Carrier route record
UATYS→DEN
United Airlines · Knoxville to Denver
- Flights
- 335
- Period
- July 2025 to June 2026
- Share of route
- 35%
- Carriers
- 5
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.
United on TYS to DEN lands a B+, 4 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 a little over an hour on average. That is a workable record, not a spotless one. That rests on 335 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 TYS to DEN from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
81.4%
Arrivals under 15 minutes late, of 334 completed flights
Avg delay
73 min
Across delayed arrivals only, not all flights
Cancelled
0.00%
National rate is 1.81%
Whole route
84.8%
Every carrier on TYS to DEN, 967 flights
These figures cover 335 flights between July 2025 and June 2026. Beyond the headline rate, 8.1% 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 TYS to DEN
United flew 335 of the 967 flights on TYS to DEN, about 35% of it. Its 81.4% on time is 3 points worse than the route as a whole, which runs 84.8%. Ranked by on-time rate it is number three of five carriers on the route, where the range runs from SkyWest at 93.0% to Southwest at 69.0%. Three 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 |
|---|---|---|---|---|---|
| SkyWest Airlines | 394 | 93.0% | 102 min | 1.27% | A |
| Allegiant Airthin sample | 66 | 82.5% | 52 min | 0.00% | B+ |
| United Airlines (this page)thin sample | 335 | 81.4% | 73 min | 0.00% | B+ |
| Frontier Airlinesthin sample | 129 | 75.2% | 92 min | 0.00% | B+ |
| Southwest Airlinesthin sample | 43 | 69.0% | 86 min | 0.00% | C+ |
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 16 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–11am64 flights93.8%
- 11am–2pm—
- 2pm–5pm199 flights78.3%
- 5pm–8pm72 flights79.2%
- 8pm–5am—
Scale runs 70% to 100%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 93.8% of the time, against 78.3% for the afternoon window. That is 16 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 2pm–5pm window is the busiest, with 199 flights scheduled in it.
Across the year
United on TYS to DEN through the year
August is the worst month at 54.8% on time, 42 points below November, the best at 96.8%. 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 62 flights.
Across the week, Wednesday is the strongest day at 91.5% on time and Thursday the weakest at 71.7%. 20 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 59% of the 4,517 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.
- 59%National Airspace System
- 18%Carrier
- 17%Late-arriving aircraft
- 6%Extreme weather
59% 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 2,675 minutes out of 4,517, against a national NAS share of 21%. The split is drawn from 4,517 reported delay minutes.
Cancellations are rare at 0.00%, below the national 1.81% and low enough to earn the plus on the grade. Almost no flights are called off; the risk here is arriving late, not not arriving.
Connections and stage length
What a delay here costs
8.1% 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 a little over an hour, which a normal layover absorbs.
The 1,162 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 81.0% on time across 336 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.
One caution: this is a thin sample. 335 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 TYS to DEN
Put together: treat all of this as provisional. 335 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 81.4% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 334 completed flights over 12 months sit behind that.
Related
Where to go next
- TYS to DEN, every carrier
- United on DEN to TYS, the return leg
- SkyWest Airlines on TYS to DEN93.0%
- Frontier Airlines on TYS to DEN75.2%
- United Airlines network-wide record
- Denver International (DEN) delay statistics
- The best time of day to fly, according to 7.04 million flight records
- Connecting flights: how much buffer the data says you need
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.