76% of flights from Newark to Louisville arrived on time over the past 12 months. That is about the typical U.S. route. The 10 a.m. departures ran on time 86% of the time; the 8 p.m. ones 67%. 12% 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 EWR → SDF: when a flight was late, it was under 45 minutes late 48% of the time. About 1 in 15 flights landed an hour or more late, and 1 in 58 three hours or more; 5.7% were cancelled outright.
- On time or early76%
- 15–30 min late5.4%
- 30–60 min late6.1%
- 1–2 hours late3.4%
- 2–3 hours late1.4%
- 3+ hours late1.7%
- Diverted0.1%
- Cancelled5.7%
Share of all 1,035 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 | 1,034 | 76% | 5.7% | −13 min | 6.6% | +84 min | Republic Airways 98%, GoJet 1%, United Airlines 0% |
| Spirit Airlines | 1 | — | — | — | — | — | Spirit Airlines |
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 EWR). Delays build through the day as late planes knock on, so early flights usually do best.
By airline and hour
| Departs | United Airlines |
|---|---|
| 10 a.m. | 86% |
| 5 p.m. | 74% |
| 6 p.m. | 73% |
| 8 p.m. | 67% |
Last flight of the day
On EWR → SDF, each airline's last flight of the day was cancelled 8.4% of the time, against 4.2% for its earlier flights (2.0× as often). It arrived 3+ hours late 2.2% of the time (earlier flights: 1.6%). 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 | 8:29 p.m. | 8.4% | 2.2% | 4.2% | first flight 10:05 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.
If you need to be in SDF tonight, book an earlier flight so there's a backup if it's cancelled.
By month
Each calendar month pooled over 2023–2026. Best: September (87%). Worst: July (65%).
By day of week
| Day | Flights | On time | Cancelled |
|---|---|---|---|
| Monday | 152 | 75% | 8.6% |
| Tuesday | 150 | 77% | 6.0% |
| Wednesday | 148 | 80% | 2.0% |
| Thursday | 149 | 77% | 6.7% |
| Friday | 150 | 79% | 2.7% |
| Saturday | 135 | 79% | 3.7% |
| Sunday | 151 | 66% | 9.9% |
Why flights were late
Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.
Cancellations: weather 37 · air traffic/airport 22
Month by month
Not enough months with data to draw a trend.
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 3415 | 6:00 p.m. | 134 | 75% | 7.5% | −13 min | Republic Airways |
| UA 3609 | 8:45 p.m. | 228 | 72% | 8.3% | −13 min | Republic Airways |
Worst days in the past year
| Date | Flights | On time | Cancelled |
|---|---|---|---|
| Nov 4, 2025 | 3 | 0% | 1 |
| Aug 7, 2026 | 3 | 0% | 2 |
| Nov 9, 2025 | 3 | 0% | 2 |
| Jun 12, 2026 | 3 | 0% | 1 |
| Feb 24, 2026 | 3 | 0% | 3 |
Nearby airport alternatives
Other ways to make the same trip, using airports within 60 miles of Newark or Louisville. None has been clearly more reliable than EWR → SDF.
| Route | Flights | On time | Cancelled |
|---|---|---|---|
| EWR → SDF (this route) | 1,035 | 76% | 5.7% |
| LGA → SDF LaGuardia to Louisville Muhammad Ali | 1,201 | 76% | 4.1% |
Questions
How often are flights from EWR to SDF on time?
76% of 1,035 scheduled flights from Newark, NJ to Louisville, KY arrived within 15 minutes of schedule between September 2025 and August 2026. 5.7% were cancelled.
What is the best time of day to fly EWR to SDF?
Flights scheduled to leave at 10 a.m. were the most reliable (86% on time). The 8 p.m. departures were the least (67%).
What month has the most delays from EWR to SDF?
July (65% on time). The best month is September (87%), over 2023–2026.
Is the last flight of the day from EWR to SDF more likely to be cancelled?
Yes. Each airline's last EWR–SDF flight of the day was cancelled 8.4% of the time over the past year, against 4.2% for its earlier flights. If the last flight is cancelled, the next one is usually the following morning.
Related
- SDF → EWR (return)
- Newark (EWR) delays by hour
- Flights into Louisville Muhammad Ali (SDF)
- United Airlines on-time record
- Spirit Airlines 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.