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$172+ 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 6/4. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — SDF
may. 17 — may. 241
sáb. 5/17
sáb. 5/24
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 mayo 12, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

Expedia
3 stars

Round-trip from

$345
(American Airlines)

One-way from

$172
(American Airlines)

Popular in

March

Cheapest in

August

Average price

$517
Provider with most accurate pricing for Ontario-Louisville Intl flight deals.
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Provider most trusted by Cheapflights users for Ontario-Louisville Intl flights.
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From Ontario to Louisville Intl
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One-way flight from Ontario to Louisville Intl
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High demand for flights, 7% potential price rise
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Cheapest flight prices on average. 1% potential price decrease ($7 potential savings vs. average RT price).
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Average for round-trip flights in May 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 mayo 12, 2025.

This American Airlines deal was found by Cheapflights users on 5/11. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 6/1010:54 amONT - SDF
1 stop8h 53mAmerican Airlines
sáb. 6/148:27 pmSDF - ONT
1 stop6h 32mAmerican Airlines
Deal found 5/11$345
This Delta deal was found by Cheapflights users on 5/11. 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.
jue. 10/210:59 pmONT - SDF
1 stop7h 52mDelta
lun. 10/65:45 pmSDF - ONT
1 stop7h 56mDelta
Deal found 5/11$374
This Southwest deal was found by Cheapflights users on 5/11. 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.
jue. 7/34:10 pmONT - SDF
1 stop6h 35mSouthwest
sáb. 7/127:05 pmSDF - ONT
1 stop7h 05mSouthwest
Deal found 5/11$408
This United Airlines deal was found by Cheapflights users on 5/11. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 5/265:10 amONT - SDF
1 stop6h 21mUnited Airlines
vie. 5/308:00 amSDF - ONT
1 stop7h 31mUnited Airlines
Deal found 5/11$432
This Alaska Airlines deal was found by Cheapflights users on 5/11. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 5/317:30 amONT - SDF
2 stops13h 53mAlaska Airlines
vie. 6/612:40 pmSDF - ONT
2 stops14h 17mAlaska Airlines
Deal found 5/11$597

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 mayo 12, 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

mar. 6/10

10:54 am-10:47 pm

1 stop8h 53m

Louisville Intl

sáb. 6/14

8:27 pm-11:59 pm

1 stop6h 32m

$345

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

jue. 10/2

10:59 pm-9:51 am

1 stop7h 52m

Louisville Intl

lun. 10/6

5:45 pm-10:41 pm

1 stop7h 56m

$374

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

jue. 7/3

4:10 pm-1:45 am

1 stop6h 35m

Louisville Intl

sáb. 7/12

7:05 pm-11:10 pm

1 stop7h 05m

$408

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

lun. 5/26

5:10 am-2:31 pm

1 stop6h 21m

Louisville Intl

vie. 5/30

8:00 am-12:31 pm

1 stop7h 31m

$432

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

sáb. 5/31

7:30 am-12:23 am

2 stops13h 53m

Louisville Intl

vie. 6/6

12:40 pm-11:57 pm

2 stops14h 17m

$597

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

mié. 6/4

12:45 pm-12:23 am

1 stop8h 38m

$172

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

lun. 6/16

6:41 pm-9:33 am

2 stops11h 52m

$214

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

dom. 6/1

7:20 pm-10:58 am

2 stops12h 38m

$320

Flights are sorted by cheapest round-trip flights first.

Deals found on 5/11

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 May.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*2 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 Expedia the most. Expedia 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, 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 mayo 12, 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.

Rainfall in Louisville by month

Plan your trip to Louisville by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Louisville ranges from 3.1 - 5.3 inches per month. May is typically the wettest month, when rainfall can reach 5.3 in. September is typically the driest time to visit Louisville when rainfall is around 3.1 in.

Temperature in Louisville by month

Plan your trip to Louisville by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Louisville, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 78.8 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 35.6 F).

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 mayo 12, 2025.
Read reviews from past customers who have flown Alaska Airlines, Southwest and Delta from Ontario to Louisville. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Food

7.1

Comfort

7.9

Entertainment

7.1

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Alaska Airlines
8.0
Very good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Food

7.1

Comfort

7.9

Entertainment

7.1

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Southwest
8.0
Very good
4,290 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Food

7.1

Comfort

7.9

Entertainment

7.1

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Delta
8.0
Very good
7,950 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Food

7.1

Comfort

7.9

Entertainment

7.1

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
United Airlines
7.4
Good
8,724 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Food

7.1

Comfort

7.9

Entertainment

7.1

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
American Airlines
7.2
Good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Food

7.1

Comfort

7.9

Entertainment

7.1

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

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 American Airlines is currently your cheapest option to Louisville, with prices starting at $345. Additional round-trip tickets that might be worth considering are offered by Delta and Southwest, with the lowest prices starting at $374 and $408, respectively. American Airlines is currently priced 27% below the average price you’ll pay for this route.

  • What are the cheapest airlines to fly from Ontario to Louisville one-way?

    To fly one-way, consider booking your trip with American Airlines, which is currently one of the cheapest options available, starting at $172. United Airlines flights start at $214 while deals on Alaska Airlines start at $320 one-way.

  • 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 Ontario?

Book flights to Ontario if you plan to visit one of these locations
Jeffersonville
Corydon
Elizabethtown
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 mayo 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$326Average$496FlexibilityNo cancel feeOn-time71%
DeltaCheapest$346Average$416FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$354Average$505FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$367Average$477FlexibilityNo cancel feeOn-time63%

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