$159 Cheap Delta flights Louisville (SDF) to Ontario (ONT)

View $159 flight on Wed, Oct 22, 2025Opens in a new window

  • Plan, book, fly with confidence

  • trending down icon

    Be in the know

    Get alerts if flight prices drop or rise*
  • bex rewards loyalty icon

    Book smarter

    Save up to 30% on select hotels after you book a flight*
  • one key icon

    Earn twice

    Earn your airline miles on top of our OneKeyCash
    Learn about One Key

$159 Cheap Delta flights Louisville (SDF) to Ontario (ONT)

Prices were available within the past 7 days and start at $159 for one-way flights and $297 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Tue, Nov 18 - Wed, Dec 3
SDF
Louisville
ONT
Ontario
$297 Roundtrip, found 1 day ago
$297
Roundtrip
found 1 day ago
Select Delta flight, departing Tue, Nov 18 from Louisville to Ontario, returning Wed, Dec 3, priced at $297 found 1 day ago
Delta
Sat, Aug 30 - Wed, Sep 24
SDF
Louisville
ONT
Ontario
$322 Roundtrip, found 1 day ago
$322
Roundtrip
found 1 day ago
Select Delta flight, departing Sat, Aug 30 from Louisville to Ontario, returning Wed, Sep 24, priced at $322 found 1 day ago
Delta
Sat, Jan 17 - Tue, Jan 20
SDF
Louisville
ONT
Ontario
$324 Roundtrip, found 3 days ago
$324
Roundtrip
found 3 days ago
Select Delta flight, departing Sat, Jan 17 from Louisville to Ontario, returning Tue, Jan 20, priced at $324 found 3 days ago
Delta
Thu, Sep 18 - Tue, Sep 23
SDF
Louisville
ONT
Ontario
$327 Roundtrip, found 1 hour ago
$327
Roundtrip
found 1 hour ago
Select Delta flight, departing Thu, Sep 18 from Louisville to Ontario, returning Tue, Sep 23, priced at $327 found 1 hour ago
Delta
Wed, Oct 22 - Sun, Oct 26
SDF
Louisville
ONT
Ontario
$367 Roundtrip, found 1 hour ago
$367
Roundtrip
found 1 hour ago
Select Delta flight, departing Wed, Oct 22 from Louisville to Ontario, returning Sun, Oct 26, priced at $367 found 1 hour ago
Flights from Louisville (SDF) to Ontario (ONT)
Origin airport
Louisville Intl.
Destination airport
Los Angeles - Ontario Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Southwest Airlines, United
Popular airline
American Airlines
Distance
1791 mi

Frequently asked questions

How much is a Delta Air Lines flight from Louisville Intl. Airport (SDF) to Los Angeles - Ontario Intl. Airport (ONT)?
Make use of the "Price (lowest to highest)" filter on Expedia to search for cheap Delta Air Lines round-trip flights from $297 from SDF to ONT. Affordable one-way fares from $159 are also available.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.
What is the cheapest month to fly from SDF to ONT with Delta Air Lines?
Browse for round-trip or one-way flights to Ontario in January or April. You could find a cheap fare with Delta Air Lines during these off-peak times.
What is the cheapest time to book flights from Louisville Intl. Airport (SDF) to Los Angeles - Ontario Intl. Airport (ONT) with Delta Air Lines?
Start searching one to three months ahead of your departure date to get cheaper fares on Delta Air Lines flights from Louisville Intl. Airport (SDF) to Los Angeles - Ontario Intl. Airport (ONT). You can save 25% by booking your domestic flight 34 to 86 days in advance versus last-minute reservations made 6 to 12 days out. You could also reduce costs by buying your fare on a Sunday, as it's 6% cheaper on average than a Monday, the most expensive day to book.* Get your timing right, and you can enjoy significant savings on domestic journeys.*Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC's global airline sales database.
Does Delta Air Lines fly nonstop from Louisville Intl. Airport (SDF) to Los Angeles - Ontario Intl. Airport (ONT)?
To find out if there's a direct trip from SDF to ONT with Delta Air Lines or another airline, use our "Nonstop" filter when browsing for tickets.
What is the earliest Delta Air Lines flight from SDF to ONT?
Sort your results by "Morning" and "Early Morning" to see the earliest flights from SDF to ONT. Jetting off early means flight cancellations are less likely.**Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
What airports does Delta Air Lines fly into in Ontario?
Jump on a Delta Air Lines flight from Louisville Intl. Airport (SDF) to Ontario, and you'll likely touch down at Los Angeles - Ontario Intl. Airport (ONT). This is the airline's main hub in this destination.
Why fly with Delta Air Lines from SDF to ONT?
Offering a rewarding loyalty program and an excellent in-flight experience, Delta Air Lines is a favorite for many travelers heading from SDF to ONT. Plus, if you're a Delta SkyMiles and One Key™ member booking with Expedia, you could earn OneKeyCash™* on eligible flights on top of your airline miles, which you can put toward future travel.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.
Can I change or cancel my Delta Air Lines flight from Louisville Intl. Airport (SDF) to Los Angeles - Ontario Intl. Airport (ONT)?
Changes are usually free within 24 hours of booking, but your airline may charge you after that. For further details about altering your reservation, head to your "Trips," select your flight and click on "Manage Booking." If you'd like the freedom to change your plans without additional charges, tick the "Changes included" and "No cancel fee" filters when planning your next break.

Explore a world of travel with Expedia

*Available to One Key members.