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$135+ 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 10/29. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — SDF
Nov 13 — Nov 201
Thu 11/13
Thu 11/20
1 adult, Economy
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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 October 14, 2025.

This Kiwi.com deal was found by Cheapflights users on 10/12. 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 11/137:22 amONT - SDF
2 stops22h 42mMultiple Airlines
Mon 11/179:43 amSDF - ONT
1 stop17h 07mMultiple Airlines
Deal found 10/12$334
This Delta deal was found by Cheapflights users on 10/11. 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 11/611:36 amONT - SDF
1 stop9h 25mDelta
Mon 11/106:16 pmSDF - ONT
1 stop7h 48mDelta
Deal found 10/11$351
This Southwest deal was found by Cheapflights users on 10/11. 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.
Thu 11/610:50 amONT - SDF
1 stop10h 25mSouthwest
Mon 11/105:30 amSDF - ONT
1 stop14h 45mSouthwest
Deal found 10/11$356
This Kiwi.com deal was found by Cheapflights users on 10/12. 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.
Sat 10/251:37 pmONT - SDF
1 stop21h 25mMultiple Airlines
Mon 10/279:43 amSDF - ONT
1 stop17h 29mMultiple Airlines
Deal found 10/12$358
This Delta deal was found by Cheapflights users on 10/13. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/1312:12 pmONT - SDF
1 stop8h 47mDelta
Mon 12/156:16 pmSDF - ONT
1 stop7h 48mDelta
Deal found 10/13$359
This American Airlines deal was found by Cheapflights users on 10/12. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/36:17 amONT - SDF
2 stops8h 55mAmerican Airlines
Thu 12/47:38 amSDF - ONT
2 stops11h 24mAmerican Airlines
Deal found 10/12$361
This Kiwi.com deal was found by Cheapflights users on 10/12. 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.
Sun 11/910:50 pmONT - SDF
1 stop18h 22mMultiple Airlines
Sun 11/167:11 pmSDF - ONT
2 stops26h 38mMultiple Airlines
Deal found 10/12$365
This Delta deal was found by Cheapflights users on 10/12. 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 10/2711:36 amONT - SDF
1 stop6h 07mDelta
Fri 10/313:00 pmSDF - ONT
2 stops9h 20mDelta
Deal found 10/12$367
This Southwest deal was found by Cheapflights users on 10/13. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/135:50 amONT - SDF
2 stops7h 00mSouthwest
Mon 12/151:50 pmSDF - ONT
2 stops9h 55mSouthwest
Deal found 10/13$369

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 October 14, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$334
(Kiwi.com)

One-way from

$135
(Trip.com)

Popular in

November

Cheapest in

February

Average price

$536
Provider with most accurate pricing for Ontario-Louisville Intl flight deals.
Search Deals
Provider most trusted by Cheapflights users for Ontario-Louisville Intl flights.
Search Deals
From Ontario to Louisville Intl
Search Deals
One-way flight from Ontario to Louisville Intl
Search Deals
Highest demand for flights based on searches. 11% potential increase in price ($60 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($8 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in October 2025
Search Deals

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 October 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

Wed 12/3

3:10 pm-11:45 pm

1 stop5h 35m

Louisville Intl

Thu 12/4

7:45 am-12:10 pm

1 stop7h 25m

$351

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Mon 10/27

11:36 am-8:43 pm

1 stop6h 07m

Louisville Intl

Fri 10/31

3:00 pm-9:20 pm

2 stops9h 20m

$367

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Sat 12/13

5:50 am-3:50 pm

2 stops7h 00m

Louisville Intl

Mon 12/15

1:50 pm-8:45 pm

2 stops9h 55m

$369

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Thu 11/6

11:36 am-12:01 am

1 stop9h 25m

Louisville Intl

Mon 11/10

6:03 pm-11:52 pm

2 stops8h 49m

$370

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Fri 10/31

1:29 pm-10:30 pm

1 stop6h 01m

Louisville Intl

Tue 11/4

8:00 am-5:34 pm

2 stops12h 34m

$410

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Thu 11/13

9:59 am-10:55 pm

2 stops9h 56m

Louisville Intl

Mon 11/17

10:51 am-6:20 pm

2 stops10h 29m

$414

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Fri 1/9

6:05 am-5:30 pm

2 stops8h 25m

Louisville Intl

Fri 1/16

6:25 am-10:40 am

1 stop7h 15m

$414

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Thu 11/6

5:35 am-7:15 pm

2 stops10h 40m

Louisville Intl

Mon 11/10

1:55 pm-7:40 pm

2 stops8h 45m

$458

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Thu 12/25

8:40 am-9:30 pm

2 stops9h 50m

Louisville Intl

Sun 12/28

6:20 am-12:40 pm

1 stop9h 20m

$460

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Tue 12/23

9:53 am-11:31 pm

2 stops10h 38m

Louisville Intl

Tue 12/30

8:12 pm-11:46 pm

1 stop6h 34m

$469

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/11

Showing 1-10 of 18 results
1
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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 October.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
PricelinePrice Accuracy1 starTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • 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.
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, June is the cheapest month in which you can book a flight from Ontario to Louisville (average of $71). Flying from Ontario to Louisville in November is currently the most expensive (average of $193). 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 October 14, 2025.

Unlike in the afternoon, when flights are generally more expensive, you can save up to 8% 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 October 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
4,238 reviews

Comfort

8.0

Boarding

8.1

Crew

8.6

Overall

8.0

Entertainment

7.5

Food

7.0

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
4,238 reviews
Southwest
8.0
Very good
4,238 reviews

Comfort

8.0

Boarding

8.1

Crew

8.6

Overall

8.0

Entertainment

7.5

Food

7.0

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
7,975 reviews
Southwest
8.0
Very good
4,238 reviews

Comfort

8.0

Boarding

8.1

Crew

8.6

Overall

8.0

Entertainment

7.5

Food

7.0

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
8,976 reviews
Southwest
8.0
Very good
4,238 reviews

Comfort

8.0

Boarding

8.1

Crew

8.6

Overall

8.0

Entertainment

7.5

Food

7.0

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
11,042 reviews
Southwest
8.0
Very good
4,238 reviews

Comfort

8.0

Boarding

8.1

Crew

8.6

Overall

8.0

Entertainment

7.5

Food

7.0

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.

  • How long is the flight from Ontario to Louisville?

    Airlines like Southwest and Delta fly from Ontario to Louisville in about 5h 35m. The time it takes to get you to your destination can typically vary by up to 32m. There are 1791 mi between Ontario and Louisville. This flight may include one or multiple stops.

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

    Flying on American Airlines is currently your cheapest option to Louisville, with prices starting at $342. Additional round-trip tickets that might be worth considering are offered by Southwest and United Airlines, with the lowest prices starting at $342 and $343, respectively. American Airlines is currently priced 28% 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, June is the cheapest month in which you can book a flight from Ontario to Louisville (average of $71). Flying from Ontario to Louisville in November is currently the most expensive (average of $193). 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 October 14, 2025.
AirlineCheapestAverageFlexibilityOn-time
SouthwestCheapest$342Average$461FlexibilityNo cancel feeOn-time63%
American AirlinesCheapest$342Average$516FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$343Average$506FlexibilityNo cancel feeOn-time69%
DeltaCheapest$346Average$507FlexibilityNo cancel feeOn-timeN/A

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