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$172+ 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 5/26. Fares are subject to change and may not be available on all flights or dates of travel.
SDF — ONT
May 6 — May 131
Tue 5/6
Tue 5/13
1 adult, Economy
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Cheap 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 May 1, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$307
(Delta)

One-way from

$172
(Delta)

Popular in

May

Cheapest in

August

Average price

$937
Provider with most accurate pricing for Louisville Intl-Ontario flight deals.
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Provider most trusted by Cheapflights users for Louisville Intl-Ontario flights.
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From Louisville Intl to Ontario
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One-way flight from Louisville Intl to Ontario
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Highest demand for flights based on searches. 15% potential increase in price ($104 potential increase over avg. RT price).
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Cheapest flight prices on average. 7% potential price decrease ($36 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 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 May 1, 2025.

This Delta deal was found by Cheapflights users on 4/29. 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 8/56:00 amSDF - ONT
1 stop7h 30mDelta
Wed 8/610:05 pmONT - SDF
1 stop8h 43mDelta
Deal found 4/29$307
This United Airlines deal was found by Cheapflights users on 4/29. 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.
Wed 6/118:00 amSDF - ONT
1 stop7h 31mUnited Airlines
Tue 6/176:41 pmONT - SDF
2 stops11h 52mUnited Airlines
Deal found 4/29$312
This Southwest deal was found by Cheapflights users on 4/29. 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 7/16:05 pmSDF - ONT
1 stop5h 55mSouthwest
Mon 7/712:55 pmONT - SDF
2 stops8h 30mSouthwest
Deal found 4/29$357
This American Airlines deal was found by Cheapflights users on 4/29. 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.
Sat 8/212:38 pmSDF - ONT
2 stops8h 30mAmerican Airlines
Wed 8/66:17 amONT - SDF
2 stops10h 45mAmerican Airlines
Deal found 4/29$427
This Alaska Airlines deal was found by Cheapflights users on 4/30. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/215:45 amSDF - ONT
2 stops13h 05mAlaska Airlines
Sat 5/316:00 amONT - SDF
2 stops12h 03mAlaska Airlines
Deal found 4/30$552

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 May 1, 2025.
Use the filters below to find and compare flights from Louisville to Ontario that are best for you.

Fly from

Louisville

Fly to

Ontario

Route

Depart

Return

Price

LouisvilleOntario

SDF - ONT

SDFONT

Louisville Intl

Tue 8/5

6:00 am-10:30 am

1 stop7h 30m

Ontario

Wed 8/6

10:05 pm-9:48 am

1 stop8h 43m

$307

LouisvilleOntario

SDF - ONT

SDFONT

Louisville Intl

Wed 6/11

8:00 am-12:31 pm

1 stop7h 31m

Ontario

Tue 6/17

6:41 pm-9:33 am

2 stops11h 52m

$312

LouisvilleOntario

SDF - ONT

SDFONT

Louisville Intl

Tue 7/1

6:05 pm-9:00 pm

1 stop5h 55m

Ontario

Mon 7/7

12:55 pm-12:25 am

2 stops8h 30m

$357

LouisvilleOntario

SDF - ONT

SDFONT

Louisville Intl

Sat 8/2

12:38 pm-6:08 pm

2 stops8h 30m

Ontario

Wed 8/6

6:17 am-8:02 pm

2 stops10h 45m

$427

LouisvilleOntario

SDF - ONT

SDFONT

Louisville Intl

Wed 5/21

5:45 am-3:50 pm

2 stops13h 05m

Ontario

Sat 5/31

6:00 am-9:03 pm

2 stops12h 03m

$552

LouisvilleOntario

SDF - ONT

SDFONT

Louisville Intl

Mon 5/26

6:00 am-11:08 am

1 stop8h 08m

$172

LouisvilleOntario

SDF - ONT

SDFONT

Louisville Intl

Thu 5/22

6:00 am-9:58 am

1 stop6h 58m

$199

LouisvilleOntario

SDF - ONT

SDFONT

Louisville Intl

Wed 6/4

3:29 pm-10:45 pm

2 stops10h 16m

$204

LouisvilleOntario

SDF - ONT

SDFONT

Louisville Intl

Mon 6/2

5:45 am-3:50 pm

2 stops13h 05m

$259

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/30

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 May.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*2 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
PricelinePrice Accuracy2 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 eDreams the most. eDreams 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, August is the cheapest month in which you can book a flight from Louisville to Ontario (average of $246). Flying from Louisville to Ontario in March is currently the most expensive (average of $328). 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 SDF to ONT?

Find hourly flight availability from Louisville to Ontario. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated May 1, 2025.

When flying from Louisville to Ontario, the time of day you fly usually plays a role in the price. Save by searching for a flight in the evening, which can drop the price by up to 38% versus a flight at noon.

Rainfall in Ontario by month

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

In terms of precipitation, rainfall in Ontario ranges from 0.1 - 3.4 inches per month. February is typically the wettest month, when rainfall can reach 3.4 in. June is typically the driest time to visit Ontario when rainfall is around 0.1 in.

Temperature in Ontario by month

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

If weather is an important factor for your trip to Ontario, use this chart to help with planning. For those seeking warmer temperatures, August 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 December, when temperatures are typically at their lowest (around 53.6 F).

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 May 1, 2025.
Peruse reviews from past customers who have flown with Alaska Airlines, Southwest and Delta from Louisville to Ontario to help guide your decision. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
9,968 reviews

Food

7.1

Boarding

8.2

Crew

8.5

Entertainment

7.1

Comfort

7.9

Overall

8.0

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
9,968 reviews
Alaska Airlines
8.0
Very good
9,968 reviews

Food

7.1

Boarding

8.2

Crew

8.5

Entertainment

7.1

Comfort

7.9

Overall

8.0

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
4,294 reviews
Alaska Airlines
8.0
Very good
9,968 reviews

Food

7.1

Boarding

8.2

Crew

8.5

Entertainment

7.1

Comfort

7.9

Overall

8.0

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
7,934 reviews
Alaska Airlines
8.0
Very good
9,968 reviews

Food

7.1

Boarding

8.2

Crew

8.5

Entertainment

7.1

Comfort

7.9

Overall

8.0

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
8,696 reviews
Alaska Airlines
8.0
Very good
9,968 reviews

Food

7.1

Boarding

8.2

Crew

8.5

Entertainment

7.1

Comfort

7.9

Overall

8.0

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
9,968 reviews

Food

7.1

Boarding

8.2

Crew

8.5

Entertainment

7.1

Comfort

7.9

Overall

8.0

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 Louisville to Ontario. 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 Louisville to Ontario round-trip?

    Delta, at $307, was found to be the cheapest airline from Louisville to Ontario.Alternate airlines to your destination round-trip include United Airlines and Southwest. Delta is currently priced 44% below the average price you’ll pay for this route.

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

    $172 is the cheapest one-way deal found within the past few days, from Delta. You may also be able to find cheap deals on American Airlines and United Airlines, with prices starting from $199 and $204, respectively.

  • 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, August is the cheapest month in which you can book a flight from Louisville to Ontario (average of $246). Flying from Louisville to Ontario in March is currently the most expensive (average of $328). 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 4 airlines flying from Louisville to Ontario

Discover the top 4 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 May 1, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$257Average$506FlexibilityNo cancel feeOn-time69%
DeltaCheapest$288Average$416FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$306Average$486FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$364Average$506FlexibilityNo cancel feeOn-time63%

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