ONT - MKE

$125 Find Cheap Flights from Ontario to Milwaukee

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 Milwaukee 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 Milwaukee

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ontario to Milwaukee, 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 Milwaukee, 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
$283
Overall average: $459
Alaska Airlines
Tue 4/21Tue 4/28
ONT - MKE • 1 stop
Cheapest one-way
$125
Typical prices: $183-$349
Frontier
Mon 3/30
ONT - MKE • 1 stop
Top airlines
Alaska Airlines
Cheapest • from $283 (round-trip)
Southwest
Best reviews • 8.0 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
Nonstop flights
Not available
There are currently no direct flights between Ontario and Milwaukee. You'll need at least 1 connection.
Insights
Insights
Insights
Insights
Top layover airports
Dallas (DFW)
Cheapest • Avg $364 (round-trip)
Las Vegas (LAS)
Shortest trip • 5h 46m (one-way)
Insights
Insights
Insights
Insights
When to travel
September
Cheapest • 14% price drop
June
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
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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 Milwaukee!
Flight Deals
Booking Insights
Flight Deals

Cheap Flights from Ontario to Milwaukee (ONT-MKE)

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

Tue, Apr 21 - Tue, Apr 28
Alaska Airlines Logo
6:00 am - 2:13 pm
ONT
-
MKE
30h 13m
1 stop
Alaska Airlines Logo
7:00 am - 9:45 am
MKE
-
ONT
28h 45m
1 stop
$283Alaska Airlines
Sun, Apr 26 - Thu, May 7
Multiple Airlines Logo
12:59 am - 4:10 pm
ONT
-
MKE
13h 11m
1 stop
Multiple Airlines Logo
3:09 pm - 11:59 pm
MKE
-
ONT
10h 50m
1 stop
$340Multiple Airlines
Fri, May 1 - Mon, May 4
Alaska Airlines Logo
7:59 pm - 2:43 pm
ONT
-
MKE
16h 44m
1 stop
Alaska Airlines Logo
3:09 pm - 2:32 pm
MKE
-
ONT
25h 23m
1 stop
$353Alaska Airlines
Wed, Mar 25 - Tue, Mar 31
Alaska Airlines Logo
7:08 pm - 2:14 pm
ONT
-
MKE
17h 06m
1 stop
Alaska Airlines Logo
3:10 pm - 9:39 am
MKE
-
ONT
20h 29m
1 stop
$373Alaska Airlines
Wed, Apr 1 - Tue, Apr 14
Delta Logo
1:20 pm - 9:15 pm
ONT
-
MKE
5h 55m
1 stop
Delta Logo
5:30 am - 11:36 am
MKE
-
ONT
8h 06m
1 stop
$388Delta
Fri, Mar 27 - Tue, Mar 31
Frontier Logo
6:15 am - 6:51 pm
ONT
-
MKE
10h 36m
1 stop
Frontier Logo
1:57 pm - 3:57 pm
MKE
-
ONT
28h 00m
1 stop
$396Frontier
Fri, Apr 10 - Sat, Apr 11
Delta Logo
1:20 pm - 9:15 pm
ONT
-
MKE
5h 55m
1 stop
Delta Logo
7:35 am - 12:23 pm
MKE
-
ONT
6h 48m
1 stop
$397Delta
Thu, Apr 23 - Sun, Apr 26
Alaska Airlines Logo
7:59 pm - 2:13 pm
ONT
-
MKE
16h 14m
1 stop
Alaska Airlines Logo
7:00 am - 9:45 am
MKE
-
ONT
28h 45m
1 stop
$403Alaska Airlines
Thu, Apr 16 - Sun, Apr 19
Southwest Logo
1:55 pm - 10:00 pm
ONT
-
MKE
6h 05m
1 stop
Southwest Logo
8:15 pm - 12:05 am
MKE
-
ONT
5h 50m
1 stop
$408Southwest
Wed, Apr 1 - Tue, Apr 7
United Airlines Logo
5:10 am - 2:27 pm
ONT
-
MKE
7h 17m
1 stop
United Airlines Logo
8:15 am - 6:02 pm
MKE
-
ONT
11h 47m
2 stops
$412United Airlines
Booking Insights

KAYAK's insights & trends for Ontario to Milwaukee flights

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

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Ontario to Milwaukee, 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 Milwaukee is September, where tickets cost $366 (return) on average. On the other hand, the most expensive months are January and April, where the average cost of round-trip tickets is $557 and $459 respectively.

Good to know

Low seasonFebruary
Cheapest flight$125
Flight from Ontario to Milwaukee

When to book flights from Ontario to Milwaukee

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

  • What is the cheapest flight from Ontario to Milwaukee?

    In the last 3 days, the lowest price for a flight from Ontario to Milwaukee was $125 for a one-way ticket and $283 for a round-trip.

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

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

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

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

  • Which airline alliances offer flights from Ontario to Milwaukee?

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

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

    The two airlines most popular with KAYAK users for flights from Ontario to Milwaukee are Southwest and Delta. With an average price for the route of $400 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 $442 and an overall rating of 7.9.

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

    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 Milwaukee.

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

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

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

    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 Milwaukee 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 Milwaukee

 
See real verified KAYAK customer reviews for airlines flying from Ontario to Milwaukee. 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 Milwaukee? 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 4302 reviews
8.0Comfort
7.5Entertainment
8.1Boarding
7.0Food
8.6Crew
Airline reviews

Flight boarded late after announcing on time boarding. Flight arrived only a little late despite late departure. Had trouble connecting to WiFi

4.0 OkayEmma, Mar 2026
LAX - PHX
Read more Southwest reviews

Flight boarded late after announcing on time boarding. Flight arrived only a little late despite late departure. Had trouble connecting to WiFi

The Southwest experience has definitely taken a dive from its early days. You can no longer deferentiate from other airlines. Air travel is too expensive. Southwest is no longer budget friendly. They have lost me as a loyal customer.

The charges were ridiculous for an hour flight and the turbulence was very scary.

The seats are now more narrow. I paid for front row the seats in the front are even more narrow than before.

The wifi on the plane is great. The only issue that I have is that I prefer an aisle seat and on my trips this week, I was either in the middle or window. If we can work to secure aisle seating, I will be thrilled. Nice trip.

Great flight but super high price. Glad it was a business trip and not personal

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

We got exit row seats both flights. Everything was running on time

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.

Flight was delayed by 3-hours and their fix was… complimentary pretzels.

The crew, and fellow passengers, were super gracious and kind. There seemed to be plenty of bin space even though the plane was full. It’s nice to get a glass of wine with dinner in Premiere seating, and there was a lot of food.

Everything I mentioned earlier - the airbus was more comfortable indeed and the experience was further enhanced.

The plane was an older model, so it wasn’t as comfortable as others. The flight attendants were not helpful during onboarding. It was a full flight so there was chaos finding space for baggage.

Awesome! On time flight, early arrival, and a complimentary upgrade!

Delta One is extraordinary. I fly business when somebody hires me. I just wonder why there is such a chasm between business class and the insanely inhumane and nonsensical coach. The seats are not large enough to fit even my tiny wife. We fly 10% of what we did because we don’t want to pay 5-10 k but for $400 it’s unbearable. It seems like the accountants took over and made stupid decisions. Screw in 20 extra seats and make it so unbearable that people fly 90% less. Just put the damn price up and put some proper chairs in. But business, yay.

Delta’s staff is unmatched. From the gate agents, to the pilots, to the flight attendants… all top of the industry.

The flight was delayed for about 2 hrs. Other than it, it was good.

I am extremely disappointed that delta internal pilot manuals now refer to the Gulf of Mexico as the “gulf of America”. You can bow down to the Orange turd on your own. I will never fly delta again

My flight was cancelled with no explanation after I had already cleared security. I was given 4 options to rebook, only one being non-stop like I had paid for. I grabbed it. It was 4 plus hours later and then took off even later. Biggest complaint is that I booked early and had an aisle seat. They gave me a "window" seat in front of the exit row, so the seat did not decline. I weigh all of 103 #s and it was tight for me! For what I paid, I feel I was kind of ripped off. I think they should have given me the empty comfort seat for the inconvenience. There was no apology nor any explanation as to why the flight was cancelled. My guess is it benefitted Delta in some way.

Staff were good. My seat was in need of repair, but for a short flight was not problematic. Usual basic snack and drink setup that you'll find on any US carrier. Over, a decent, basic flight.

Complimentary light meal would be appreciated. But great flight crew service on all legs

Flight delayed for more than 16 hrs and no effort was spent to provide an alternate

Women boarding passengers at the gate was absolutely rude and disrespectful of passengers. The flight attendant was absolutely delightful! Smiling and connected with the passengers. So happy. The seats are cramped and uncomfortable but I guess that’s just the way it is Communication regarding flight was excellent

it was a very short flight so my expectations were low.

Very disappointing given gate agent behavior. Filed a formal complaint with United.

Crew was great (professional, attentive, prompt). Snacks for 4 hrs flight is deplorable.

Flight delayed. WiFi connectivity very poor if not existant. Last minute arrival forced me to run to catch my connection.

Terrible. No customer service, no food, no drinks on a 6 hour premier economy booking.

It was a pretty standard flight... until the almost hour and a half spent on the taxi way. I get that the weather has been poor but the delay had nothing to do with the weather and more to do with a plane with several issues tying up the gate. I get that that happens from time to time but this has been EVERY flight I've been on for the past 5 years and I fly 3 to 5 times a year. This isn't just United... it's American, it's Delta. It's an issue with the entire industry. I work for UPS and packages on a cargo plane get better service than people do these days. Anymore I HATE flying.

My seat was assigned last row behind restrooms No legroom’s I’m very Pettit Still was not comfortable Food choice was excellent

The chicken wrap was tiny ($13 for what looked like a 1/3 of a normal wrap?) and disgusting.

Mediocre would be best description. Food bland. Seat biz class uncomfortable to sleep. Crew never dimmed lights completely in an overnight flight to Europe. Would avoid AA if possible.

Small plane, poor meal choices for first class, bad terminal and boarding experience at LAX

Massimo, flight attendant was very authentic, attentive - wonderful. Food/wrap was just okay.

Never ontime and always delays. Long waits for customer service and often app doesn’t work

Experience was great. The best part is the free Wi-Fi connection which helps me to work on the flight

The flight was fine. It's the satellite terminal that supports American eagle flights is what sucks. There is only one food option and everything there is way overpriced. I mean I know it's airport pricing, but it's even crazier than that. I bought a sandwich in a plastic container for $18.

The flight was really crowded. Flight attendants were just ok.

Flight was delayed for 2 hours, then last minute the change to on time. The satélite location is far and a nightmare to get to.

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

Information on your arrival and departure airports