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$110+ 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 9/10. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — SDF
Aug 19 — Aug 261
Tue 8/19
Tue 8/26
1 adult, Economy
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Cheap 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 August 14, 2025.

Round-trip from

$251
(Kiwi.com)

One-way from

$110
(Trip.com)

Popular in

November

Cheapest in

August

Average price

$354
From Ontario to Louisville Intl
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One-way flight from Ontario to Louisville Intl
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Highest demand for flights based on searches. 13% potential increase in price ($71 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($9 potential savings vs. average RT price).
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Average for round-trip flights in August 2025
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Find flight deals from Ontario to Louisville

Cheapest flights from Ontario to Louisville
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 August 14, 2025.

This Kiwi.com deal was found by Cheapflights users on 8/14. 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 11/76:00 amONT - SDF
1 stop7h 12mMultiple Airlines
Mon 11/105:20 pmSDF - ONT
1 stop7h 35mMultiple Airlines
Deal found 8/14$251
This Delta deal was found by Cheapflights users on 8/12. 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 9/911:45 amONT - SDF
1 stop6h 29mDelta
Wed 9/106:00 amSDF - ONT
1 stop7h 35mDelta
Deal found 8/12$277
This United Airlines deal was found by Cheapflights users on 8/13. 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.
Tue 9/97:00 amONT - SDF
2 stops12h 57mUnited Airlines
Tue 9/169:31 amSDF - ONT
1 stop6h 01mUnited Airlines
Deal found 8/13$282
This American Airlines deal was found by Cheapflights users on 8/13. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/96:10 amONT - SDF
2 stops10h 53mAmerican Airlines
Tue 9/1610:00 amSDF - ONT
2 stops11h 16mAmerican Airlines
Deal found 8/13$287
This Delta deal was found by Cheapflights users on 8/12. 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 9/811:45 amONT - SDF
1 stop9h 11mDelta
Tue 9/167:10 amSDF - ONT
1 stop6h 32mDelta
Deal found 8/12$297
This Delta deal was found by Cheapflights users on 8/12. 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 9/711:45 amONT - SDF
1 stop6h 29mDelta
Wed 9/106:00 amSDF - ONT
1 stop7h 35mDelta
Deal found 8/12$307
This Delta deal was found by Cheapflights users on 8/14. 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 9/411:45 amONT - SDF
1 stop9h 11mDelta
Sat 9/66:00 amSDF - ONT
1 stop7h 35mDelta
Deal found 8/14$317
This Kiwi.com deal was found by Cheapflights users on 8/12. 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.
Thu 9/187:30 pmONT - SDF
1 stop16h 50mMultiple Airlines
Sun 9/214:20 pmSDF - ONT
1 stop8h 03mMultiple Airlines
Deal found 8/12$318
This American Airlines deal was found by Cheapflights users on 8/14. 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.
Thu 9/46:10 amONT - SDF
2 stops12h 26mAmerican Airlines
Mon 9/86:44 pmSDF - ONT
1 stop6h 49mAmerican Airlines
Deal found 8/14$322
This Kiwi.com deal was found by Cheapflights users on 8/13. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/2912:13 pmONT - SDF
2 stops18h 06mMultiple Airlines
Fri 10/34:20 pmSDF - ONT
1 stop8h 35mMultiple Airlines
Deal found 8/13$326
This Delta deal was found by Cheapflights users on 8/14. 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 9/411:45 amONT - SDF
1 stop6h 29mDelta
Fri 9/57:10 amSDF - ONT
1 stop6h 25mDelta
Deal found 8/14$327

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 August 14, 2025.
Use the filters below to find and compare flights from Ontario to Louisville that are best for you.

Fly from

Ontario

Fly to

Louisville

Route

Depart

Return

Price

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Fri 11/7

6:00 am-4:12 pm

1 stop7h 12m

Louisville Intl

Mon 11/10

5:20 pm-9:55 pm

1 stop7h 35m

$251

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Tue 9/16

11:55 am-11:52 pm

1 stop8h 57m

Louisville Intl

Tue 9/23

7:10 am-10:42 am

1 stop6h 32m

$277

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Tue 9/9

7:00 am-6:58 pm

1 stop8h 58m

Louisville Intl

Tue 9/16

3:35 pm-9:25 pm

1 stop8h 50m

$277

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Tue 9/9

11:45 am-9:14 pm

1 stop6h 29m

Louisville Intl

Wed 9/10

6:00 am-10:35 am

1 stop7h 35m

$277

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Tue 9/9

11:45 am-9:14 pm

1 stop6h 29m

Louisville Intl

Tue 9/16

7:10 am-10:42 am

1 stop6h 32m

$277

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Tue 9/16

11:55 am-9:13 pm

1 stop6h 18m

Louisville Intl

Wed 9/17

7:10 am-10:42 am

1 stop6h 32m

$277

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Tue 9/9

6:10 am-8:03 pm

2 stops10h 53m

Louisville Intl

Tue 9/16

10:00 am-6:16 pm

2 stops11h 16m

$287

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Sat 10/11

11:59 pm-12:02 pm

1 stop9h 03m

Louisville Intl

Wed 10/15

9:44 am-1:43 pm

1 stop6h 59m

$297

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Thu 9/11

10:00 pm-8:49 am

1 stop7h 49m

Louisville Intl

Tue 9/16

7:10 am-10:42 am

1 stop6h 32m

$297

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Tue 9/9

11:45 am-9:14 pm

1 stop6h 29m

Louisville Intl

Sat 9/13

12:48 pm-7:15 pm

1 stop9h 27m

$297

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/13

Showing 1-10 of 21 results
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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.
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, January is the cheapest month in which you can book a flight from Ontario to Louisville (average of $299). Flying from Ontario to Louisville in April is currently the most expensive (average of $369). 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.

What is the cheapest time of day to fly from ONT to SDF?

Find hourly flight availability from Ontario to Louisville. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated August 14, 2025.

Unlike in the afternoon, when flights are generally more expensive, you can save up to 9% on flights from Ontario to Louisville by exploring options for tickets in the evening.

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 August 14, 2025.
Read reviews from past customers who have flown Southwest, Delta, and United 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.
Southwest
8.0
Very good
4,244 reviews

Crew

8.6

Boarding

8.1

Food

7.0

Comfort

8.0

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Southwest
8.0
Very good
4,244 reviews
Southwest
8.0
Very good
4,244 reviews

Crew

8.6

Boarding

8.1

Food

7.0

Comfort

8.0

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Delta
8.0
Very good
7,980 reviews
Southwest
8.0
Very good
4,244 reviews

Crew

8.6

Boarding

8.1

Food

7.0

Comfort

8.0

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
United Airlines
7.4
Good
8,916 reviews
Southwest
8.0
Very good
4,244 reviews

Crew

8.6

Boarding

8.1

Food

7.0

Comfort

8.0

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
American Airlines
7.2
Good
10,000 reviews
Southwest
8.0
Very good
4,244 reviews

Crew

8.6

Boarding

8.1

Food

7.0

Comfort

8.0

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.

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.

  • What are the cheapest airlines flying from Ontario to Louisville round-trip?

    Flying on Delta is currently your cheapest option to Louisville, with prices starting at $326. Additional round-trip tickets that might be worth considering are offered by American Airlines and Southwest, with the lowest prices starting at $338 and $342, respectively. Delta is currently priced 31% below the average price you’ll pay for this route.

  • Can I find deals for flights from Ontario to Louisville that include hotel bookings?

    Yes. In addition to deals on Ontario to Louisville flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Ontario to Louisville?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Ontario to Louisville.

  • Can I find deals for business class flights from Ontario to Louisville?

    Yes. Cheapflights offers flight deals from Ontario to Louisville by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Ontario to Louisville?

    Currently, January is the cheapest month in which you can book a flight from Ontario to Louisville (average of $299). Flying from Ontario to Louisville in April is currently the most expensive (average of $369). 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.

See more FAQs

Traveling to a place near Louisville?

Book flights to Louisville if you plan to visit one of these locations
Shepherdsville
Jeffersonville
Elizabethtown
Corydon
Bardstown

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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 August 14, 2025.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$326Average$466FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$338Average$517FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$342Average$464FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$378Average$556FlexibilityNo cancel feeOn-time69%

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