$162+ Cheap flights from Ontario to Louisville (ONT - SDF)
This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 5/17. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — SDF
May 19 — May 261
Round-trip
1 adult, Economy
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Cheapest flights from Ontario to LouisvilleExplore the most affordable flight options available from Ontario to Louisville. Find the lowest fares from popular airlines and budget airlines, with prices last updated on April 19, 2026.
Explore the most affordable flight options available from Ontario to Louisville. Find the lowest fares from popular airlines and budget airlines, with prices last updated on April 19, 2026.
This Delta deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/1310:00 pm
ONT
- SDF
1 stop7h 56m
Delta
Wed 5/206:00 am
SDF
- ONT
1 stop7h 57m
Delta
Deal found 4/14![Delta logo]()
$341
This Delta deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/1312:08 pm
ONT
- SDF
1 stop9h 17m
Delta
Tue 5/194:28 pm
SDF
- ONT
2 stops10h 06m
Delta
Deal found 4/16![Delta logo]()
$346
This Southwest deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/1911:55 pm
ONT
- SDF
1 stop6h 55m
Southwest
Sat 5/235:45 pm
SDF
- ONT
1 stop6h 00m
Southwest
Deal found 4/17![Southwest logo]()
$348
This American Airlines deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/132:08 pm
ONT
- SDF
1 stop6h 03m
American Airlines
Tue 5/195:41 pm
SDF
- ONT
1 stop7h 59m
American Airlines
Deal found 4/14![American Airlines logo]()
$350
This United Airlines deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/196:59 pm
ONT
- SDF
2 stops11h 26m
United Airlines
Sat 5/235:46 pm
SDF
- ONT
1 stop8h 05m
United Airlines
Deal found 4/17![United Airlines logo]()
$353
This Southwest deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/13:00 pm
ONT
- SDF
1 stop6h 15m
Southwest
Sat 6/67:55 pm
SDF
- ONT
1 stop5h 55m
Southwest
Deal found 4/16![Southwest logo]()
$355
This Delta deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/199:50 am
ONT
- SDF
2 stops11h 35m
Delta
Sat 5/234:28 pm
SDF
- ONT
2 stops9h 17m
Delta
Deal found 4/17![Delta logo]()
$358
This American Airlines deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/1111:59 pm
ONT
- SDF
1 stop7h 16m
American Airlines
Mon 5/187:55 pm
SDF
- ONT
1 stop6h 51m
American Airlines
Deal found 4/14![American Airlines logo]()
$380
This American Airlines deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/2611:59 pm
ONT
- SDF
1 stop7h 37m
American Airlines
Fri 5/296:02 pm
SDF
- ONT
1 stop8h 57m
American Airlines
Deal found 4/16![American Airlines logo]()
$381
This Southwest deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/2612:40 pm
ONT
- SDF
1 stop6h 50m
Southwest
Fri 5/292:40 pm
SDF
- ONT
2 stops9h 00m
Southwest
Deal found 4/16![Southwest logo]()
$386
Best flights from Ontario to LouisvilleDiscover carefully curated flight deals from Ontario to Louisville that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated April 19, 2026.
Discover carefully curated flight deals from Ontario to Louisville that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated April 19, 2026.
This Southwest deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/511:55 pm
ONT
- SDF
1 stop7h 05m
Southwest
Mon 6/85:05 pm
SDF
- ONT
1 stop8h 20m
Southwest
Deal found 4/14![Southwest logo]()
$406
This Delta deal was found by Cheapflights users on 4/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/2411:48 am
ONT
- SDF
1 stop9h 38m
Delta
Tue 7/286:00 am
SDF
- ONT
1 stop7h 38m
Delta
Deal found 4/18![Delta logo]()
$439
This United Airlines deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/305:00 am
ONT
- SDF
1 stop6h 23m
United Airlines
Mon 10/53:50 pm
SDF
- ONT
1 stop9h 08m
United Airlines
Deal found 4/17![United Airlines logo]()
$439
This United Airlines deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/61:40 pm
ONT
- SDF
1 stop5h 51m
United Airlines
Wed 5/133:36 pm
SDF
- ONT
1 stop9h 59m
United Airlines
Deal found 4/14![United Airlines logo]()
$441
This Southwest deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/101:20 pm
ONT
- SDF
1 stop7h 55m
Southwest
Sat 6/1312:30 pm
SDF
- ONT
1 stop8h 05m
Southwest
Deal found 4/15![Southwest logo]()
$449
This United Airlines deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/97:00 am
ONT
- SDF
1 stop8h 36m
United Airlines
Tue 5/123:36 pm
SDF
- ONT
1 stop9h 59m
United Airlines
Deal found 4/13![United Airlines logo]()
$448
This Delta deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/2510:00 pm
ONT
- SDF
1 stop7h 57m
Delta
Tue 6/307:05 am
SDF
- ONT
1 stop6h 35m
Delta
Deal found 4/14![Delta logo]()
$499
This Southwest deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/59:20 pm
ONT
- SDF
2 stops9h 40m
Southwest
Fri 10/96:00 am
SDF
- ONT
1 stop6h 25m
Southwest
Deal found 4/15![Southwest logo]()
$482
This Delta deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/235:45 pm
ONT
- SDF
2 stops13h 14m
Delta
Sun 5/316:05 am
SDF
- ONT
2 stops9h 14m
Delta
Deal found 4/16![Delta logo]()
$548
This Southwest deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/112:40 pm
ONT
- SDF
1 stop8h 35m
Southwest
Tue 5/56:40 pm
SDF
- ONT
1 stop6h 10m
Southwest
Deal found 4/16![Southwest logo]()
$577
This Delta deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/106:00 am
ONT
- SDF
2 stops8h 12m
Delta
Sun 5/174:28 pm
SDF
- ONT
2 stops10h 06m
Delta
Deal found 4/15![Delta logo]()
$578
Last-minute flights from Ontario to LouisvilleDiscover last-minute flight deals from Ontario to Louisville. Data last updated April 19, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to Louisville. Data last updated April 19, 2026 and is based on user searches.
This American Airlines deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/1111:59 pm
ONT
- SDF
1 stop7h 16m
American Airlines
Mon 5/187:55 pm
SDF
- ONT
1 stop6h 51m
American Airlines
Deal found 4/14![American Airlines logo]()
$380
This Delta deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/1310:00 pm
ONT
- SDF
1 stop7h 56m
Delta
Wed 5/206:00 am
SDF
- ONT
1 stop7h 57m
Delta
Deal found 4/14![Delta logo]()
$341
This Delta deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/1312:08 pm
ONT
- SDF
1 stop9h 17m
Delta
Tue 5/194:28 pm
SDF
- ONT
2 stops10h 06m
Delta
Deal found 4/16![Delta logo]()
$346
This American Airlines deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/132:08 pm
ONT
- SDF
1 stop6h 03m
American Airlines
Tue 5/195:41 pm
SDF
- ONT
1 stop7h 59m
American Airlines
Deal found 4/14![American Airlines logo]()
$350
This American Airlines deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/167:30 am
ONT
- SDF
1 stop6h 17m
American Airlines
Sun 5/245:43 pm
SDF
- ONT
1 stop7h 53m
American Airlines
Deal found 4/15![American Airlines logo]()
$388
This United Airlines deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/195:00 am
ONT
- SDF
1 stop6h 41m
United Airlines
Sat 5/235:46 pm
SDF
- ONT
1 stop8h 05m
United Airlines
Deal found 4/17![United Airlines logo]()
$348
This Delta deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/199:50 am
ONT
- SDF
2 stops11h 35m
Delta
Sat 5/234:28 pm
SDF
- ONT
2 stops9h 17m
Delta
Deal found 4/17![Delta logo]()
$358
This American Airlines deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/2611:59 pm
ONT
- SDF
1 stop7h 37m
American Airlines
Fri 5/296:02 pm
SDF
- ONT
1 stop8h 57m
American Airlines
Deal found 4/16![American Airlines logo]()
$381
This Southwest deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/2612:40 pm
ONT
- SDF
1 stop6h 50m
Southwest
Fri 5/292:40 pm
SDF
- ONT
2 stops9h 00m
Southwest
Deal found 4/16![Southwest logo]()
$386
This Delta deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/264:57 pm
ONT
- SDF
2 stops12h 59m
Delta
Fri 5/294:28 pm
SDF
- ONT
2 stops10h 06m
Delta
Deal found 4/16![Delta logo]()
$391
One-way flights from Ontario to LouisvilleSearch for one-way flight options from Ontario to Louisville. Find affordable one-way fares based on user searches. Data last updated April 19, 2026.
Search for one-way flight options from Ontario to Louisville. Find affordable one-way fares based on user searches. Data last updated April 19, 2026.
This Kiwi.com deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/178:06 pm
ONT
- SDF
2 stops19h 52m
Multiple Airlines
Deal found 4/17![Multiple Airlines logo]()
$162
This American Airlines deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/2611:59 pm
ONT
- SDF
1 stop7h 37m
American Airlines
Deal found 4/16![American Airlines logo]()
$171
This Southwest deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 6/63:00 pm
ONT
- SDF
1 stop7h 20m
Southwest
Deal found 4/16![Southwest logo]()
$178
This Delta deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/85:24 pm
ONT
- SDF
2 stops13h 31m
Delta
Deal found 4/14![Delta logo]()
$183
This Kiwi.com deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/268:06 pm
ONT
- SDF
3 stops58h 22m
Multiple Airlines
Deal found 4/16![Multiple Airlines logo]()
$185
This Kiwi.com deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/18:20 pm
ONT
- SDF
3 stops58h 08m
Multiple Airlines
Deal found 4/14![Multiple Airlines logo]()
$189
This Delta deal was found by Cheapflights users on 4/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/810:00 pm
ONT
- SDF
1 stop9h 29m
Delta
Deal found 4/18![Delta logo]()
$211
This Delta deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 6/66:00 am
ONT
- SDF
2 stops10h 50m
Delta
Deal found 4/16![Delta logo]()
$225
This United Airlines deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/91:40 pm
ONT
- SDF
1 stop5h 51m
United Airlines
Deal found 4/14![United Airlines logo]()
$228
This Delta deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/510:00 pm
ONT
- SDF
1 stop9h 20m
Delta
Deal found 4/17![Delta logo]()
$229
This Southwest deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/59:40 pm
ONT
- SDF
2 stops9h 20m
Southwest
Deal found 4/17![Southwest logo]()
$234
Find flight deals from Ontario to Louisville
Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) to Louisville (SDF). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated April 19, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $341 (Delta) |
One-way from | $162 (Kiwi.com) |
Popular in | January |
Cheapest in | July |
Average price | $479 |
Cheapflights Fare Finder
Customize your flight search to find flights from Ontario to Louisville that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated April 19, 2026.
Use the filters below to find and compare flights from Ontario to Louisville that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
OntarioLouisville
ONT - SDF
ONTSDF
Ontario
Fri 6/5
11:55 pm-10:00 am
1 stop7h 05m
Louisville Intl
Mon 6/8
5:05 pm-10:25 pm
1 stop8h 20m
$406
OntarioLouisville
ONT - SDF
ONTSDF
Ontario
Fri 7/24
11:48 am-12:26 am
1 stop9h 38m
Louisville Intl
Tue 7/28
6:00 am-10:38 am
1 stop7h 38m
$439
OntarioLouisville
ONT - SDF
ONTSDF
Ontario
Wed 9/30
5:00 am-2:23 pm
1 stop6h 23m
Louisville Intl
Mon 10/5
3:50 pm-9:58 pm
1 stop9h 08m
$439
OntarioLouisville
ONT - SDF
ONTSDF
Ontario
Wed 5/6
1:40 pm-10:31 pm
1 stop5h 51m
Louisville Intl
Wed 5/13
3:36 pm-10:35 pm
1 stop9h 59m
$441
OntarioLouisville
ONT - SDF
ONTSDF
Ontario
Sat 5/9
7:00 am-6:36 pm
1 stop8h 36m
Louisville Intl
Tue 5/12
3:36 pm-10:35 pm
1 stop9h 59m
$448
OntarioLouisville
ONT - SDF
ONTSDF
Ontario
Wed 6/10
1:20 pm-12:15 am
1 stop7h 55m
Louisville Intl
Sat 6/13
12:30 pm-5:35 pm
1 stop8h 05m
$449
OntarioLouisville
ONT - SDF
ONTSDF
Ontario
Mon 10/5
9:20 pm-10:00 am
2 stops9h 40m
Louisville Intl
Fri 10/9
6:00 am-9:25 am
1 stop6h 25m
$482
Quickest round-trip
OntarioLouisville
ONT - SDF
ONTSDF
Ontario
Thu 6/25
10:00 pm-8:57 am
1 stop7h 57m
Louisville Intl
Tue 6/30
7:05 am-10:40 am
1 stop6h 35m
$499
OntarioLouisville
ONT - SDF
ONTSDF
Ontario
Sat 5/23
5:45 pm-9:59 am
2 stops13h 14m
Louisville Intl
Sun 5/31
6:05 am-12:19 pm
2 stops9h 14m
$548
OntarioLouisville
ONT - SDF
ONTSDF
Ontario
Fri 5/1
12:40 pm-12:15 am
1 stop8h 35m
Louisville Intl
Tue 5/5
6:40 pm-9:50 pm
1 stop6h 10m
$577
Showing 1-10 of 20 resultsSorted by cheapest first
Compare providers for flights from Ontario to Louisville
Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Ontario to Louisville in April.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy1 star | Trust Score*3 stars |
- Most accurate provider: When it comes to deals on Ontario-Louisville flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Ontario-Louisville flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Ontario-Louisville flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on Ontario-Louisville flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Ontario-Louisville flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.
Best time to book a flight from Ontario to Louisville
Have a flexible travel schedule? Discover the best time to fly to Louisville from Ontario with our price prediction graph.
ONT-SDF
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.
Cheapflights Insights
Everything you need to know about your flight from Ontario to Louisville
What is the cheapest month to book a flight from Ontario to Louisville?
Currently, July is the cheapest month in which you can book a flight from Ontario to Louisville (average of $393). Flying from Ontario to Louisville in January is currently the most expensive (average of $976). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.
How much does it cost to fly round-trip from Ontario to Louisville?
Reviews of airlines servicing Louisville
Get insights into the airlines that provide service to Louisville. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Louisville. Reviews last updated April 19, 2026.
Read reviews from past customers who have flown Southwest,Delta, andUnited Airlines from Ontario to Louisville. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Entertainment
7.5
Food
7.0
Crew
8.6
Comfort
8.0
Overall
8.0
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Entertainment
7.5
Food
7.0
Crew
8.6
Comfort
8.0
Overall
8.0
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Entertainment
7.5
Food
7.0
Crew
8.6
Comfort
8.0
Overall
8.0
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Entertainment
7.5
Food
7.0
Crew
8.6
Comfort
8.0
Overall
8.0
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Entertainment
7.5
Food
7.0
Crew
8.6
Comfort
8.0
Overall
8.0
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Related info for your journey
Find useful and relevant information for your journey from Ontario to Louisville. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Traveling to a place near Louisville?
Book flights to Louisville if you plan to visit one of these locationsShepherdsville
Elizabethtown
Corydon
Jeffersonville
Bardstown
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Alternative routes for Ontario to Louisville
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Complete your trip
Complete your trip to Louisville by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Ontario to Louisville by cabin class
Find flights from Ontario to Louisville, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Other flights to Louisville
Explore flights to Louisville departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on April 19, 2026.
Ontario and Louisville flights
Browse other Ontario and Louisville flight options. Last updated on April 19, 2026.
Other flights from Ontario
Browse through other flights departing from Ontario. Flights are based on user searches made on Cheapflights and were last updated on April 19, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Top 4 airlines flying from Ontario to Louisville
Discover the top 4 airlines that operate flights from Ontario to Louisville. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated April 19, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$238 | Average$546 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$320 | Average$458 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$341 | Average$457 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$342 | Average$477 | FlexibilityNo cancel fee | On-time71% |