Route reliability record
TYS→DEN
Knoxville to Denver
- Flights
- 967
- Period
- July 2025 to June 2026
- Distance
- 1,162 mi
- Carriers
- 5
This route earns a B+. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 7 points better than the national rate of 77.6%. When something does go wrong the average delay runs an hour and a half. That rests on 967 TYS to DEN flights, with a median arrival 12 minutes early.
Best time to fly TYS to DEN: a 8am–11am departure, ideally on a Wednesday. Flights in that window arrived on time 93.4% of the time and Wednesday flights 91.1%, against 84.8% for the route overall.
Set against the rest of the country, this route's record is 7 points better than the US average of 77.6%. That gap is worth roughly 72 fewer late arrivals for every thousand flights.
Key figures
On time
84.8%
Arrivals under 15 minutes late, of 956 completed flights
Avg delay
82 min
Across delayed arrivals only, not all flights
Cancelled
0.52%
National rate is 1.81%
Best carrier
SkyWest
93.0% on time across 394 flights
These figures cover 967 flights between July 2025 and June 2026. The median arrival is 12 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.
Carrier by carrier
Which airline is most reliable on TYS to DEN
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 Airlinesthin 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+ |
Flight by flight
Flights on TYS to DEN
The flight numbers below flew this route at least 250 times in the period, busiest first. Each has its own record, with its schedule and delay causes.
Departure window
The best time of day to leave
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 23 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–8am45 flights91.1%
- 8am–11am369 flights93.4%
- 11am–2pm9 flights—
- 2pm–5pm373 flights80.3%
- 5pm–8pm117 flights70.9%
- 8pm–5am54 flights79.6%
Scale runs 60% to 100%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 93.4% of the time, against 70.9% for the evening window. That is 23 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 373 flights scheduled in it.
Across the year
When delays peak on this route
This route's year swings by 25 points from best month to worst, which is wide. An annual average tells you very little about the week you are actually flying, so read the strip rather than the headline if your dates are fixed.
August is the worst month at 69.1% on time, 25 points below January, the best at 94.2%. 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. June was the busiest month here, with 107 flights.
Across the week, Wednesday is the strongest day at 91.1% on time and Thursday the weakest at 76.8%. 14 points is a smaller lever than departure hour, but it is free.
Delay causes
Why this route gets delayed
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 12,000 reported delay minutes.
- 35%National Airspace System
- 34%Carrier
- 24%Late-arriving aircraft
- 7%Extreme weather
- 0%Security
35% 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 4,110 minutes out of 12,000, against a national NAS share of 21%. The split is drawn from 11,899 reported delay minutes.
Cancellations are rare at 0.52%, 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 actually costs
6.7% 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 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 is a different operation and performs like one: it runs 78.0% on time across 967 flights, 7 points below 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 7 points of difference.
One caution: this is a thin sample. 967 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.
Work out the risk of missing a connection in DEN after this flight
What to do with this
Booking this route
Put together: treat all of this as provisional. 967 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 84.8% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 956 completed flights over 12 months sit behind that.
Common questions
TYS to DEN questions
How often is TYS to DEN delayed?
About one flight in seven arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 15.2% of the 967 flights in this analysis, against 22.4% nationally. Delayed flights are late by an hour and a half on average.
How reliable is TYS to DEN compared with the rest of the country?
84.8% of flights arrive on time here against a national 77.6%, a difference of 7 points in its favour. That is worth a B+ on this site's grading scale.
What time of day has the fewest delays on TYS to DEN?
The 8am–11am departure window is the strongest at 93.4% on time. The 5pm–8pm window is the weakest at 70.9%, 23 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.
How bad are August delays on TYS to DEN?
August is the weakest month at 69.1% on time, compared with 94.2% in January. Across the year that is 25 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
- DEN to TYS — the return legseparate record
- Denver International (DEN) delay statistics
- SkyWest Airlines on TYS to DEN93.0%
- United Airlines on TYS to DEN81.4%
- Frontier Airlines on TYS to DEN75.2%
- TYS to ORD, a related route68.2%
- PHX to DEN, a related route77.2%
- TYS to ATL, a related route87.6%
- SkyWest Airlines on-time record93.0%
- Allegiant Air on-time record82.5%
- United Airlines on-time record81.4%
- The best time of day to fly, according to 7.04 million flight records
- Worst months to fly in the US, ranked by the data
Direction matters. TYS to DEN and DEN to TYS are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Embed TYS to DEN’s on-time badge on your site
Paste this into a web page. The badge shows the current on-time rate, cancellation rate and grade, and updates every month. Preview it, or build a badge for another route or airport.
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.