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$105+ 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 5/10. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — MKE
Apr 27 — May 41
Sun 4/27
Sun 5/4
1 adult, Economy
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Cheapflights Tip: The best prices from Ontario to Milwaukee-Mitchell are usually found in November or January, booked 51 days in advance, depart on a Wednesday or Saturday and return on a Wednesday

Cheap 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 April 22, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$211
(CheapOair)

One-way from

$105
(Frontier)

Popular in

July

Cheapest in

November

Average price

$473
Provider with most accurate pricing for Ontario-Milwaukee-Mitchell flight deals.
Search Deals
Provider most trusted by Cheapflights users for Ontario-Milwaukee-Mitchell flights.
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From Ontario to Milwaukee-Mitchell
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One-way flight from Ontario to Milwaukee-Mitchell
Search Deals
Highest demand for flights based on searches. 10% potential increase in price ($50 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($8 potential savings vs. average RT price).
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Average for round-trip flights in April 2025
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Find 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 April 22, 2025.

This CheapOair deal was found by Cheapflights users on 4/22. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/285:21 pmONT - MKE
1 stop23h 39mFrontier
Mon 6/27:56 pmMKE - ONT
1 stop16h 47mFrontier
Deal found 4/22$211
This Delta deal was found by Cheapflights users on 4/21. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/101:15 pmONT - MKE
1 stop7h 00mDelta
Tue 6/177:20 amMKE - ONT
1 stop6h 57mDelta
Deal found 4/21$325
This Alaska Airlines deal was found by Cheapflights users on 4/21. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/811:39 amONT - MKE
1 stop10h 20mAlaska Airlines
Tue 9/167:00 amMKE - ONT
1 stop9h 06mAlaska Airlines
Deal found 4/21$342
This American Airlines deal was found by Cheapflights users on 4/21. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/78:01 pmONT - MKE
2 stops11h 33mAmerican Airlines
Thu 8/1410:57 amMKE - ONT
1 stop10h 50mAmerican Airlines
Deal found 4/21$348
This Trip.com deal was found by Cheapflights users on 4/22. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/1510:52 amONT - MKE
2 stops18h 51mMultiple Airlines
Sun 5/184:25 pmMKE - ONT
1 stop9h 34mMultiple Airlines
Deal found 4/22$364
This United Airlines deal was found by Cheapflights users on 4/20. 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.
Fri 7/251:34 pmONT - MKE
1 stop5h 41mUnited Airlines
Tue 7/292:47 pmMKE - ONT
1 stop8h 07mUnited Airlines
Deal found 4/20$380
This Southwest deal was found by Cheapflights users on 4/21. 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 6/275:05 pmONT - MKE
1 stop6h 10mSouthwest
Mon 7/76:10 amMKE - ONT
1 stop9h 20mSouthwest
Deal found 4/21$432
This Hawaiian Airlines deal was found by Cheapflights users on 4/21. 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 Hawaiian Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/311:39 amONT - MKE
1 stop10h 20mHawaiian Airlines
Mon 10/62:36 pmMKE - ONT
1 stop10h 01mHawaiian Airlines
Deal found 4/21$580

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 April 22, 2025.
Use the filters below to find and compare flights from Ontario to Milwaukee that are best for you.

Fly from

Ontario

Fly to

Milwaukee

Route

Depart

Return

Price

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Wed 5/28

5:21 pm-7:00 pm

1 stop23h 39m

Milwaukee-Mitchell

Mon 6/2

7:56 pm-10:43 am

1 stop16h 47m

$211

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Tue 6/10

1:15 pm-10:15 pm

1 stop7h 00m

Milwaukee-Mitchell

Tue 6/17

7:20 am-12:17 pm

1 stop6h 57m

$325

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Mon 9/8

11:39 am-11:59 pm

1 stop10h 20m

Milwaukee-Mitchell

Tue 9/16

7:00 am-2:06 pm

1 stop9h 06m

$342

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Thu 8/7

8:01 pm-9:34 am

2 stops11h 33m

Milwaukee-Mitchell

Thu 8/14

10:57 am-7:47 pm

1 stop10h 50m

$348

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Thu 5/15

10:52 am-7:43 am

2 stops18h 51m

Milwaukee-Mitchell

Sun 5/18

4:25 pm-11:59 pm

1 stop9h 34m

$364

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Fri 7/25

1:34 pm-9:15 pm

1 stop5h 41m

Milwaukee-Mitchell

Tue 7/29

2:47 pm-8:54 pm

1 stop8h 07m

$380

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Fri 6/27

5:05 pm-1:15 am

1 stop6h 10m

Milwaukee-Mitchell

Mon 7/7

5:00 am-10:25 am

2 stops7h 25m

$432

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Fri 10/3

11:39 am-11:59 pm

1 stop10h 20m

Milwaukee-Mitchell

Mon 10/6

2:36 pm-10:37 pm

1 stop10h 01m

$580

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Sat 5/10

12:59 am-3:25 pm

1 stop12h 26m

$105

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Wed 5/21

11:51 am-11:59 pm

1 stop10h 08m

$153

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/22

Showing 1-10 of 15 results
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 April.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*2 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
CheapfaremartPrice Accuracy-Trust Score*1 star
CheapOairPrice Accuracy1 starTrust Score*3 stars

*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 eDreams the most. eDreams 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

How far ahead should I book a flight from Ontario to Milwaukee?

Use this chart to determine the optimal time to book a round-trip flight from Ontario to Milwaukee. Price data was last updated on April 18, 2025.

The best time to book flights from Ontario to Milwaukee is 50 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

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

Currently, February is the cheapest month in which you can book a flight from Ontario to Milwaukee (average of $280). Flying from Ontario to Milwaukee in June is currently the most expensive (average of $376). 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.

What is the cheapest time of day to fly from ONT to MKE?

Find hourly flight availability from Ontario to Milwaukee. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated April 22, 2025.

One of the essential ways to save on airfare from Ontario to Milwaukee is to remain as flexible as possible. Flights that are at noon tend to be the most expensive. A flight in the evening could potentially save you up to 33% on airfare.

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

Use this chart to determine the cheapest time to fly round-trip from Ontario to Milwaukee. Price data was last updated on December 16, 2024.

Travelers seeking maximum savings on their Ontario to Milwaukee flight should consider departing on Saturday evenings when fares are most often at their lowest. Sunday mornings flights should be avoided if possible as fares are typically the most expensive at this time.

Rainfall in Milwaukee by month

Plan your trip to Milwaukee by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Milwaukee ranges from 1.4 - 4.0 inches per month. June is typically the wettest month, when rainfall can reach 4.0 in. January is typically the driest time to visit Milwaukee when rainfall is around 1.4 in.

Temperature in Milwaukee by month

Plan your trip to Milwaukee by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Milwaukee, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 73.4 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 21.2 F).

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 April 22, 2025.
See what other customers who have flown with Alaska Airlines, Southwest and Delta from Ontario to Milwaukee have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
9,906 reviews

Crew

8.5

Boarding

8.2

Entertainment

7.1

Comfort

7.9

Food

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Alaska Airlines
8.0
Very good
9,906 reviews
Alaska Airlines
8.0
Very good
9,906 reviews

Crew

8.5

Boarding

8.2

Entertainment

7.1

Comfort

7.9

Food

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Southwest
8.0
Very good
4,286 reviews
Alaska Airlines
8.0
Very good
9,906 reviews

Crew

8.5

Boarding

8.2

Entertainment

7.1

Comfort

7.9

Food

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Delta
8.0
Very good
7,920 reviews
Alaska Airlines
8.0
Very good
9,906 reviews

Crew

8.5

Boarding

8.2

Entertainment

7.1

Comfort

7.9

Food

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Hawaiian Airlines
7.9
Good
2,392 reviews
Alaska Airlines
8.0
Very good
9,906 reviews

Crew

8.5

Boarding

8.2

Entertainment

7.1

Comfort

7.9

Food

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
United Airlines
7.4
Good
8,683 reviews
Alaska Airlines
8.0
Very good
9,906 reviews

Crew

8.5

Boarding

8.2

Entertainment

7.1

Comfort

7.9

Food

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

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.

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

    Frontier, at $211, was found to be the cheapest airline from Ontario to Milwaukee.Alternate airlines to your destination round-trip include Delta and Alaska Airlines. Frontier is currently priced 49% 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 Frontier. According to our data, you can fly for as low as $105. Users have also found prices from $153 and $172 on Alaska Airlines and Delta, 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, February is the cheapest month in which you can book a flight from Ontario to Milwaukee (average of $280). Flying from Ontario to Milwaukee in June is currently the most expensive (average of $376). 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 Ontario?

Book flights to Ontario if you plan to visit one of these locations
Mequon
Pewaukee
Sheboygan
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 5 airlines flying from Ontario to Milwaukee

Discover the top 5 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 April 22, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$140Average$226FlexibilityNo cancel feeOn-time62%
American AirlinesCheapest$308Average$443FlexibilityNo cancel feeOn-time71%
DeltaCheapest$324Average$371FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$326Average$418FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$406Average$514FlexibilityNo cancel feeOn-time69%

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