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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 8/4. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — SDF
Jul 7 — Jul 141
Mon 7/7
Mon 7/14
1 adult, Economy
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Cheapflights Tip: The best prices from Ontario to Louisville Intl are usually found in August or February, booked 67 days in advance, depart on a Saturday or Friday and return on a Thursday

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 July 2, 2025.

Round-trip from

$343
(American Airlines)

One-way from

$172
(American Airlines)

Popular in

March

Cheapest in

August

Average price

$416
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, 6% potential price rise
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Cheapest flight prices on average. 1% potential price decrease ($8 potential savings vs. average RT price).
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Average for round-trip flights in July 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 July 2, 2025.

This American Airlines deal was found by Cheapflights users on 6/30. 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 10/212:45 pmONT - SDF
1 stop7h 49mAmerican Airlines
Mon 10/66:17 pmSDF - ONT
1 stop8h 58mAmerican Airlines
Deal found 6/30$343
This Southwest deal was found by Cheapflights users on 6/30. 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 8/215:20 amONT - SDF
1 stop7h 10mSouthwest
Sun 8/246:20 amSDF - ONT
1 stop6h 15mSouthwest
Deal found 6/30$366
This United Airlines deal was found by Cheapflights users on 6/30. 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.
Fri 8/225:10 amONT - SDF
1 stop6h 24mUnited Airlines
Sun 8/243:30 pmSDF - ONT
1 stop8h 13mUnited Airlines
Deal found 6/30$384
This Delta deal was found by Cheapflights users on 6/30. 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 7/2711:40 amONT - SDF
1 stop9h 52mDelta
Tue 8/57:05 amSDF - ONT
1 stop6h 25mDelta
Deal found 6/30$430
This Alaska Airlines deal was found by Cheapflights users on 7/1. 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.
Tue 9/167:10 amONT - SDF
2 stops13h 30mAlaska Airlines
Tue 9/2310:00 amSDF - ONT
2 stops11h 36mAlaska Airlines
Deal found 7/1$447

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 July 2, 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

Thu 8/7

10:50 am-7:59 pm

1 stop6h 09m

Louisville Intl

Mon 8/11

10:00 am-1:39 pm

1 stop6h 39m

$343

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Thu 8/21

5:10 am-2:34 pm

1 stop6h 24m

Louisville Intl

Sun 8/24

3:30 pm-8:43 pm

1 stop8h 13m

$361

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Thu 8/21

5:20 am-3:30 pm

1 stop7h 10m

Louisville Intl

Sun 8/24

6:20 am-9:35 am

1 stop6h 15m

$366

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Sun 7/27

11:40 am-12:32 am

1 stop9h 52m

Louisville Intl

Tue 8/5

7:05 am-10:30 am

1 stop6h 25m

$430

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Tue 9/16

7:10 am-11:40 pm

2 stops13h 30m

Louisville Intl

Tue 9/23

10:00 am-6:36 pm

2 stops11h 36m

$447

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Mon 8/4

12:59 am-12:07 pm

1 stop8h 08m

$172

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Sun 9/21

2:05 pm-1:55 am

1 stop8h 50m

$195

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Sun 8/3

7:05 am-7:09 pm

1 stop9h 04m

$209

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Wed 8/20

5:10 am-2:34 pm

1 stop6h 24m

$212

OntarioLouisville

ONT - SDF

ONTSDF

Ontario

Tue 8/26

6:00 am-8:02 pm

2 stops11h 02m

$259

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/29

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

How far ahead should I book a flight from Ontario to Louisville?

Use this chart to determine the optimal time to book a round-trip flight from Ontario to Louisville. Price data was last updated on June 27, 2025.

Booking 67 days in advance of your planned departure date is, on average, the best time to get cheap flights from Ontario to Louisville. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

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 July 2, 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.

Weekly flight availability from Ontario to Louisville

Explore weekly flight availability from Ontario to Louisville. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated July 2, 2025.

The most flights from ONT to SDF are scheduled on a Monday (2 on average). You will have fewer flight options on Friday, which is when the least amount of flights are scheduled (1 on average).

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 July 2, 2025.
Read reviews from past customers who have flown Alaska Airlines, Southwest, and Delta 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.
Alaska Airlines
8.0
Very good
10,000 reviews

Crew

8.5

Overall

8.0

Boarding

8.1

Food

7.1

Comfort

7.8

Entertainment

7.1

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

Crew

8.5

Overall

8.0

Boarding

8.1

Food

7.1

Comfort

7.8

Entertainment

7.1

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
4,272 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Crew

8.5

Overall

8.0

Boarding

8.1

Food

7.1

Comfort

7.8

Entertainment

7.1

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
7,983 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Crew

8.5

Overall

8.0

Boarding

8.1

Food

7.1

Comfort

7.8

Entertainment

7.1

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
8,861 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Crew

8.5

Overall

8.0

Boarding

8.1

Food

7.1

Comfort

7.8

Entertainment

7.1

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

Crew

8.5

Overall

8.0

Boarding

8.1

Food

7.1

Comfort

7.8

Entertainment

7.1

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 airports do I use to fly from Ontario to Louisville?

    Louisville Intl is the airport most travelers will use when flying to Louisville from Ontario. Booking flights from Ontario (ONT) to Louisville Intl (SDF) should be relatively easy as there is 1 daily flight to Louisville from 4 different airlines. 5h 39m is how long a flight from Ontario to Louisville Intl will take if you book a nonstop flight.

  • 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 $343. Additional round-trip tickets that might be worth considering are offered by Southwest and United Airlines, with the lowest prices starting at $366 and $384, 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. Southwest flights start at $195 while deals on Delta start at $209 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
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 July 2, 2025.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$326Average$416FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$326Average$496FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$354Average$505FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$367Average$472FlexibilityNo cancel feeOn-time63%

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