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$143+ 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 6/26. Fares are subject to change and may not be available on all flights or dates of travel.
MKE — ONT
Jun 17 — Jun 241
Tue 6/17
Tue 6/24
1 adult, Economy
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Cheapflights Tip: The best prices from Milwaukee-Mitchell to Ontario are usually found in December or November, 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 June 12, 2025.

Round-trip from

$295
(FlightHub)

One-way from

$143
(Trip.com)

Popular in

September

Cheapest in

December

Average price

$394
From Milwaukee-Mitchell to Ontario
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One-way flight from Milwaukee-Mitchell to Ontario
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Highest demand for flights based on searches. 19% potential increase in price ($103 potential increase over avg. RT price).
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Cheapest flight prices on average. 7% potential price decrease ($30 potential savings vs. average RT price).
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Average for round-trip flights in June 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 June 12, 2025.

This FlightHub deal was found by Cheapflights users on 6/9. 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 8/157:58 pmMKE - ONT
1 stop5h 52mFrontier
Sun 8/1712:59 amONT - MKE
1 stop16h 14mFrontier
Deal found 6/9$295
This Delta deal was found by Cheapflights users on 6/10. 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.
Thu 8/144:57 pmMKE - ONT
1 stop7h 23mDelta
Mon 8/1810:00 pmONT - MKE
1 stop9h 02mDelta
Deal found 6/10$297
This American Airlines deal was found by Cheapflights users on 6/11. 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 8/145:28 pmMKE - ONT
1 stop6h 46mAmerican Airlines
Sat 8/166:17 amONT - MKE
2 stops11h 01mAmerican Airlines
Deal found 6/11$311
This Alaska Airlines deal was found by Cheapflights users on 6/12. 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.
Thu 11/63:53 pmMKE - ONT
1 stop9h 37mAlaska Airlines
Mon 11/106:11 pmONT - MKE
1 stop18h 46mAlaska Airlines
Deal found 6/12$370
This Trip.com deal was found by Cheapflights users on 6/10. 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.
Mon 6/167:56 pmMKE - ONT
1 stop5h 54mMultiple Airlines
Tue 6/247:00 amONT - MKE
1 stop11h 25mMultiple Airlines
Deal found 6/10$384
This United Airlines deal was found by Cheapflights users on 6/10. 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.
Tue 8/52:47 pmMKE - ONT
1 stop8h 07mUnited Airlines
Tue 8/121:34 pmONT - MKE
1 stop5h 40mUnited Airlines
Deal found 6/10$387
This Southwest deal was found by Cheapflights users on 6/11. 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 7/117:55 pmMKE - ONT
1 stop5h 35mSouthwest
Fri 7/189:20 pmONT - MKE
1 stop10h 15mSouthwest
Deal found 6/11$417
This Hawaiian Airlines deal was found by Cheapflights users on 6/11. 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.
Wed 7/96:30 amMKE - ONT
1 stop8h 56mHawaiian Airlines
Sun 7/1312:00 pmONT - MKE
1 stop9h 59mHawaiian Airlines
Deal found 6/11$438

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 June 12, 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 8/15

7:58 pm-11:50 pm

1 stop5h 52m

Ontario

Sun 8/17

12:59 am-7:13 pm

1 stop16h 14m

$295

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Thu 8/14

4:57 pm-10:20 pm

1 stop7h 23m

Ontario

Mon 8/18

10:00 pm-9:02 am

1 stop9h 02m

$297

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Thu 8/14

5:28 pm-10:14 pm

1 stop6h 46m

Ontario

Sat 8/16

6:17 am-7:18 pm

2 stops11h 01m

$311

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Wed 8/6

6:30 am-2:46 pm

1 stop10h 16m

Ontario

Wed 8/20

11:39 am-11:59 pm

1 stop10h 20m

$377

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Mon 6/16

7:56 pm-11:50 pm

1 stop5h 54m

Ontario

Tue 6/24

7:00 am-8:25 pm

1 stop11h 25m

$384

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Tue 8/5

2:47 pm-8:54 pm

1 stop8h 07m

Ontario

Tue 8/12

1:34 pm-9:14 pm

1 stop5h 40m

$387

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Fri 7/11

7:55 pm-11:30 pm

1 stop5h 35m

Ontario

Fri 7/18

9:20 pm-9:35 am

1 stop10h 15m

$417

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Wed 7/9

6:30 am-1:26 pm

1 stop8h 56m

Ontario

Sun 7/13

12:00 pm-11:59 pm

1 stop9h 59m

$438

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Thu 6/26

9:20 pm-11:52 am

1 stop16h 32m

$143

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Tue 8/5

6:30 am-2:46 pm

1 stop10h 16m

$148

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/11

Showing 1-10 of 15 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 June 9, 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 June 12, 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 June 12, 2025.
Peruse reviews from past customers who have flown with Alaska Airlines, Southwest 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.
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Crew

8.5

Overall

8.0

Comfort

7.8

Boarding

8.1

Food

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

Entertainment

7.1

Crew

8.5

Overall

8.0

Comfort

7.8

Boarding

8.1

Food

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
4,287 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Crew

8.5

Overall

8.0

Comfort

7.8

Boarding

8.1

Food

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
7,950 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Crew

8.5

Overall

8.0

Comfort

7.8

Boarding

8.1

Food

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
7.9
Good
2,494 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Crew

8.5

Overall

8.0

Comfort

7.8

Boarding

8.1

Food

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
8,790 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Crew

8.5

Overall

8.0

Comfort

7.8

Boarding

8.1

Food

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 $295 on this airline. Additional options worth looking into are Alaska Airlines and Delta, starting at $296 and $297 round-trip. Frontier is priced at 33% 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 Alaska Airlines ($148), Delta ($158), and Frontier ($163).

  • 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 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 June 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$138Average$277FlexibilityNo cancel feeOn-time62%
DeltaCheapest$276Average$402FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$291Average$384FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$326Average$526FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$336Average$425FlexibilityNo cancel feeOn-time63%

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