84% of flights from Knoxville to Denver arrived on time over the past 12 months. That is better than the typical U.S. route. The 8 a.m. departures ran on time 93% of the time; the 4 p.m. ones 79%. Most reliable airline: United Airlines (88%). 8% of flights arrived more than an hour late or not at all.
How late?
The on-time rate treats a flight 20 minutes late the same as one 5 hours late. Here's the split for TYS → DEN: when a flight was late, it was under 45 minutes late 43% of the time. About 1 in 15 flights landed an hour or more late, and 1 in 74 three hours or more; 0.5% were cancelled outright.
- On time or early84%
- 15–30 min late3.9%
- 30–60 min late4.2%
- 1–2 hours late4.1%
- 2–3 hours late1.4%
- 3+ hours late1.4%
- Diverted0.7%
- Cancelled0.5%
Share of all 1,029 scheduled flights, past 12 months, by arrival time against schedule.
By airline
| Airline | Flights | On time | Cancelled | Typical arrival | 1h+ late | Avg when late | Operated by |
|---|---|---|---|---|---|---|---|
| United Airlines | 728 | 88% | 0.7% | −13 min | 5.9% | +107 min | United Airlines 54%, SkyWest 46% |
| Frontier Airlines | 131 | 76% | 0.0% | −16 min | 9.2% | +60 min | Frontier Airlines |
| Southwest Airlines | 104 | 64% | 0.0% | −6 min | 13.5% | +74 min | Southwest Airlines |
| Allegiant Air | 66 | — | — | — | — | — | Allegiant Air |
Airline = the name on the ticket. Regional flights (e.g. "Delta Connection") count under the ticketing airline, and the operator is listed.
Best time of day to fly
On-time rate by scheduled departure hour (local time at TYS). Delays build through the day as late planes knock on, so early flights usually do best.
By airline and hour
| Departs | United Airlines |
|---|---|
| 8 a.m. | 93% |
| 4 p.m. | 82% |
Last flight of the day
On TYS → DEN, each airline's last flight of the day was cancelled 0.5% of the time, against 0.8% for its earlier flights, so here the last flight is actually the safer one. It arrived 3+ hours late 2.5% of the time (earlier flights: 0.5%). It matters more than the numbers suggest. Miss an earlier flight and there's another one that evening; miss the last one and you're usually waiting until morning.
| Airline | Last departure | Last: cancelled | Last: 3h+ late | Earlier: cancelled | Next morning |
|---|---|---|---|---|---|
| United Airlines | 4:56 p.m. | 0.5% | 2.5% | 0.8% | first flight 8:48 a.m. |
Last flight = the airline's last scheduled departure on this route that day, on days it flies the route at least twice; past 12 months. Times are typical scheduled times over the latest three months.
By month
Each calendar month pooled over 2023–2026. Best: March (92%). Worst: June (71%).
By day of week
| Day | Flights | On time | Cancelled |
|---|---|---|---|
| Monday | 160 | 81% | 0.0% |
| Tuesday | 120 | 87% | 0.0% |
| Wednesday | 128 | 87% | 0.0% |
| Thursday | 167 | 79% | 0.0% |
| Friday | 150 | 83% | 0.0% |
| Saturday | 126 | 84% | 2.4% |
| Sunday | 178 | 89% | 1.1% |
Why flights were late
Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.
Cancellations: weather 4 · air traffic/airport 1
Month by month
Flight numbers on this route
Regular flights with at least 120 scheduled trips in the past year. Sorted by departure time.
| Flight | Departs | Flights | On time | Cancelled | Typical arrival | Operated by |
|---|---|---|---|---|---|---|
| UA 1256 | 8:48 a.m. | 123 | 94% | 0.0% | −18 min | United Airlines |
| F9 4369 | 8:19 p.m. | 129 | 77% | 0.0% | −16 min | Frontier Airlines |
Worst days in the past year
| Date | Flights | On time | Cancelled |
|---|---|---|---|
| Oct 27, 2025 | 3 | 0% | 0 |
| Jul 10, 2026 | 4 | 25% | 0 |
| Aug 12, 2026 | 4 | 25% | 0 |
| Jul 29, 2026 | 4 | 25% | 0 |
| Jul 22, 2026 | 4 | 25% | 0 |
Questions
How often are flights from TYS to DEN on time?
84% of 1,029 scheduled flights from Knoxville, TN to Denver, CO arrived within 15 minutes of schedule between September 2025 and August 2026. 0.5% were cancelled.
What is the best time of day to fly TYS to DEN?
Flights scheduled to leave at 8 a.m. were the most reliable (93% on time). The 4 p.m. departures were the least (79%).
Which airline is most on time from TYS to DEN?
United Airlines: 88% of its 728 flights on the route arrived on time. Frontier Airlines: 76%. Southwest Airlines: 64%.
What month has the most delays from TYS to DEN?
June (71% on time). The best month is March (92%), over 2023–2026.
Is the last flight of the day from TYS to DEN more likely to be cancelled?
No, the opposite. Each airline's last TYS–DEN flight of the day was cancelled 0.5% of the time over the past year, against 0.8% for its earlier flights. If the last flight is cancelled, the next one is usually the following morning.
Related
- DEN → TYS (return)
- McGhee Tyson (TYS) delays by hour
- Flights into Denver (DEN)
- United Airlines on-time record
- Frontier Airlines on-time record
- Southwest Airlines on-time record
- Allegiant Air on-time record
- Connecting off this flight? Check the risk
Domestic flights by the airlines that report to the U.S. DOT, plus their regional partners. "On time" means arriving less than 15 minutes after schedule; cancelled and diverted flights count as not on time. Past performance is a guide, not a forecast. Method.