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$169 Cheap Flights from Ontario Intl. Airport (ONT) to Milwaukee (MKE)

View $169 flight on Wed, Oct 28, 2026Opens in a new window

Popular airlines from Ontario Intl. Airport (ONT) to General Mitchell Intl. Airport (MKE)

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Cheap Flights from Ontario Intl. Airport to Milwaukee (ONT-MKE)

Prices were available within the past 7 days and start at $169 for one-way flights and $337 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

American Airlines
Sat, Oct 3 - Tue, Oct 6
ONT
Ontario
MKE
Milwaukee
$337 Roundtrip, found 1 day ago
$337
Roundtrip
found 1 day ago
Select American Airlines flight, departing Sat, Oct 3 from Ontario to Milwaukee, returning Tue, Oct 6, priced at $337 found 1 day ago
Delta
Tue, Jan 26 - Wed, Jan 27
ONT
Ontario
MKE
Milwaukee
$337 Roundtrip, found 1 day ago
$337
Roundtrip
found 1 day ago
Select Delta flight, departing Tue, Jan 26 from Ontario to Milwaukee, returning Wed, Jan 27, priced at $337 found 1 day ago
Alaska Airlines
Thu, Nov 12 - Wed, Nov 18
ONT
Ontario
MKE
Milwaukee
$355 Roundtrip, found 3 days ago
$355
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Thu, Nov 12 from Ontario to Milwaukee, returning Wed, Nov 18, priced at $355 found 3 days ago
Alaska Airlines
Thu, Nov 12 - Wed, Nov 18
ONT
Ontario
MKE
Milwaukee
$361 Roundtrip, found 3 days ago
$361
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Thu, Nov 12 from Ontario to Milwaukee, returning Wed, Nov 18, priced at $361 found 3 days ago
Bargain Flight
Mon, Nov 23 - Fri, Nov 27
ONT
Ontario
MKE
Milwaukee
$363 Roundtrip, found 3 days ago
$363
Roundtrip
found 3 days ago
Select Bargain Flight flight, departing Mon, Nov 23 from Ontario to Milwaukee, returning Fri, Nov 27, priced at $363 found 3 days ago
United
Tue, Oct 20 - Sat, Oct 24
ONT
Ontario
MKE
Milwaukee
$368 Roundtrip, found 2 days ago
$368
Roundtrip
found 2 days ago
Select United flight, departing Tue, Oct 20 from Ontario to Milwaukee, returning Sat, Oct 24, priced at $368 found 2 days ago
United
Sat, Nov 14 - Wed, Nov 18
ONT
Ontario
MKE
Milwaukee
$371 Roundtrip, found 6 days ago
$371
Roundtrip
found 6 days ago
Select United flight, departing Sat, Nov 14 from Ontario to Milwaukee, returning Wed, Nov 18, priced at $371 found 6 days ago
United
Tue, Oct 20 - Sat, Oct 24
ONT
Ontario
MKE
Milwaukee
$373 Roundtrip, found 2 days ago
$373
Roundtrip
found 2 days ago
Select United flight, departing Tue, Oct 20 from Ontario to Milwaukee, returning Sat, Oct 24, priced at $373 found 2 days ago
United
Wed, Oct 28 - Fri, Oct 30
ONT
Ontario
MKE
Milwaukee
$375 Roundtrip, found 3 days ago
$375
Roundtrip
found 3 days ago
Select United flight, departing Wed, Oct 28 from Ontario to Milwaukee, returning Fri, Oct 30, priced at $375 found 3 days ago
United
Thu, Dec 3 - Fri, Dec 4
ONT
Ontario
MKE
Milwaukee
$376 Roundtrip, found 2 days ago
$376
Roundtrip
found 2 days ago
Select United flight, departing Thu, Dec 3 from Ontario to Milwaukee, returning Fri, Dec 4, priced at $376 found 2 days ago

Alternative airports near Milwaukee

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to General Mitchell Intl. MKE. Cheapest and Closest option available. Average driving time to city center is 13 minutes. Flights from $712
MKE
General Mitchell Intl.
CheapestClosest
Average driving time to city center13 min
Flights from $712

Frequently asked questions

How much does a flight from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Milwaukee, WI (MKE-General Mitchell Intl.) cost?
You can find cheap one-way flights from $169 and cheap return flights from $337 Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Milwaukee, WI (MKE-General Mitchell Intl.) with Expedia. One-way flights generally range between $196 and $868, and roundtrip flights usually range from $353 to $1177. Flight prices vary based on the month and day of the week you want to travel, as well as the airline and how far in advance you book your ticket. Filter your search on Expedia by "Price (lowest to highest)" to see the cheapest fares first, and use the Price Tracking tool to receive alerts when Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Milwaukee, WI (MKE-General Mitchell Intl.) ticket fares go up or down.*Typical price ranges based on flights available on Expedia in the last year. Prices include multi-airline options.
What is the cheapest month to fly from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Milwaukee, WI (MKE-General Mitchell Intl.)?
February is the cheapest month to fly from Ontario, CA (ONT) to Milwaukee, WI (MKE), with average return fares around $394. This is about 12% lower than the average price, as February typically sees fewer travelers after the holiday season. Other cheap months to fly from ONT to MKE include August and September.*Averages based on flights available on Expedia in the last year.
Which airlines fly direct from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Milwaukee, WI (MKE-General Mitchell Intl.)?
Enter ONT to MKE and your travel dates, then apply the 'Nonstop' filter to see only direct flights.
What is the cheapest airline that flies from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Milwaukee, WI (MKE-General Mitchell Intl.)?
American Airlines is one of the cheapest airlines offering connecting flights from Ontario, CA (ONT) to Milwaukee, WI (MKE), with round-trip tickets starting from around $558 with a layover in Dallas/Fort Worth Intl. (DFW). Use Expedia's search tool to compare the prices and schedules of airlines that fly this route to find the best option for your plans and budget.*Prices based on flights available on Expedia in the last year.
How do I find cheap flights from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Milwaukee, WI (MKE-General Mitchell Intl.)?
To find a cheap flight from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Milwaukee, WI (MKE-General Mitchell Intl.), be flexible with your dates. Traveling outside of peak vacation months and booking a mid-week flight can help you save. Early morning and late night flights are often more affordable, too. Expedia allows you to compare flight times, airlines and routes all in one place to find low fares. You can also set up Price Tracking and receive alerts when fares go up or down.
What is the best time to fly from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Milwaukee, WI (MKE-General Mitchell Intl.)?
For flights from Ontario, CA (ONT) to Milwaukee, WI (MKE), the best months to fly are February and September. You can find return flights for about $394 during these months, which are the cheapest options. February offers lower prices, while September provides a pleasant travel experience with mild weather.*Prices based on flights available on Expedia in the last year.
What is the earliest flight from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Milwaukee, WI (MKE-General Mitchell Intl.)?
The earliest flight from Ontario, CA (ONT) to Milwaukee, WI (MKE) usually departs at around 12:05 AM, operated by Frontier Airlines. This is a seasonal service active in May. An early flight can help you make the most of your time in Milwaukee. To compare early flights on Expedia, select the "Early Morning" and "Morning" filters in your search.
What are the most popular departure times for flights from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Milwaukee, WI (MKE-General Mitchell Intl.)?
The most popular departure times for flights from Ontario, CA (ONT) to Milwaukee, WI (MKE) are in the early morning, from 6am to 9am. About 37% of passengers prefer this time window. Many major carriers, including American Airlines, Southwest Airlines, and United Airlines, offer flights during this window. This timing works well because it allows you to start your day early and arrive in Milwaukee with plenty of time to enjoy the day.
How long does it take to fly from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Milwaukee, WI (MKE-General Mitchell Intl.)?
Flying from ONT to MKE with a connection usually takes about 9 hours, traveling roughly 1,708 miles. Keep in mind that actual flight times can vary due to wind patterns, weather, and air traffic.
Can you fly business or first class from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Milwaukee, WI (MKE-General Mitchell Intl.)?
First class seats are offered on the ONT to MKE route. First class cabins are available on:

  • American Airlines
  • Delta Air Lines
  • United Airlines

How do I earn miles on a Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Milwaukee, WI (MKE-General Mitchell Intl.) flight with Expedia?
It's easy to earn miles on a Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Milwaukee, WI (MKE-General Mitchell Intl.) flight when you book with Expedia. Before you confirm your booking, simply select your frequent flyer program and enter your program number. As a member of One Key™, you can also earn OneKeyCash™* on top of your airline miles when you book with Expedia.*Excludes taxes and fees. OneKeyCash is not redeemable for cash and can only be used on Expedia and other participating brands.
What airports do you fly into for Milwaukee from Los Angeles - Ontario Intl. (ONT)?
If you're planning to travel to Milwaukee from Los Angeles - Ontario Intl. (ONT), you can fly into General Mitchell Intl. (MKE) Some flights may connect through major hubs like Denver Intl. (DEN), Sky Harbor Intl. (PHX), San Francisco Intl. (SFO) before reaching Milwaukee. Compare routes and airports on Expedia to find the best flight options for your travel plans.
Is it cheaper to buy a plane ticket from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Milwaukee, WI (MKE-General Mitchell Intl.) at the last minute?
Typically, booking a last minute flight from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Milwaukee, WI (MKE-General Mitchell Intl.) will be more expensive than booking in advance. As the departure date approaches, there are usually fewer seats available which can drive up the cost. However, if there's some wiggle room with your travel dates and times, you could bag a cheap last-minute fare.
Is it cheaper to book a Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Milwaukee, WI (MKE-General Mitchell Intl.) flight and hotel package?
Securing a Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Milwaukee, WI (MKE-General Mitchell Intl.) Milwaukee Vacation Packages is usually cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your travels all in one place. Select from our extensive range of stays and then add flights, activities and car rentals to your booking. Bundle everything together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Milwaukee, WI (MKE-General Mitchell Intl.)?
If you booked your Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Milwaukee, WI (MKE-General Mitchell Intl.) flight within the last 24 hours, you may be able to modify or cancel it without any fees. Depending on the airline and the type of ticket you have, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in your itinerary or confirmation email. Or, head to our Customer Service portal if you'd like more information.

Travel information

Origin airport
Ontario Intl. Airport
Destination airport
General Mitchell Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Southwest Airlines, United
Roundtrip price
$336
Distance
1707 mi

Book with confidence

Ontario Intl. Airport to Milwaukee Flights

The cheapest times to fly from Ontario Intl. Airport to Milwaukee

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Ontario Intl. Airport to Milwaukee are during the month of October. You can find some of the cheapest flights from Ontario Intl. Airport to Milwaukee with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Ontario Intl. Airport to Milwaukee

Sunday is one of the best days to book for cheap flights from Ontario Intl. Airport to Milwaukee: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from Ontario Intl. Airport to Milwaukee

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Ontario Intl. Airport to Milwaukee in 2026. You can also book with separate airlines for your outbound and return journeys, from $169 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Ontario Intl. Airport to Milwaukee flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your Ontario Intl. Airport to Milwaukee airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

Ontario Intl. Airport to Milwaukee Flights

*Flight schedules are subject to change.

*Available to One Key members.

 

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