Best Time to Fly SDF to DEN: On-Time Stats by Hour & Airline
Louisville Muhammad Ali International → Denver International
Data through July 2026 · Last updated October 18, 2026
Over the last 12 months, 83.5% of Louisville (SDF) to Denver (DEN) flights arrived on time (1,097 scheduled flights). That is 5.9 points above the national average of 77.6%.
United Airlines was the most punctual of the 2 airlines on the route at 85.0%, while Southwest Airlines trailed at 80.7%.
September has been the best month (90% on time) and Sunday the weakest day of the week (79%).
1.0% of flights were cancelled, versus 1.8% nationally.
SDF to DEN 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 | 85.0% | 69 min | 1.0% | 730 |
| Southwest Airlines | 80.7% | 52 min | 1.1% | 367 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly SDF to DEN
On-time arrival % by scheduled departure hour (local time), 2,141 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 5am–6am | 97.3% | 0.0% | 37 |
| 6am–7am | 93.9% | 1.8% | 166 |
| 7am–8am | 92.2% | 0.0% | 64 |
| 8am–9am | 89.2% | 1.2% | 413 |
| 9am–10am | 89.4% | 0.6% | 331 |
| 10am–11am | Limited data | 20 | |
| 11am–12pm | 79.4% | 0.0% | 63 |
| 12pm–1pm | Limited data | 10 | |
| 1pm–2pm | 79.3% | 0.8% | 118 |
| 2pm–3pm | Limited data | 13 | |
| 3pm–4pm | 79.2% | 1.0% | 729 |
| 4pm–5pm | 57.1% | 1.6% | 64 |
| 5pm–6pm | 71.9% | 0.0% | 32 |
| 6pm–7pm | 64.9% | 0.0% | 37 |
| 7pm–8pm | Limited data | 8 | |
| 8pm–9pm | 44.4% | 0.0% | 36 |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on SDF to DEN
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) | 85.0% | +1.6 pts | 0.0% | 40 |
| Christmas & New Year (Dec 20 - Jan 3) | 83.3% | -0.1 pts | 0.0% | 90 |
| Summer peak (Jun 15 - Aug 15) | 80.7% | -2.7 pts | 0.8% | 379 |
| All other days | 83.4% | — | 1.0% | 1,632 |
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).