ONT - SDF

$140 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 10/29. 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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Flight 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 23 - Mon, Oct 27
Multiple Airlines Logo
6:05 am - 2:02 pmONT-SDF
28h 57m1 stop
Multiple Airlines Logo
2:57 pm - 10:05 pmSDF-ONT
10h 08m1 stop
$244Multiple Airlines
Find Deal
Thu, Oct 23 - Mon, Oct 27
Multiple Airlines Logo
8:34 am - 7:15 pmONT-SDF
31h 41m2 stops
Multiple Airlines Logo
2:57 pm - 10:05 pmSDF-ONT
10h 08m1 stop
$261Multiple Airlines
Find Deal
Wed, Oct 22 - Mon, Oct 27
American Airlines Logo
10:09 am - 11:24 pmONT-SDF
10h 15m2 stops
American Airlines Logo
6:17 pm - 11:59 pmSDF-ONT
8h 42m1 stop
$323American Airlines
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Thu, Oct 30 - Thu, Nov 6
Southwest Logo
6:35 am - 4:35 pmONT-SDF
7h 00m1 stop
Southwest Logo
5:30 pm - 12:05 amSDF-ONT
9h 35m1 stop
$324Southwest
Find Deal
Sat, Feb 21 - Thu, Feb 26
American Airlines Logo
6:47 am - 5:25 pmONT-SDF
7h 38m1 stop
American Airlines Logo
8:19 pm - 11:43 pmSDF-ONT
6h 24m1 stop
$328American Airlines
Find Deal
Fri, Oct 24 - Wed, Oct 29
Delta Logo
10:00 pm - 9:56 amONT-SDF
8h 56m1 stop
Delta Logo
6:00 am - 10:26 amSDF-ONT
7h 26m1 stop
$337Delta
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Mon, Nov 3 - Sat, Nov 8
Southwest Logo
3:10 pm - 11:45 pmONT-SDF
5h 35m1 stop
Southwest Logo
7:10 am - 10:45 amSDF-ONT
6h 35m1 stop
$338Southwest
Find Deal
Mon, Nov 3 - Sat, Nov 8
Delta Logo
10:00 pm - 9:56 amONT-SDF
8h 56m1 stop
Delta Logo
3:00 pm - 9:20 pmSDF-ONT
9h 20m2 stops
$343Delta
Find Deal
Wed, Oct 22 - Wed, Oct 29
United Airlines Logo
6:36 pm - 10:01 amONT-SDF
12h 25m2 stops
United Airlines Logo
9:00 am - 5:34 pmSDF-ONT
11h 34m2 stops
$379United Airlines
Find Deal
Tue, Nov 4 - Sat, Nov 8
United Airlines Logo
1:33 pm - 10:29 pmONT-SDF
5h 56m1 stop
United Airlines Logo
8:00 am - 12:30 pmSDF-ONT
7h 30m1 stop
$410United Airlines
Find Deal

Everything you should know

Top airlines
American Airlines
Cheapest • from $323 (round-trip)
Southwest
Best reviews • 8.0 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
When to travel
February
Cheapest • 22% price drop
September
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
Cheapest round-trip
$244
Overall average: $536
Multiple Airlines
Thu 10/23Mon 10/27
ONT - SDF • 1 stop
Cheapest one-way
$140
Typical prices: $158-204
Delta
Wed 10/29
ONT - SDF • 1 stop
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KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to Louisville!
Booking Insights

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 February, where tickets cost $371 (return) on average. On the other hand, the most expensive months are March and October, where the average cost of round-trip tickets is $547 and $536 respectively.

Good to know

Low seasonFebruary
Cheapest flight$140
Best time to beat the crowds with an average 23% drop in price.
Most popular time to fly with an average 11% increase in price.
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 $140 for a one-way ticket and $244 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?

    Star Alliance, SkyTeam, and oneworld are the airline alliances operating flights between Ontario and Louisville, with Star Alliance 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 $473 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 $466 and an overall rating of 7.9.

  • 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 4248 reviews
7.0Food
8.6Crew
8.0Comfort
8.1Boarding
7.5Entertainment
Airline reviews

As always, the entire Southwest experience was wonderful, from online booking to flight to baggage retrieval. Very grateful.

10.0 ExcellentRobert, Sep 2025SFO - LAS
Read more Southwest reviews

As always, the entire Southwest experience was wonderful, from online booking to flight to baggage retrieval. Very grateful.

The weather could have been better. There was a 40 minute ATC delay in SFO because of marine fog and a micro cell storm delayed landing and take-off at Nashville. The gate was changed 5 minutes from boarding from gate B3 to gate C23 at Nashville airport.

The cabin was quiet for the redeye flight. The area was clean. The staff was great. The 787 Max was in good condition. Drawbacks were that the seat widths were tight for some passengers. The seat padding was at best average and for a long flight uncomfortable.

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.

Flight delayed for two and half hours and then canceled altogether due to mechanical issues. No mechanic onsite to fix so had to send one from LAX.

My husband upgraded our seats and I don't know if it was due to the type of planet was or if they didn't upgrade our seats. We were supposed to be in I believe comfort seats and they were just as tight as any other seat- no leg room and we are very tall people but at least it wasn't extremely cold. My husband did put in a complaint about our seating because he paid extra and if we would have known that the space and the tightness would have been the same, we just would have gotten the emergency row emergency row seats that we normally get. We love Delta but both our flights coming home we're not good. Oh I forgot to mention that on our flight to Hawaii our luggage wheels got broke and we had to purse new luggage on vacation then we never had this problem so we didn't know protocol and reported it after we got home only for them to tell is we only had 24hrs to report the damage. Not sure what was going on with Delta this vacation trip.

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.

I was in first class. The outlets at my seat did not work. The plane was shabby and run down. I had prepurchsed a day subscription for internet that was not redeemable. I had to repurchase the internet for my flight and then it didn’t work anyway. Quite disappointed in what was supposed to be the launch of a great vacation.

I understand stuff happens, but plane failures are likely due to lack of maintenance. Additionally, air conditioning wasn't working, no snack/drink service, no WiFi. Fortunately, the crew was communicative and light-hearted. United grabbed another plane and we were able to get to our destination.

Stuck on tarmac for two hours plus a 5.5 hour flight. Rude flight attendant. And no meals, not even for purchase!

I learned that seating towards the end of plane that a line forms for the restroom and people use your chair as a hand railing, bumping your seat consistently. I was seated in the aisle. I think that next time if I am towards the back row I would want to sit in the middle or window seat.

United sent me a mileage plus number last year but that number is invalid so I can’t use it to check into flights or collect mileage. There is human to speak about the problem, only computers who keep asking me if I am using the correct email. It’s so frustrating and I cannot resolve it.

Not a great experience. We paid for the upgrade for premium economy seats and seated ourselves in very comfortable seats. Someone came along with the same seat on their boarding pass. The aircraft had been changed and as a result we were booted out and sent further back to small uncomfortable seats. After complaining we were moved to emergency row seats, which gave us more leg room but the seats don’t recline. For people in our 70’s we found having to sit upright from California to NJ very uncomfortable. Not sure why they chose to move senior citizens instead of the two people that were allowed to take the more comfortable seats. Not happy.

Everything was great. Only thing that could’ve made it better was buy on board options for hot food, but the snacks were decent. The flight attendants were great. I had no complaints. I was able to make it to my destination safely

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 a red eye flight, so no meals were provided, but it was fine with snacks. The seats felt cramped and almost too narrow.

Very crowded flight but what can you expect these days?? Crew was accommodating.

The seats in economy were appeared to be quite thin and lack sufficient cushioning to be comfortable. Perhaps it was my seating position but the plane seemed notably load.

The entertainment package was vast and the selections were very current. Keep updating it was great.

The seat was so hard my tailbone was aching The crew was kind of a b**** because I made a joke that I didn't care if they close the door I total c*** when she was trying to f****** act like she was mad at me because I said that The flight was bumpy. Sure you didnt have control over that.

My Internet did not work for Outlook email or basically anything. I paid for one hour of in-flight usage and it was terrible. I spent a lot of time on different sites and browsers with no luck and a lot of frustration. Other than that, the flight was on time, crew was nice, service was fine. Seat was OK even though I paid for the extra 6 inches. I cannot imagine how tight the seats in the back must be.

4 hours late, including over +1 hour waiting in plane to take off. Baggage left behind too.

While waiting to claim my checked luggage, I discovered the airline had lost it. After a long wait and inquiries, I discovered it was on another flight. Fortunately, the airline finally sent my luggage home.

Was not able to watch most shows on the entertainment site. They would not load

Our flight was 1.5 hours delayed. There was no weather for the inbound flight, so I don't understand why. This meant a VERY late arrival and only a quick nap before my morning flight.

Everything you need to know for your flight from Ontario to Louisville

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