United Flight NK3531 Deals & Information (2025/2026)

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United Flight 3531 Route Deals From $101

The cheapest prices found with in the last 7 days for return flights were $149 and $101 for one-way flights to Louisville Intl. for the period specified. Prices and availability are subject to change. Additional terms apply.

Thu, Oct 30 - Fri, Oct 31
EWR
Newark Liberty Intl. Airport
SDF
Louisville Intl.
$149 Roundtrip, found 4 days ago
$149
Roundtrip
found 4 days ago
Select United flight, departing Thu, Oct 30 from Newark Liberty Intl. Airport to Louisville Intl., returning Fri, Oct 31, priced at $149 found 4 days ago
Wed, Aug 20 - Wed, Aug 27
EWR
Newark Liberty Intl. Airport
SDF
Louisville Intl.
$197 Roundtrip, found 14 hours ago
$197
Roundtrip
found 14 hours ago
Select United flight, departing Wed, Aug 20 from Newark Liberty Intl. Airport to Louisville Intl., returning Wed, Aug 27, priced at $197 found 14 hours ago

Frequently asked questions

What route does flight number UA3531 take?
UA3531 is used on multiple routes, but the most common is between ORD and Louisville, KY Airport (SDF-Louisville Intl.). If on a direct flight, you'll stroll through arrivals in approximately 1 hour and 24 minutes. Multi-stop flights can also travel under this number, as can flights on other routes.
What terminal does UA3531 fly out of?
If you're heading off from Chicago, IL Airport (ORD-O'Hare Intl.), there's an excellent chance you'll board from Terminal 2. The most frequented route for flight number UA3531 is O'Hare Airport to Louisville Muhammad Ali Intl. Airport, which is a nonstop flight.
What kind of plane is on flight number UA3531?
If you've booked a ticket on flight UA3531 from O'Hare Intl. Airport (ORD) to Louisville, KY Airport (SDF-Louisville Intl.), you're likely to be heading off on the Embraer 170. This flight number serves numerous routes, but this is the most common one.
If I am not able to travel due to COVID-19, can I change my flight to a later date?
For more info about changing your UA3531 flight with Travelocity, please visit our Customer Service Portal.