Best Time to Fly DEN to SDF: On-Time Stats by Hour & Airline
Denver International → Louisville Muhammad Ali International
Data through July 2026 · Last updated October 18, 2026
Over the last 12 months, 78.0% of Denver (DEN) to Louisville (SDF) flights arrived on time (1,096 scheduled flights). That is in line with the national average of 77.6%.
United Airlines was the most punctual of the 2 airlines on the route at 82.8%, while Southwest Airlines trailed at 68.5%.
October has been the best month (85% on time) and Thursday the weakest day of the week (67%).
0.7% of flights were cancelled, versus 1.8% nationally.
DEN to SDF on-time performance by airline
Last 12 months. Airlines with fewer than 30 completed flights are marked “limited data”.
| Airline | On time | Avg delay when late | Cancelled | Flights |
|---|---|---|---|---|
| United Airlines | 82.8% | 61 min | 0.6% | 730 |
| Southwest Airlines | 68.5% | 56 min | 1.1% | 366 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly DEN to SDF
On-time arrival % by scheduled departure hour (local time), 2,140 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 6am–7am | Limited data | 1 | |
| 7am–8am | Limited data | 1 | |
| 8am–9am | Limited data | 4 | |
| 9am–10am | 88.6% | 0.5% | 671 |
| 10am–11am | 73.8% | 0.0% | 42 |
| 11am–12pm | 79.0% | 0.0% | 62 |
| 12pm–1pm | 74.7% | 0.0% | 91 |
| 1pm–2pm | Limited data | 29 | |
| 2pm–3pm | 82.5% | 2.4% | 41 |
| 3pm–4pm | 60.6% | 1.5% | 67 |
| 4pm–5pm | 81.4% | 0.0% | 59 |
| 5pm–6pm | 70.3% | 0.7% | 759 |
| 6pm–7pm | 60.9% | 0.0% | 153 |
| 7pm–8pm | 45.8% | 1.0% | 97 |
| 8pm–9pm | Limited data | 12 | |
| 9pm–10pm | 48.0% | 2.0% | 51 |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on DEN to SDF
On-time arrivals during holiday periods compared with all other days, last 24 months.
| Period | On time | vs other days | Cancelled | Flights |
|---|---|---|---|---|
| Thanksgiving week (Tue before to Mon after) | 70.0% | -7.8 pts | 0.0% | 40 |
| Christmas & New Year (Dec 20 - Jan 3) | 74.4% | -3.3 pts | 0.0% | 90 |
| Summer peak (Jun 15 - Aug 15) | 62.1% | -15.7 pts | 0.5% | 379 |
| All other days | 77.8% | — | 0.7% | 1,631 |
Monthly on-time trend
On-time arrival % each month, with the 12-month US average for reference.
What causes delays on this route
Share of reported delay minutes, last 12 months (BTS cause categories).