| Date | From | To | Departure | Arrival | Status | |
|---|---|---|---|---|---|---|
| Mar 28 | DEN | SDF | 17:30 | 21:34 |
Landed
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Track > |
| Mar 27 | DEN | SDF | 17:41 | 21:39 |
Landed
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| Mar 26 | DEN | SDF | 18:14 | 22:14 |
Landed Late
|
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| Mar 25 | DEN | SDF | 17:31 | 21:38 |
Landed
|
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| Mar 24 | DEN | SDF | 17:38 | 21:46 |
Landed
|
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| Mar 23 | DEN | SDF | 17:34 | 21:37 |
Landed
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| Mar 22 | DEN | SDF | 17:43 | 21:50 |
Landed
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| Mar 21 | DEN | SDF | 17:41 | 21:48 |
Landed
|
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| Mar 20 | DEN | SDF | 17:42 | 21:49 |
Landed
|
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| Mar 19 | DEN | SDF | 17:37 | 21:45 |
Landed
|
Track > |
United Airlines Flight UA421 connects Denver, United States to Louisville, United States, taking off from Denver International Airport DEN and landing at Louisville International Airport SDF.
How long is the UA421 flight from Denver to Louisville?
The average flight time from Denver to Louisville is 2 hours and 4 minutes. The flight distance is 1644 km / 1021 miles and the average flight speed is 790 km/h / 491 mph.
What is the On-Time Performance (OTP) of United Airlines Flight UA421 Denver to Louisville?
The Airportia On-Time Performance Rating for United Airlines Flight UA421 is 5/5 stars. This metric is calculated using data from the past 10 flights.
Which terminal is the flight UA421 arriving at?
Flight UA421 arrives at Louisville International Airport (SDF) Terminal 2.
When was the latest UA421 flight?
The latest flight took off on Sunday, March 29th, 2026 with the flight status being Landed on 21:34.
How else can the flight UA421 be referenced as?
This United Airlines flight can also be referenced as UAL421, UA0421, UA 421, UAL 421.
How often is flight UA421 delayed?
On average, 10% of all UA421 flights are delayed. The average delay is 15 minutes.
Can I get compensation for my delayed or cancelled UA421 flight or baggage issues?
If your UA421 flight was cancelled, delayed, or if you experienced baggage issues such as delayed, damaged, or lost bags, you may be entitled to compensation. Compensation amounts and eligibility depend on various regulations, including EC 261/2004, UK261, CA Montreal Convention, US GoodWill, BR-ANAC, SA-GACA and TK-SHY.
See our UA421 Flight Tracker above for more details.
Flight UA421 is code-shared by 1 airline using the flight number AC4715
Other flights departing from Denver DEN: UA323, UA1246, WN4133, UA4638
Other flights arriving at Louisville SDF: UA4018, AA3119, AA1427, WN1678
All flights connecting Denver DEN to Louisville SDF.