ONT - SDF

$172 Find Cheap Flights from Ontario to Louisville

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Ontario to Louisville departing on 8/4. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy

KAYAK searches hundreds of travel sites at once for deals on flights to Louisville

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ontario to Louisville, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ontario to Louisville, as well as popular online travel agencies
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Flights Deals

Cheap Flights from Ontario to Louisville (ONT-SDF)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Ontario to Louisville that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Ontario to Louisville

Thu, Oct 2 - Mon, Oct 6
American Airlines Logo
12:45 pm - 11:34 pmONT-SDF
7h 49m1 stop
American Airlines Logo
6:17 pm - 12:15 amSDF-ONT
8h 58m1 stop
$343American Airlines
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Thu, Oct 2 - Mon, Oct 6
American Airlines Logo
7:16 pm - 9:24 amONT-SDF
11h 08m2 stops
American Airlines Logo
3:46 pm - 8:04 pmSDF-ONT
7h 18m1 stop
$348American Airlines
Find Deal
Thu, Aug 21 - Sun, Aug 24
Southwest Logo
5:20 am - 3:30 pmONT-SDF
7h 10m1 stop
Southwest Logo
6:20 am - 9:35 amSDF-ONT
6h 15m1 stop
$366Southwest
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Thu, Aug 21 - Sun, Aug 24
Southwest Logo
12:55 pm - 11:40 pmONT-SDF
7h 45m2 stops
Southwest Logo
6:20 am - 9:35 amSDF-ONT
6h 15m1 stop
$371Southwest
Find Deal
Fri, Aug 22 - Sun, Aug 24
United Airlines Logo
5:10 am - 2:34 pmONT-SDF
6h 24m1 stop
United Airlines Logo
3:30 pm - 8:43 pmSDF-ONT
8h 13m1 stop
$384United Airlines
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Tue, Sep 16 - Tue, Sep 23
United Airlines Logo
5:10 am - 2:28 pmONT-SDF
6h 18m1 stop
United Airlines Logo
9:31 am - 12:32 pmSDF-ONT
6h 01m1 stop
$428United Airlines
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Sun, Jul 27 - Mon, Aug 4
Delta Logo
11:40 am - 12:32 amONT-SDF
9h 52m1 stop
Delta Logo
5:53 pm - 10:27 pmSDF-ONT
7h 34m1 stop
$430Delta
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Sun, Jul 27 - Wed, Jul 30
Delta Logo
10:05 pm - 8:50 amONT-SDF
7h 45m1 stop
Delta Logo
5:53 pm - 10:27 pmSDF-ONT
7h 34m1 stop
$432Delta
Find Deal
Tue, Sep 16 - Tue, Sep 23
Alaska Airlines Logo
7:10 am - 11:40 pmONT-SDF
13h 30m2 stops
Alaska Airlines Logo
10:00 am - 6:36 pmSDF-ONT
11h 36m2 stops
$447Alaska Airlines
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Fri, Aug 22 - Mon, Aug 25
Alaska Airlines Logo
7:10 am - 10:52 pmONT-SDF
12h 42m2 stops
Alaska Airlines Logo
12:15 pm - 11:53 pmSDF-ONT
14h 38m2 stops
$517Alaska Airlines
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KAYAK's insights & trends for Ontario to Louisville flights

Get data-powered insights and trends into flights from Ontario to Louisville to help you find the cheapest flights, the best time to fly and much more.

What’s the cheapest day of the week to fly from Ontario to Louisville?

The average price of all round-trip flights from Ontario to Louisville clicked on KAYAK for each day over the last 12 months.

When flying from Ontario to Louisville, you should consider leaving on a Saturday and avoid Mondays if you are looking for the best rates. For your return to Ontario, you’ll find the best rates on Thursdays and the most expensive ones on Tuesdays.

What is the cheapest month to fly from Ontario to Louisville?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Ontario to Louisville, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Ontario to Louisville is August, where tickets cost $354 (return) on average. On the other hand, the most expensive months are March and December, where the average cost of round-trip tickets is $556 and $556 respectively.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Ontario to Louisville, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from Ontario to Louisville, you should book around 3 weeks before departure. For the absolute cheapest price, our data suggests you should book 20 weeks before departure.

Good to know

Low seasonFebruary
High seasonSeptember
Cheapest flight$172
Best time to beat the crowds with an average 22% drop in price.
Most popular time to fly and prices are also 2% lower on average.
Flight from Ontario to Louisville

When to book flights from Ontario to Louisville

Are your dates flexible? Find out the best times to travel from Ontario to Louisville based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from Ontario to Louisville

  • What is the cheapest flight from Ontario to Louisville?

    In the last 3 days, the lowest price for a flight from Ontario to Louisville was $172 for a one-way ticket and $343 for a round-trip.

  • Do I need a passport to fly between Ontario and Louisville?

    A passport is not required to fly from Ontario to Louisville.

  • Which aircraft models fly most regularly from Ontario to Louisville?

    We unfortunately don’t have that data for this specific route.

  • Which airline alliances offer flights from Ontario to Louisville?

    oneworld, SkyTeam, and Star Alliance are the airline alliances operating flights between Ontario and Louisville, with oneworld being the most commonly used for this route.

  • Which is the best airline for flights from Ontario to Louisville, Southwest or Delta?

    The two airlines most popular with KAYAK users for flights from Ontario to Louisville are Southwest and Delta. With an average price for the route of $472 and an overall rating of 8.0, Southwest is the most popular choice. Delta is also a great choice for the route, with an average price of $416 and an overall rating of 8.0.

  • How does KAYAK find such low prices on flights from Ontario to Louisville?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Ontario to Louisville.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Ontario to Louisville?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Louisville from Ontario is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Ontario to Louisville?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Louisville with an airline and back to Ontario with another airline. Booking your flights between Ontario and SDF can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Ontario to Louisville?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Louisville from Ontario up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top 4 airlines serving from Ontario to Louisville

 
See real verified KAYAK customer reviews for airlines flying from Ontario to Louisville. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Ontario to Louisville? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
8.0
SouthwestOverall score based on 4272 reviews
8.2Boarding
7.0Food
8.6Crew
7.6Entertainment
8.0Comfort
Airline reviews

Delayed flight. Nicest crew member was a SW pilot flying seated next to me who kindly move to seat the final passenger. Flight extra delayed. My cup of refreshment of ginger ale was so packed with ice it was literally 2 sips.

4.0 OkayTraci, Jun 2025OAK - SEA
Read more Southwest reviews

Delayed flight. Nicest crew member was a SW pilot flying seated next to me who kindly move to seat the final passenger. Flight extra delayed. My cup of refreshment of ginger ale was so packed with ice it was literally 2 sips.

No trays in our seats, we sat in first row, purchased a business class fare. Had to hold our drinks and snack in our hands. No plugs for our cell phones. Had to pay for it a drink cocktail each. Seats so uncomfortable.

Flight wasn’t even full, but too many carry-ons caused us to run out of bin space. New bag fee has folks who would usually check their bags carrying on. Watching Southwest morph into Spirit/Frontier is so sad to watch

Southwest is Southwest. No frills. If you're luck enough to get a happy crew (we did), then it makes for a nicer flight.

The seats were a bit cramped and worn, but otherwise okay.

It was a perfect flight in all aspects! Both legs!

Great flight, 47 passengers on a 180 seat plane. Stewardess was pleasant and cheerful.

I liked the crew member who gave flight instructions on "in case of a problem:. The seats are so small that only a young teenager could sit in middle seat.

Great flight staff. Ease of boarding. Overall, very uneventful and easy trip.

Employees were kind and funny, as always! Flight was late but no announcements were made for people with tight connections to help them transition quickly. No service due to turbulence.

Crew was excellent. Comfort seats not as nice as other kinds of planes.

It was a great flight and the stewards and stewardess were all kind and accommodating!! The seats were comfortable and entertainment screen excellent!

There are 4 flights in consecutive gates with about the same departure time. Two flights were boarding at the same time. One was delayed or boarding would be happening at the same time. I am not sure what Delta and LAX need to do to have a better layout at the end of Terminal 2

There was a security issue at the airport and we were unable to land. We circled endlessly and then landed at another airfield for fuel. We then circled the airport again, almost landed but didn’t fully touch down before circling again. I am thankful to the crew for keeping us safe- the issue was the airline and staff at the airport getting us seats on our connecting flights. That part was hours of searching for someone and getting in double my steps.

Most aspects were good however if they assign boarding zones they ought to enforce them or why bother? My luggage from SAN-JFK-MAD was lost in NY so I without my main bag for two days upon arrival in Spain. They were helpful in tracking it and eventually delivered it to my hotel. The flub was because of a delay upon arrival in NYC. I had booked 2 1/2 hours between flights but we had to hold on the taxiway for an hour after landing while waiting for a clear gate which likely caused the baggage error.

Excellent flight, the planes were newer, they did a nice job with boarding, great service overall.

It would be nice if was given wires ear buds. Overall was a good experience was able to sleep on the plane

737-800 in first class was pretty dumpy. Seat had an uncomfortable angle, storage under the seat was blocked so even my very modest backpack didn't fit, power outlet was flaky. Weird tiny seat pockets that couldn't hold a gallon ziploc bag, emesis bag missing, etc. etc. No in-flight service due to turbulence. Crew was excellent, boarding was smooth despite a full flight.

Delta flight was on time, seats were comfortable, and crew was nice.

Thank you for not flipping the plane on the run way. You guys get a 5 star rating for the flight!!!

Boarded plane and then delayed 1.5 hours while on the plane

Horrific. They missed my connecting flight to San Diego. I didn’t get there until Monday at 9am when I had a mandatory court settlement conference scheduled at 6am since we had parties on the east coast. This caused many issues. All because United apparently forgot to hold the doors open until my flight landed that only had a 10 minute delay. This was the last flight to Southern California. So I couldn’t even rent a car to finish the trip. United cannot be trusted when traveling on specific days and times since weather didn’t have anything to do with the delays.

Really good 😊 the woman at the gate entrance was a little rude checking in our carry-on but i dont think she worked for the airline, she worked for the airport at sacramento, other than that amazing.

it was so bad. I tried to board my flight from vancouver to saskatoon. And to my surprise they did not board me cause the flight was changed and no email was send to me. and on my boarding pass which i got from seattle says different flight. I did not knew anyone from Vancouver, air canada crew was rude, i asked for today flight but they were rude and i had early morning dental appointment in saskatoon. I was so much in pain and my whole day is wasted today. and i suffered alot. They did provide me hotel but they did not provide me any food. I am really really disappointed first time had so bad experience with air canada. I may think twice to book it again. If i can get any reply or any composition that would be great. Thanks

Very comfortable (upgraded to business class). The audio on my screen didn’t work, but I managed to play the audio through my phone while watching the screen.

I was supposed to be on business class at first class from Denver back to Miami due to weather changes. I missed my connection and it’s put on a flight to Fort Lauderdale. Instead of honoring my business class/1st class ticket, they put me in coach, but there were two first class seats open. I think it’s absolutely disgusting that I paid for first class $1300 ticket and they put me in economy and they had to open seats available and I have still not been refunded the difference. I ended up having to eat a snack box instead of the meal I was supposed to get and did not get home till 2 AM so I think that’s a little pathetic that I had to live off crackers for dinner And my poor dog ate some cheese and salami. Oh yes, apparently when they switched me to the new flight they forgot to mention I had a service dog

Boarding seemed to be organized bedlam. For what ever reason, preboarding took longer than 20 minutes. Made the plane 20 minutes late taking off. Luckily we arrived on time. Flight crew seemed very friendly. Only slight turbulence.

The personnel were professional and friendly. The Boeing 737 Max 9 is too claustrophobic and was very warm at both airport gates, and still warm in the air.

While the staff was pleasant and helpful, the following observations are for your awareness. There was some delay on the tarmac on take off and landing. The paid lunch/food offerings were limited. Entertainment was only available on WiFi at a cost.

get E+, a must for 5 hours flight if you are tall

Almost a 6 hour flight and the only food option is a cheese plate… and chips. Also how is it there are no options for texting on American. I’ll be going back to delta and united.

The chair cushions may need an upgrade. I have been noticing they are so worn out, thin so you’d sit in a dip 😄. Other than that, all was an enjoyable trip. Thanks AA!

Cramped seats. FAA should make airlines have more legroom, for even short people complain

Eventless. It was a good flight and good crew. Can’t complaint.

Very helpful ground crew after an earlier flight delay and being rebooked on a different flight.

The plane was late and then sat on the runway for almost 45 minutes before taking off.

Everything was fine. Flight boarded and departed on time. Seating was spacious enough for my carryon to fit under the seat in front of me. No complaints at all. Flight even arrived early.

We kept being told that the flight was full and that all overhead compartments were full and therefore had to check in our hand luggage. We were some of the last people to board and noticed that there was still sufficient space in the overhead compartments. We were obliged to check in hand luggage when there was space and so had to wait at luggage retrieval which took a while to then noticed damage to our luggage - not a great experience!

This was an overnight flight. There was no meal service in first class, just a simple snack basket was offered along with beverages. There should have been some type of continental breakfast prior to arrival in PHL. As an Executive Platinum American Airlines Advantage member, I received no name recognition from the first class flight attendant. When disembarking at PHL, the flight attendants were more interested in their cell phones than saying "thank you" to the passengers as they disembarked.

The flight was quick and to the point. The crew just did their job w/o excessive talking and everything was just perfect.

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