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Milwaukee

$162+ Cheap flights from Ontario to Milwaukee (ONT - MKE)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 9/30. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — MKE
Aug 22 — Aug 291
Sat 8/22
Sat 8/29
1 adult, Economy
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Cheap flight deals from Ontario to Milwaukee

Cheapest flights from Ontario to Milwaukee
Explore the most affordable flight options available from Ontario to Milwaukee. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 23, 2026.

This Southwest deal was found by Cheapflights users on 7/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/510:15 am
ONT
-
MKE
1 stop7h 30m
Southwest
Sat 9/125:00 pm
MKE
-
ONT
1 stop5h 50m
Southwest
Deal found 7/20$323
This United Airlines deal was found by Cheapflights users on 7/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/67:00 am
ONT
-
MKE
1 stop7h 10m
United Airlines
Sat 9/1210:30 am
MKE
-
ONT
2 stops11h 31m
United Airlines
Deal found 7/20$328
This American Airlines deal was found by Cheapflights users on 7/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/68:01 pm
ONT
-
MKE
2 stops12h 56m
American Airlines
Sat 9/127:01 am
MKE
-
ONT
2 stops13h 16m
American Airlines
Deal found 7/22$333
This Southwest deal was found by Cheapflights users on 7/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/3012:40 pm
ONT
-
MKE
2 stops8h 25m
Southwest
Mon 11/23:55 pm
MKE
-
ONT
2 stops8h 00m
Southwest
Deal found 7/21$338
This CheapOair deal was found by Cheapflights users on 7/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/136:02 am
ONT
-
MKE
1 stop15h 57m
Alaska Airlines
Mon 8/176:02 am
MKE
-
ONT
1 stop9h 07m
Alaska Airlines
Deal found 7/20$359
This American Airlines deal was found by Cheapflights users on 7/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/56:15 am
ONT
-
MKE
2 stops12h 45m
American Airlines
Fri 9/1111:37 am
MKE
-
ONT
2 stops8h 40m
American Airlines
Deal found 7/20$361
This Southwest deal was found by Cheapflights users on 7/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/2510:55 am
ONT
-
MKE
1 stop5h 35m
Southwest
Sat 8/291:30 pm
MKE
-
ONT
2 stops9h 20m
Southwest
Deal found 7/20$364
This United Airlines deal was found by Cheapflights users on 7/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/511:00 am
ONT
-
MKE
2 stops9h 36m
United Airlines
Sat 9/122:20 pm
MKE
-
ONT
2 stops8h 33m
United Airlines
Deal found 7/20$370

Find flight deals from Ontario to Milwaukee

Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) to Milwaukee (MKE). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated July 23, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$323
(American Airlines)

One-way from

$162
(American Airlines)

Popular in

August

Cheapest in

September

Average price

$566
Provider with most accurate pricing for Ontario-Milwaukee-Mitchell flight deals.
Search Deals
Provider most trusted by Cheapflights users for Ontario-Milwaukee-Mitchell flights.
Search Deals
From Ontario to Milwaukee-Mitchell
Search Deals
One-way flight from Ontario to Milwaukee-Mitchell
Search Deals
Highest demand for flights based on searches. 13% potential increase in price ($76 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 5% potential price decrease ($27 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in July 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Ontario to Milwaukee that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated July 23, 2026.
Use the filters below to find and compare flights from Ontario to Milwaukee that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Sat 9/5

9:25 am-6:45 pm

1 stop7h 20m

Milwaukee-Mitchell

Sat 9/12

1:30 pm-8:05 pm

2 stops8h 35m

$328

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Fri 9/11

1:04 pm-9:11 pm

1 stop6h 07m

Milwaukee-Mitchell

Mon 9/14

4:49 pm-10:24 pm

1 stop7h 35m

$341
Quickest round-trip

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Sat 8/15

7:05 am-4:20 pm

1 stop7h 15m

Milwaukee-Mitchell

Mon 8/17

6:20 pm-10:05 pm

1 stop5h 45m

$359

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Wed 9/2

6:40 am-2:55 pm

1 stop6h 15m

Milwaukee-Mitchell

Wed 9/9

2:05 pm-6:55 pm

1 stop6h 50m

$359

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Wed 9/2

1:18 pm-9:03 pm

1 stop5h 45m

Milwaukee-Mitchell

Wed 9/9

5:00 am-12:50 pm

2 stops9h 50m

$364

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Wed 9/9

1:10 pm-9:25 pm

1 stop6h 15m

Milwaukee-Mitchell

Sun 9/13

5:25 am-11:45 am

1 stop8h 20m

$405

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Tue 10/20

1:35 pm-9:55 pm

1 stop6h 20m

Milwaukee-Mitchell

Fri 10/23

5:00 pm-11:55 pm

2 stops8h 55m

$410

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Sat 10/24

6:00 am-5:13 pm

1 stop9h 13m

Milwaukee-Mitchell

Tue 10/27

2:40 pm-8:56 pm

1 stop8h 16m

$423

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Sun 9/6

12:00 pm-11:53 pm

1 stop9h 53m

Milwaukee-Mitchell

Thu 9/10

7:30 am-12:14 pm

1 stop6h 44m

$439

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Sun 8/16

5:00 am-1:29 pm

1 stop6h 29m

Milwaukee-Mitchell

Sat 8/22

1:19 pm-8:53 pm

2 stops9h 34m

$440

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/20

Showing 1-10 of 20 resultsSorted by cheapest first
1
2

Compare providers for flights from Ontario to Milwaukee

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Ontario to Milwaukee in July.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
JustAirTicketPrice Accuracy-Trust Score*1 star

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Ontario-Milwaukee flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Ontario-Milwaukee flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Ontario-Milwaukee flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Ontario-Milwaukee flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Ontario-Milwaukee flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Ontario to Milwaukee

Have a flexible travel schedule? Discover the best time to fly to Milwaukee from Ontario with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

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

What is the cheapest month to book a flight from Ontario to Milwaukee?

Currently, September is the cheapest month in which you can book a flight from Ontario to Milwaukee (average of $366). Flying from Ontario to Milwaukee in August is currently the most expensive (average of $779). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

Reviews of airlines servicing Milwaukee

Get insights into the airlines that provide service to Milwaukee. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Milwaukee. Reviews last updated July 23, 2026.
Read reviews from past customers who have flown Southwest,United Airlines, andAmerican Airlines from Ontario to Milwaukee. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,238 reviews

Food

7.0

Boarding

8.1

Crew

8.6

Comfort

8.0

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
Southwest
8.0
Very good
4,238 reviews
Southwest
8.0
Very good
4,238 reviews

Food

7.0

Boarding

8.1

Crew

8.6

Comfort

8.0

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
United Airlines
7.4
Good
10,025 reviews
Southwest
8.0
Very good
4,238 reviews

Food

7.0

Boarding

8.1

Crew

8.6

Comfort

8.0

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
American Airlines
7.1
Good
11,834 reviews
Southwest
8.0
Very good
4,238 reviews

Food

7.0

Boarding

8.1

Crew

8.6

Comfort

8.0

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.

Related info for your journey

Find useful and relevant information for your journey from Ontario to Milwaukee. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How long is the flight from Ontario to Milwaukee?

    A quick flight from Ontario to Milwaukee can take about 7h 10m. Southwest provides one of the quickest options available for as low as $328. The distance between Ontario and Milwaukee is about 1707 mi. Both multi-stop and nonstop flights can be found to your destination and back.

  • What are the cheapest airlines flying from Ontario to Milwaukee round-trip?

    American Airlines, at $276, was found to be the cheapest airline from Ontario to Milwaukee.Alternate airlines to your destination round-trip include United Airlines and Southwest. American Airlines is currently priced 44% below the average price you’ll pay for this route.

  • What are the cheapest airlines to fly from Ontario to Milwaukee one-way?

    For one-way options, check prices for Delta. According to our data, you can fly for as low as $138. Users have also found prices from $144 and $179 on United Airlines and American Airlines, respectively.

  • Can I find deals for flights from Ontario to Milwaukee that include hotel bookings?

    Yes. In addition to deals on Ontario to Milwaukee flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Ontario to Milwaukee?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Ontario to Milwaukee.

  • Can I find deals for business class flights from Ontario to Milwaukee?

    Yes. Cheapflights offers flight deals from Ontario to Milwaukee by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Ontario to Milwaukee?

    Currently, September is the cheapest month in which you can book a flight from Ontario to Milwaukee (average of $366). Flying from Ontario to Milwaukee in August is currently the most expensive (average of $779). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Traveling to a place near Milwaukee?

Book flights to Milwaukee if you plan to visit one of these locations
Sheboygan
Port Washington
New Berlin
Oak Creek
Wauwatosa

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Alternative routes for Ontario to Milwaukee

See prices for flight routes from nearby airports that may be better suited for you.
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Top 3 airlines flying from Ontario to Milwaukee

Discover the top 3 airlines that operate flights from Ontario to Milwaukee. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated July 23, 2026.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$276Average$437FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$309Average$440FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$350Average$493FlexibilityNo cancel feeOn-time63%

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