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$145+ Cheap flights from Milwaukee to Ontario (MKE - ONT)

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 5/8. Fares are subject to change and may not be available on all flights or dates of travel.
MKE — ONT
Mar 31 — Apr 71
Mon 3/31
Mon 4/7
1 adult, Economy
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Cheapflights Tip: The best prices from Milwaukee-Mitchell to Ontario are usually found in May or July, booked 18 days in advance, depart on a Wednesday or Saturday and return on a Wednesday

Cheap flight deals from Milwaukee to Ontario

Discover tips and strategies to find the most affordable flight options for your journey from Milwaukee (MKE) to Ontario (ONT). 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 March 26, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$288
(Frontier)

One-way from

$145
(Frontier)

Popular in

September

Cheapest in

May

Average price

$398
Provider with most accurate pricing for Milwaukee-Mitchell-Ontario flight deals.
Search Deals
Provider most trusted by Cheapflights users for Milwaukee-Mitchell-Ontario flights.
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From Milwaukee-Mitchell to Ontario
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One-way flight from Milwaukee-Mitchell to Ontario
Search Deals
Highest demand for flights based on searches. 23% potential increase in price ($125 potential increase over avg. RT price).
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Cheapest flight prices on average. 8% potential price decrease ($32 potential savings vs. average RT price).
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Average for round-trip flights in March 2025
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Find flight deals from Milwaukee to Ontario

Cheapest flights from Milwaukee to Ontario
Explore the most affordable flight options available from Milwaukee to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 26, 2025.

This Frontier deal was found by Cheapflights users on 3/25. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/83:48 pmMKE - ONT
1 stop10h 11mFrontier
Sat 5/1012:59 amONT - MKE
1 stop12h 26mFrontier
Deal found 3/25$288
This Southwest deal was found by Cheapflights users on 3/25. 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 4/227:05 pmMKE - ONT
1 stop5h 55mSouthwest
Thu 4/242:55 pmONT - MKE
1 stop7h 15mSouthwest
Deal found 3/25$343
This Delta deal was found by Cheapflights users on 3/25. 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.
Sun 4/2012:31 pmMKE - ONT
1 stop8h 57mDelta
Thu 4/2412:07 pmONT - MKE
1 stop7h 46mDelta
Deal found 3/25$345
This American Airlines deal was found by Cheapflights users on 3/25. 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.
Wed 7/1610:05 amMKE - ONT
2 stops10h 03mAmerican Airlines
Tue 7/2212:55 pmONT - MKE
2 stops8h 08mAmerican Airlines
Deal found 3/25$357
This United Airlines deal was found by Cheapflights users on 3/25. 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.
Thu 5/82:04 pmMKE - ONT
1 stop9h 56mUnited Airlines
Sun 5/114:15 pmONT - MKE
1 stop5h 43mUnited Airlines
Deal found 3/25$380
This Orbitz deal was found by Cheapflights users on 3/25. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/229:58 amMKE - ONT
2 stops12h 31mMultiple Airlines
Wed 4/2312:59 amONT - MKE
1 stop11h 12mMultiple Airlines
Deal found 3/25$386
This Alaska Airlines deal was found by Cheapflights users on 3/25. 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.
Tue 4/223:06 pmMKE - ONT
1 stop26h 26mAlaska Airlines
Tue 4/296:00 amONT - MKE
1 stop30h 06mAlaska Airlines
Deal found 3/25$422

Cheapflights Fare Finder

Customize your flight search to find flights from Milwaukee to Ontario 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 March 26, 2025.
Use the filters below to find and compare flights from Milwaukee to Ontario that are best for you.

Fly from

Milwaukee

Fly to

Ontario

Route

Depart

Return

Price

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Thu 5/8

3:48 pm-11:59 pm

1 stop10h 11m

Ontario

Sat 5/10

12:59 am-3:25 pm

1 stop12h 26m

$288

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Tue 4/22

7:05 am-12:16 pm

1 stop7h 11m

Ontario

Sat 4/26

10:15 pm-9:08 am

1 stop8h 53m

$343

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Tue 4/22

3:55 pm-10:30 pm

2 stops8h 35m

Ontario

Thu 4/24

2:55 pm-12:10 am

1 stop7h 15m

$348

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Wed 7/16

10:05 am-6:08 pm

2 stops10h 03m

Ontario

Tue 7/22

12:55 pm-11:03 pm

2 stops8h 08m

$357

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Thu 5/8

2:04 pm-10:00 pm

1 stop9h 56m

Ontario

Sun 5/11

4:15 pm-11:58 pm

1 stop5h 43m

$380

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Tue 4/22

9:58 am-8:29 pm

2 stops12h 31m

Ontario

Wed 4/23

12:59 am-2:11 pm

1 stop11h 12m

$386

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Tue 4/22

3:06 pm-3:32 pm

1 stop26h 26m

Ontario

Tue 4/29

6:00 am-2:06 pm

1 stop30h 06m

$422

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Thu 5/8

3:48 pm-11:59 pm

1 stop10h 11m

$145

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Wed 4/23

7:05 am-12:16 pm

1 stop7h 11m

$172

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Fri 5/2

3:06 pm-11:59 pm

1 stop10h 53m

$196

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/25

Showing 1-10 of 12 results
1
2

Compare providers for flights from Milwaukee to Ontario

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 Milwaukee to Ontario in March.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
PricelinePrice 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 Milwaukee-Ontario flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Milwaukee-Ontario flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Milwaukee-Ontario flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Milwaukee-Ontario 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 Milwaukee-Ontario 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 Milwaukee to Ontario

Have a flexible travel schedule? Discover the best time to fly to Ontario from Milwaukee 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 Milwaukee to Ontario

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

Use this chart to determine the optimal time to book a round-trip flight from Milwaukee to Ontario. Price data was last updated on March 21, 2025.

Booking 18 days in advance of your planned departure date is, on average, the best time to get cheap flights from Milwaukee to Ontario. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

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

Currently, August is the cheapest month in which you can book a flight from Milwaukee to Ontario (average of $246). Flying from Milwaukee to Ontario in March is currently the most expensive (average of $326). 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 MKE to ONT?

Find hourly flight availability from Milwaukee to Ontario. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated March 26, 2025.

It’s typically best to fly out from Milwaukee to Ontario in the evening. Doing so could potentially save you 30% on the flight price compared to flying at noon, which is usually more expensive.

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

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

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

Rainfall in Ontario by month

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

In terms of precipitation, rainfall in Ontario ranges from 0.1 - 3.4 inches per month. February is typically the wettest month, when rainfall can reach 3.4 in. June is typically the driest time to visit Ontario when rainfall is around 0.1 in.

Temperature in Ontario by month

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

If weather is an important factor for your trip to Ontario, use this chart to help with planning. For those seeking warmer temperatures, August is the ideal time of year to visit, when temperatures reach an average of 78.8 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 53.6 F).

Reviews of airlines servicing Ontario

Get insights into the airlines that provide service to Ontario. 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 Ontario. Reviews last updated March 26, 2025.
Peruse reviews from past customers who have flown with Southwest, Alaska Airlines and Delta from Milwaukee to Ontario to help guide your decision. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.1
Very good
4,274 reviews

Overall

8.1

Boarding

8.2

Comfort

8.1

Entertainment

7.6

Food

7.1

Crew

8.6

Reviews

1 / 20
10.0
Excellent

Merlyn,Feb 2025

LAX - SMF

New Terminal is neat, lost of stores and places to catch a bite.
Southwest
8.1
Very good
4,274 reviews
Southwest
8.1
Very good
4,274 reviews

Overall

8.1

Boarding

8.2

Comfort

8.1

Entertainment

7.6

Food

7.1

Crew

8.6

Reviews

1 / 20
10.0
Excellent

Merlyn,Feb 2025

LAX - SMF

New Terminal is neat, lost of stores and places to catch a bite.
Alaska Airlines
8.0
Very good
9,789 reviews
Southwest
8.1
Very good
4,274 reviews

Overall

8.1

Boarding

8.2

Comfort

8.1

Entertainment

7.6

Food

7.1

Crew

8.6

Reviews

1 / 20
10.0
Excellent

Merlyn,Feb 2025

LAX - SMF

New Terminal is neat, lost of stores and places to catch a bite.
Delta
8.0
Very good
7,891 reviews
Southwest
8.1
Very good
4,274 reviews

Overall

8.1

Boarding

8.2

Comfort

8.1

Entertainment

7.6

Food

7.1

Crew

8.6

Reviews

1 / 20
10.0
Excellent

Merlyn,Feb 2025

LAX - SMF

New Terminal is neat, lost of stores and places to catch a bite.
Hawaiian Airlines
7.9
Good
2,330 reviews
Southwest
8.1
Very good
4,274 reviews

Overall

8.1

Boarding

8.2

Comfort

8.1

Entertainment

7.6

Food

7.1

Crew

8.6

Reviews

1 / 20
10.0
Excellent

Merlyn,Feb 2025

LAX - SMF

New Terminal is neat, lost of stores and places to catch a bite.
United Airlines
7.4
Good
8,608 reviews
Southwest
8.1
Very good
4,274 reviews

Overall

8.1

Boarding

8.2

Comfort

8.1

Entertainment

7.6

Food

7.1

Crew

8.6

Reviews

1 / 20
10.0
Excellent

Merlyn,Feb 2025

LAX - SMF

New Terminal is neat, lost of stores and places to catch a bite.

Related info for your journey

Find useful and relevant information for your journey from Milwaukee to Ontario. 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 Milwaukee to Ontario round-trip?

    Our cheapest airline available from Milwaukee to Ontario is Frontier. Our recent data shows that you can find tickets from as low as $288 on this airline. Additional options worth looking into are Delta and Southwest, starting at $343 and $348 round-trip. Frontier is priced at 30% lower than the current average price of a flight leaving 3 months from now.

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

    The cheapest airlines for a one-way flight from Milwaukee to Ontario are Frontier ($145), Delta ($172), and Hawaiian Airlines ($196).

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Milwaukee to Ontario 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 Milwaukee to Ontario?

    Currently, August is the cheapest month in which you can book a flight from Milwaukee to Ontario (average of $246). Flying from Milwaukee to Ontario in March is currently the most expensive (average of $326). 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

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Top 5 airlines flying from Milwaukee to Ontario

Discover the top 5 airlines that operate flights from Milwaukee to Ontario. 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 March 26, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$138Average$205FlexibilityNo cancel feeOn-time62%
DeltaCheapest$276Average$402FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$291Average$390FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$326Average$536FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$326Average$424FlexibilityNo cancel feeOn-time63%
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