MKE - ONT

$140 Find Cheap Flights from Milwaukee to Ontario

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Milwaukee to Ontario departing on 3/30. 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, 0 bags

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

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Milwaukee to Ontario, 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 Milwaukee to Ontario, as well as popular online travel agencies
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41,299,237 searches in the past 7 days on KAYAK

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Everything you should know

Cheapest round-trip
$310
Overall average: $466
Frontier
Mon 3/16Fri 3/20
MKE - ONT • 1 stop
Cheapest one-way
$140
Typical prices: $155-$248
Frontier
Mon 3/30
MKE - ONT • 1 stop
When to travel
January
Cheapest • 31% price drop
December
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
Start a new search
KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to Ontario!
Flight Deals
Booking Insights
Flight Deals

Cheap Flights from Milwaukee to Ontario (MKE-ONT)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Milwaukee to Ontario 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 Milwaukee to Ontario

Mon, Mar 16 - Fri, Mar 20
Frontier Logo
7:15 pm - 11:59 pm
MKE
-
ONT
6h 44m
1 stop
Frontier Logo
6:15 am - 6:51 pm
ONT
-
MKE
10h 36m
1 stop
$310Frontier
Wed, Feb 25 - Mon, Mar 2
Delta Logo
5:23 am - 12:02 pm
MKE
-
ONT
8h 39m
1 stop
Delta Logo
10:20 pm - 9:09 am
ONT
-
MKE
8h 49m
1 stop
$315Delta
Sat, Feb 21 - Tue, Feb 24
United Airlines Logo
4:10 pm - 8:50 pm
MKE
-
ONT
6h 40m
1 stop
United Airlines Logo
8:00 am - 9:44 pm
ONT
-
MKE
11h 44m
2 stops
$320United Airlines
Sat, Feb 7 - Mon, Feb 16
Delta Logo
7:45 am - 12:16 pm
MKE
-
ONT
6h 31m
1 stop
Delta Logo
10:20 pm - 9:09 am
ONT
-
MKE
8h 49m
1 stop
$326Delta
Fri, Mar 20 - Mon, Mar 23
Frontier Logo
7:46 pm - 11:59 pm
MKE
-
ONT
6h 13m
1 stop
Frontier Logo
6:15 am - 6:20 pm
ONT
-
MKE
10h 05m
1 stop
$330Frontier
Tue, Feb 10 - Sat, Feb 14
United Airlines Logo
2:32 pm - 10:53 pm
MKE
-
ONT
10h 21m
2 stops
United Airlines Logo
5:00 am - 2:56 pm
ONT
-
MKE
7h 56m
1 stop
$331United Airlines
Wed, Mar 18 - Fri, Mar 20
Alaska Airlines Logo
3:10 pm - 11:59 pm
MKE
-
ONT
10h 49m
1 stop
Alaska Airlines Logo
7:08 pm - 2:14 pm
ONT
-
MKE
17h 06m
1 stop
$333Alaska Airlines
Sun, Mar 15 - Fri, Mar 20
Alaska Airlines Logo
3:47 pm - 11:08 am
MKE
-
ONT
21h 21m
1 stop
Alaska Airlines Logo
7:08 pm - 2:14 pm
ONT
-
MKE
17h 06m
1 stop
$335Alaska Airlines
Wed, Feb 4 - Tue, Feb 10
Delta Logo
5:30 am - 11:31 am
MKE
-
ONT
8h 01m
1 stop
Delta Logo
1:11 pm - 9:15 pm
ONT
-
MKE
6h 04m
1 stop
$337Delta
Thu, Feb 5 - Sun, Feb 15
Delta Logo
5:30 am - 11:31 am
MKE
-
ONT
8h 01m
1 stop
Delta Logo
10:20 pm - 9:09 am
ONT
-
MKE
8h 49m
1 stop
$343Delta
Booking Insights

KAYAK's insights & trends for Milwaukee to Ontario flights

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

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Milwaukee to Ontario, 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 Milwaukee to Ontario is January, where tickets cost $303 (return) on average. On the other hand, the most expensive months are February and October, where the average cost of round-trip tickets is $556 and $550 respectively.

Good to know

Low seasonJanuary
Cheapest flight$140
Best time to beat the crowds with an average 31% drop in price.
Most popular time to fly and prices are also 2% lower on average.
Flight from Milwaukee to Ontario

When to book flights from Milwaukee to Ontario

Are your dates flexible? Find out the best times to travel from Milwaukee to Ontario 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 Milwaukee to Ontario

  • What is the cheapest flight from Milwaukee to Ontario?

    In the last 3 days, the lowest price for a flight from Milwaukee to Ontario was $140 for a one-way ticket and $310 for a round-trip.

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

    No

  • Which airports will I be using when flying from Milwaukee to Ontario?

    Milwaukee airport is called Milwaukee-Mitchell and the only airport in Ontario is Ontario.

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

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

  • Which airline alliances offer flights from Milwaukee to Ontario?

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

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

    The two airlines most popular with KAYAK users for flights from Milwaukee to Ontario are Southwest and Delta. With an average price for the route of $430 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 $444 and an overall rating of 7.9.

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

    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 Milwaukee to Ontario.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Ontario from Milwaukee 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 Milwaukee to Ontario?

    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 Ontario with an airline and back to Milwaukee with another airline. Booking your flights between Milwaukee and ONT 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 Milwaukee to Ontario?

    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 Ontario from Milwaukee 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 Milwaukee to Ontario

 
See real verified KAYAK customer reviews for airlines flying from Milwaukee to Ontario. 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 Milwaukee to Ontario? 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 4261 reviews
7.5Entertainment
7.0Food
8.1Boarding
8.0Comfort
8.6Crew
Airline reviews

3 hour delay. Had to change plans and was still delayed.

2.0 MediocreAnonymous, Jan 2026
SFO - SAN
Read more Southwest reviews

3 hour delay. Had to change plans and was still delayed.

The flight crew was extremely rude and especially not helpful when our flight was delayed.

The boarding and seat assignment system no longer works for me, but I know it is being replaced. Otherwise, I am good with the overall experience.

The lead steward kept singing about "San Francisco" and hotel California---more annoying than humorous....needs work. Flight was smooth and on time.

Still a fan of open seating. Flight was on schedule and arrived on time. The 737 MAX is very comfortable.

San Diego airport is brand new, spacious, airy and very smooth checkin at SW baggage drop.

Ever since Southwest starting charging for bags, passengers don't want to pay to check their bags, so the gate agents have to beg people to check their roller bags now because there's "not enough space". This was a terrible business move by Southwest.

Delays delays delays. Late taking off, late landing, wait for a gate, etc.

Connecting flight is on time and boarding was a breeze!

Very smooth checking in our luggage with a super pleasant SW agent. I enjoyed a fun entertaining movie.

I usually get upgraded so my experience is usually amazing. I did not get upgraded this time - which was fine - but the wifi had issues, the monitors were going in & out, & (though not Delta's fault) one of the gentlemen next to me desperately needed a shower.

I really liked the legroom. I am 6’4”.a at For some reason our seats were not together and using the app to fix it didn’t work. Passengers were nice enough to move for us but you should absolutely ensure a parent sits with their child.

Staff was exceptional! Everyone was kind, professional and friendly making the trip very pleasant. Thank you!

Staff were friendly and happy. Delta could make sure passengers that don't have the app know of changes. Without Kayak I would not have known about the change of gate or the delay. Kayak was faster to notify me.

They changed planes and the new plane couldn’t carry enough fuel to fly across the country so we had to stop in Kansas City to refuel. Flight was delayed .

Flight was too crowded and seats are too small, especially since passengrs are getting larger. Having a middle seat is ALWAYS tough! Woman on my left was large & kept creeping in to my space. Flight personnel were great! Have more savory rather than sweet snacks please.

The crew took good care of us. The flight from ATL to SFO is a longer one, and there were multiple beverage offerings. I like the 757's that Delta uses. Good airplane that is comfortable. I do wish Delta would separate Priority boarding from the better seats. I would gladly take a smaller seat in an open row than be jammed into Comfort just to get priority boarding, just to make sure I don't have to check a bag.

Gate agent rushed to fill hot jetway with crowd so it took over 12 minutes to go from gate to plane. Just like a discount airline Pooly prepared cabin and third time that claim of rough air prevented any cabin service. Friends on a Southwest flight at similar time had service.

I was uncomfortably cold on the plane. Other than that it was uneventful and therefore as enjoyable as a plane ride can be.

Food was surprisingly good but the WiFi was not great

Yet another flight in which beverage and snack service was skipped. Other that that, firmly mediocre. Landed early, to gate late due to congestion at the gates. Airline's fault or airports fault: unknown.

Teeny tiny bathrooms, crew was not realistic about when we'd arrive.

The flight was delayed by two de-icings. The seatbelt did not work correctly. It did not stay tight.

Unbelievably poor service from flight attendants. They didn’t even do water service on a four hour flight. Just disrespectful.

Flight was late - I was downgraded from first class to coach

United needs to step up their game. Delayed flight leaving Seattle, San Francisco. Older aircraft, not very comfortable.

Plane boarded early a quickly, was mostly full. We left close to on time. And landed early.

7 hours delayed due to operational issues on United’s end. Basically laziness.

Flight was timely, relatively comfortable, with decent entertainment and food served. Only problem encountered was with the free messaging which I highly appreciate, but it did not work from iphone to non-iphones.

The internet service I paid for didn’t work at all and the flight crew was not very friendly.

Amazing I love American. I’ll never fly anyone else if I can help it.

Everything about the flight was lovely. My only suggestion would be to offer a few more options of tv series from Apple TV or HBO.

After the door had been closed, the cockpit makes an announcement that catering is running late and it is not the airline's fault. It is their fault in the sense that we had to sit for 2 hours or more when we could have stayed in the terminal. Poor communications between catering and airline. This caused a young man to lose his temper and he went storming out hitting objects. He had complained to the gate agent that he had already waited at the gate 7 hours and when can the airplane leave? Airilnes do a poor job of explaining delays, maintenance issues, etc. whereas being truthful may gain more sympathy or understanding.

I bought wifi and most of the flight could not even use it my apps would just spin. I couldn't even listen to music. super frustrating.

We were told the flight was delayed 5 times, then it was moved to the next day.

The experience with American Airlines was good, although the Philippines Airlines flight was much better (better seats, better food, better entertainment options, overall better). Again, the MIA to LAX flight was fine, but nothing in comparison to the comfort and accommodations of the Philippines Airlines flight from LAX to MNL.

Loved the crew . Absolutely no complaints. Except for luggage lost

Wish some foods provided rather than just biscuit/cookie for flight more than 2 hours

We are too tired and frustrated to comment politely at this point

The flight crew was rude. We were in first class and no one even offered water until an hour after we were in the air. Horrible experience

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

Information on your arrival and departure airports