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$122+ 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 10/13. Fares are subject to change and may not be available on all flights or dates of travel.
MKE — ONT
Aug 4 — Aug 111
Mon 8/4
Mon 8/11
1 adult, Economy
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Cheapflights Tip: The best prices from Milwaukee-Mitchell to Ontario are usually found in November or December, booked 13 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 July 30, 2025.

Round-trip from

$265
(FlightHub)

One-way from

$122
(Cheapflightsfares)

Popular in

September

Cheapest in

November

Average price

$436
From Milwaukee-Mitchell to Ontario
Search Deals
One-way flight from Milwaukee-Mitchell to Ontario
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Highest demand for flights based on searches. 16% potential increase in price ($90 potential increase over avg. RT price).
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Cheapest flight prices on average. 7% potential price decrease ($29 potential savings vs. average RT price).
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Average for round-trip flights in July 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 July 30, 2025.

This FlightHub deal was found by Cheapflights users on 7/30. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/228:02 pmMKE - ONT
1 stop5h 48mFrontier
Sun 8/245:09 pmONT - MKE
1 stop24h 03mFrontier
Deal found 7/30$265
This American Airlines deal was found by Cheapflights users on 7/29. 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 8/232:31 pmMKE - ONT
1 stop5h 21mAmerican Airlines
Sat 8/306:17 amONT - MKE
1 stop5h 39mAmerican Airlines
Deal found 7/29$324
This Delta deal was found by Cheapflights users on 7/28. 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 10/1412:06 pmMKE - ONT
1 stop9h 13mDelta
Wed 10/2210:29 pmONT - MKE
1 stop8h 57mDelta
Deal found 7/28$325
This Alaska Airlines deal was found by Cheapflights users on 7/29. 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.
Wed 9/36:27 amMKE - ONT
1 stop9h 45mAlaska Airlines
Mon 9/811:39 amONT - MKE
1 stop10h 23mAlaska Airlines
Deal found 7/29$331
This Southwest deal was found by Cheapflights users on 7/30. 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.
Thu 9/252:15 pmMKE - ONT
2 stops8h 50mSouthwest
Mon 9/2912:45 pmONT - MKE
1 stop8h 15mSouthwest
Deal found 7/30$392
This United Airlines deal was found by Cheapflights users on 7/28. 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.
Wed 10/82:35 pmMKE - ONT
1 stop7h 49mUnited Airlines
Tue 10/145:05 amONT - MKE
1 stop5h 56mUnited Airlines
Deal found 7/28$415

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 July 30, 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

Fri 8/22

8:02 pm-11:50 pm

1 stop5h 48m

Ontario

Sat 8/23

12:59 am-7:12 pm

1 stop16h 13m

$265

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Sat 8/23

2:31 pm-5:52 pm

1 stop5h 21m

Ontario

Sat 8/30

6:17 am-1:56 pm

1 stop5h 39m

$324

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Thu 9/4

3:20 pm-12:03 am

1 stop10h 43m

Ontario

Tue 9/9

11:39 am-12:02 am

1 stop10h 23m

$330

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Thu 8/28

12:15 pm-7:11 pm

1 stop8h 56m

Ontario

Mon 9/1

11:45 am-11:36 pm

1 stop9h 51m

$337

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Thu 9/25

2:15 pm-9:05 pm

2 stops8h 50m

Ontario

Mon 9/29

12:45 pm-11:00 pm

1 stop8h 15m

$392

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Tue 8/26

3:44 pm-10:30 pm

1 stop8h 46m

Ontario

Sat 8/30

1:19 pm-9:11 pm

1 stop5h 52m

$415

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Mon 10/13

7:57 pm-11:50 pm

1 stop5h 53m

$122

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Wed 9/3

6:27 am-2:12 pm

1 stop9h 45m

$162

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Sat 9/6

6:14 am-1:54 pm

1 stop9h 40m

$163

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Mon 12/8

2:36 pm-10:37 pm

1 stop10h 01m

$188

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/29

Showing 1-10 of 14 results
1
2

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 July 25, 2025.

Booking 13 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 $328). 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 July 30, 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.

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 July 30, 2025.
Read through reviews of airlines operating flights from Milwaukee to Ontario, such as Alaska Airlines, Southwest, and Delta. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Crew

8.5

Food

7.1

Boarding

8.1

Comfort

7.8

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Alaska Airlines
8.0
Very good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Crew

8.5

Food

7.1

Boarding

8.1

Comfort

7.8

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Southwest
8.0
Very good
4,241 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Crew

8.5

Food

7.1

Boarding

8.1

Comfort

7.8

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Delta
8.0
Very good
7,980 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Crew

8.5

Food

7.1

Boarding

8.1

Comfort

7.8

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Hawaiian Airlines
7.8
Good
2,611 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Crew

8.5

Food

7.1

Boarding

8.1

Comfort

7.8

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
United Airlines
7.4
Good
8,896 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Crew

8.5

Food

7.1

Boarding

8.1

Comfort

7.8

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

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 $265 on this airline. Additional options worth looking into are American Airlines and Delta, starting at $324 and $325 round-trip. Frontier is priced at 40% 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 ($122), Hawaiian Airlines ($162), and American Airlines ($168).

  • 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 $328). 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 4 airlines flying from Milwaukee to Ontario

Discover the top 4 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 July 30, 2025.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$291Average$383FlexibilityNo cancel feeOn-time71%
DeltaCheapest$326Average$467FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$330Average$424FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$342Average$536FlexibilityNo cancel feeOn-time69%

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