late-arriving aircraft |
| 15 August 2026 | 3 hours 39 minutes | Late-arriving aircraft |
Delay causes
Why United runs late on this route
Late-arriving aircraft accounts for 56% of the 8,917 delay minutes carriers reported here, and the remaining four split what is left.
- 56%Late-arriving aircraft
- 25%Carrier
- 17%National Airspace System
- 2%Extreme weather
56% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 8,917 reported delay minutes here, that single category outweighs weather by 33 to one. The split is drawn from 8,917 reported delay minutes.
Cancellations are rare at 0.49%, 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
5.0% 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 about an hour, which a normal layover absorbs.
The 1,290 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.
The return leg is a different operation and performs like one: it runs 86.4% on time across 820 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. 819 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 DEN to PIT
Put together: treat all of this as provisional. 819 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 81.2% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 814 completed flights over 12 months sit behind that.
Related
Where to go next
- DEN to PIT, every carrier
- United on PIT to DEN, the return leg
- Southwest Airlines on DEN to PIT65.4%
- United Airlines network-wide record
- Denver International (DEN) delay statistics
- Pittsburgh International (PIT) 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.