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Ontario

$161+ Cheap flights from Louisville to Ontario (SDF - ONT)

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 4/21. Fares are subject to change and may not be available on all flights or dates of travel.
SDF — ONT
Apr 9 — Apr 161
Thu 4/9
Thu 4/16
1 adult, Economy
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Cheap flight deals from Louisville to Ontario

Cheapest flights from Louisville to Ontario
Explore the most affordable flight options available from Louisville to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 10, 2026.

This Southwest deal was found by Cheapflights users on 3/8. 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 4/74:40 pm
SDF
-
ONT
1 stop6h 55m
Southwest
Tue 4/1411:55 pm
ONT
-
SDF
1 stop6h 55m
Southwest
Deal found 3/8$321
This Delta deal was found by Cheapflights users on 3/8. 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 4/146:00 am
SDF
-
ONT
1 stop8h 36m
Delta
Wed 4/1512:49 pm
ONT
-
SDF
1 stop8h 10m
Delta
Deal found 3/8$335
This Delta deal was found by Cheapflights users on 3/10. 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 5/283:29 pm
SDF
-
ONT
1 stop9h 19m
Delta
Tue 6/910:59 pm
ONT
-
SDF
1 stop6h 46m
Delta
Deal found 3/10$338
This Southwest deal was found by Cheapflights users on 3/8. 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 4/1612:20 pm
SDF
-
ONT
1 stop7h 05m
Southwest
Mon 4/209:55 pm
ONT
-
SDF
2 stops8h 55m
Southwest
Deal found 3/8$340
This American Airlines deal was found by Cheapflights users on 3/8. 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 4/217:36 am
SDF
-
ONT
2 stops11h 46m
American Airlines
Wed 4/2212:19 pm
ONT
-
SDF
2 stops8h 29m
American Airlines
Deal found 3/8$345
This Delta deal was found by Cheapflights users on 3/10. 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 5/283:29 pm
SDF
-
ONT
1 stop9h 19m
Delta
Mon 6/810:59 pm
ONT
-
SDF
1 stop6h 46m
Delta
Deal found 3/10$355
This Delta deal was found by Cheapflights users on 3/9. 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 5/126:00 am
SDF
-
ONT
1 stop7h 57m
Delta
Sat 5/167:05 am
ONT
-
SDF
1 stop6h 56m
Delta
Deal found 3/9$370
This Delta deal was found by Cheapflights users on 3/8. 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 4/112:00 pm
SDF
-
ONT
1 stop10h 00m
Delta
Wed 4/1512:49 pm
ONT
-
SDF
1 stop8h 10m
Delta
Deal found 3/8$377
This Delta deal was found by Cheapflights users on 3/9. 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 5/126:00 am
SDF
-
ONT
1 stop7h 57m
Delta
Fri 5/1510:00 pm
ONT
-
SDF
1 stop9h 20m
Delta
Deal found 3/9$379
This Southwest deal was found by Cheapflights users on 3/5. 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 5/208:25 am
SDF
-
ONT
1 stop6h 30m
Southwest
Wed 5/279:45 pm
ONT
-
SDF
2 stops9h 10m
Southwest
Deal found 3/5$384

Find flight deals from Louisville to Ontario

Discover tips and strategies to find the most affordable flight options for your journey from Louisville (SDF) to Ontario (ONT). 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 March 10, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$321
(Southwest)

One-way from

$161
(Delta)

Popular in

December

Cheapest in

October

Average price

$359
Provider with most accurate pricing for Louisville Intl-Ontario flight deals.
Search Deals
Provider most trusted by Cheapflights users for Louisville Intl-Ontario flights.
Search Deals
From Louisville Intl to Ontario
Search Deals
One-way flight from Louisville Intl to Ontario
Search Deals
Highest demand for flights based on searches. 17% potential increase in price ($90 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease ($17 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in March 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Louisville to Ontario 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 March 10, 2026.
Use the filters below to find and compare flights from Louisville to Ontario that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

LouisvilleOntario

SDF - ONT

SDFONT

Louisville Intl

Sat 5/9

4:25 pm-10:00 pm

1 stop8h 35m

Ontario

Thu 5/14

12:40 pm-12:15 am

1 stop8h 35m

$335

LouisvilleOntario

SDF - ONT

SDFONT

Louisville Intl

Sat 5/9

9:00 am-12:38 pm

1 stop6h 38m

Ontario

Thu 5/14

6:59 pm-9:25 am

2 stops11h 26m

$340

LouisvilleOntario

SDF - ONT

SDFONT

Louisville Intl

Sat 5/16

3:30 pm-9:58 pm

1 stop9h 28m

Ontario

Sat 5/23

6:30 am-7:02 pm

1 stop9h 32m

$425
Quickest round-trip

LouisvilleOntario

SDF - ONT

SDFONT

Louisville Intl

Tue 3/31

3:36 pm-8:36 pm

1 stop8h 00m

Ontario

Wed 4/1

1:34 pm-10:39 pm

1 stop6h 05m

$425

LouisvilleOntario

SDF - ONT

SDFONT

Louisville Intl

Wed 4/15

4:42 pm-11:44 pm

2 stops10h 02m

Ontario

Sun 4/19

10:15 pm-10:26 am

1 stop9h 11m

$443

LouisvilleOntario

SDF - ONT

SDFONT

Louisville Intl

Wed 5/13

3:30 pm-9:58 pm

1 stop9h 28m

Ontario

Sun 5/17

5:00 am-2:41 pm

1 stop6h 41m

$469

LouisvilleOntario

SDF - ONT

SDFONT

Louisville Intl

Wed 4/1

9:00 am-5:47 pm

2 stops11h 47m

Ontario

Sat 4/4

1:34 pm-10:39 pm

1 stop6h 05m

$492

LouisvilleOntario

SDF - ONT

SDFONT

Louisville Intl

Sun 5/31

3:29 pm-9:48 pm

1 stop9h 19m

Ontario

Mon 8/3

10:59 pm-1:38 pm

2 stops11h 39m

$513

LouisvilleOntario

SDF - ONT

SDFONT

Louisville Intl

Wed 4/1

10:00 am-8:36 pm

2 stops13h 36m

Ontario

Fri 4/3

1:43 pm-10:39 pm

1 stop5h 56m

$514
Cheapest one-way

LouisvilleOntario

SDF - ONT

SDFONT

Louisville Intl

Sun 4/19

8:14 pm-10:44 am

3 stops41h 30m

$200

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/5

Showing 1-10 of 20 resultsSorted by cheapest first
1
2

Compare providers for flights from Louisville to Ontario

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 Louisville to Ontario in March.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust 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 Louisville-Ontario flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Louisville-Ontario flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Louisville-Ontario flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Louisville-Ontario 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 Louisville-Ontario 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 Louisville to Ontario

Have a flexible travel schedule? Discover the best time to fly to Ontario from Louisville 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 Louisville to Ontario

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

Currently, May is the cheapest month in which you can book a flight from Louisville to Ontario (average of $97). Flying from Louisville to Ontario in March is currently the most expensive (average of $200). 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.

Reviews of airlines servicing Ontario

Get insights into the airlines that provide service to Ontario. 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 Ontario. Reviews last updated March 10, 2026.
Get a feel of what it's like to fly with Southwest,United Airlines, andAmerican Airlines from Louisville to Ontario by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,317 reviews

Crew

8.6

Overall

8.0

Boarding

8.1

Food

7.0

Entertainment

7.5

Comfort

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
4,317 reviews
Southwest
8.0
Very good
4,317 reviews

Crew

8.6

Overall

8.0

Boarding

8.1

Food

7.0

Entertainment

7.5

Comfort

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
9,409 reviews
Southwest
8.0
Very good
4,317 reviews

Crew

8.6

Overall

8.0

Boarding

8.1

Food

7.0

Entertainment

7.5

Comfort

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
7.1
Good
11,414 reviews
Southwest
8.0
Very good
4,317 reviews

Crew

8.6

Overall

8.0

Boarding

8.1

Food

7.0

Entertainment

7.5

Comfort

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 Louisville to Ontario. 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 Louisville to Ontario?

    Southwest and United Airlines can get you from Louisville to Ontario in just under 6h 38m. Your travel time can differ by up to 1h 57m. Airlines will cover a distance of 1791 mi. Both multi-stop and nonstop flights can be found to your destination and back.

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

    American Airlines, at $268, was found to be the cheapest airline from Louisville to Ontario.Alternate airlines to your destination round-trip include Southwest and United Airlines. American Airlines is currently priced 36% below the average price you’ll pay for this route.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Louisville to Ontario 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 Louisville to Ontario?

    Currently, May is the cheapest month in which you can book a flight from Louisville to Ontario (average of $97). Flying from Louisville to Ontario in March is currently the most expensive (average of $200). 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

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Top 3 airlines flying from Louisville to Ontario

Discover the top 3 airlines that operate flights from Louisville to Ontario. 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 March 10, 2026.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$268Average$428FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$302Average$400FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$344Average$607FlexibilityNo cancel feeOn-time69%

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