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Ontario

$151+ 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 1/20. Fares are subject to change and may not be available on all flights or dates of travel.
MKE — ONT
ene. 11 — ene. 181
dom. 1/11
dom. 1/18
1 adult, Economy
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Cheap 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 diciembre 12, 2025.

This American Airlines deal was found by Cheapflights users on 12/11. 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.
mié. 12/316:14 amMKE - ONT
2 stops11h 53mAmerican Airlines
mié. 1/710:58 amONT - MKE
1 stop9h 01mAmerican Airlines
Deal found 12/11$410
This United Airlines deal was found by Cheapflights users on 12/11. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 12/258:28 amMKE - ONT
1 stop6h 10mUnited Airlines
mar. 12/306:04 amONT - MKE
1 stop6h 48mUnited Airlines
Deal found 12/11$532
This Southwest deal was found by Cheapflights users on 12/10. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 12/305:20 amMKE - ONT
1 stop8h 20mSouthwest
lun. 1/54:15 pmONT - MKE
1 stop6h 35mSouthwest
Deal found 12/10$548
This American Airlines deal was found by Cheapflights users on 12/10. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 12/3111:54 amMKE - ONT
1 stop8h 22mAmerican Airlines
mar. 1/66:22 amONT - MKE
1 stop6h 46mAmerican Airlines
Deal found 12/10$557
This American Airlines deal was found by Cheapflights users on 12/11. 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.
mar. 12/235:51 pmMKE - ONT
1 stop16h 57mAmerican Airlines
dom. 12/2811:59 pmONT - MKE
1 stop9h 04mAmerican Airlines
Deal found 12/11$582

Find 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 diciembre 12, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$220
(Frontier)

One-way from

$151
(Delta)

Popular in

October

Cheapest in

September

Average price

$432
Provider with most accurate pricing for Milwaukee-Mitchell-Ontario flight deals.
Search Deals
Provider most trusted by Cheapflights users for Milwaukee-Mitchell-Ontario flights.
Search Deals
From Milwaukee-Mitchell to Ontario
Search Deals
One-way flight from Milwaukee-Mitchell to Ontario
Search Deals
Highest demand for flights based on searches. 8% potential increase in price ($38 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($10 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 2025
Search Deals

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 diciembre 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

jue. 2/26

3:47 pm-11:32 pm

1 stop9h 45m

Ontario

mié. 3/4

6:14 am-2:51 pm

1 stop30h 37m

$304

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

sáb. 1/10

11:30 am-9:58 pm

2 stops12h 28m

Ontario

sáb. 1/17

1:24 pm-9:21 pm

1 stop5h 57m

$339

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

mié. 1/7

5:30 am-11:31 am

1 stop8h 01m

Ontario

sáb. 1/10

1:11 pm-9:15 pm

1 stop6h 04m

$352

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

mié. 1/7

5:30 am-11:31 am

1 stop8h 01m

Ontario

vie. 1/9

1:11 pm-9:15 pm

1 stop6h 04m

$369

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

mar. 1/27

10:30 am-5:43 pm

2 stops9h 13m

Ontario

mar. 2/10

1:24 pm-10:56 pm

2 stops7h 32m

$369

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

vie. 1/30

3:53 pm-11:56 pm

1 stop10h 03m

Ontario

sáb. 2/21

6:14 am-2:51 pm

1 stop30h 37m

$388

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

jue. 1/1

5:42 pm-10:25 pm

1 stop6h 43m

Ontario

jue. 1/8

6:39 pm-10:46 am

2 stops14h 07m

$414

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

jue. 1/1

5:42 pm-10:25 pm

1 stop6h 43m

Ontario

sáb. 1/10

1:24 pm-9:21 pm

1 stop5h 57m

$424

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

jue. 1/15

3:53 pm-11:56 pm

1 stop10h 03m

Ontario

dom. 1/18

11:53 am-2:57 pm

1 stop25h 04m

$429

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

sáb. 1/10

5:00 am-12:47 pm

2 stops9h 47m

Ontario

dom. 1/18

5:05 am-3:43 pm

2 stops8h 38m

$434

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/10

Showing 1-10 of 20 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 December.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
eDreamsPrice Accuracy3 starsTrust 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 eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Milwaukee-Ontario flight deals on Cheapflights vs. eDreams >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 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 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

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

Currently, September is the cheapest month in which you can book a flight from Milwaukee to Ontario (average of $80). Flying from Milwaukee to Ontario in January is currently the most expensive (average of $120). 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 diciembre 12, 2025.

It’s typically best to fly out from Milwaukee to Ontario in the evening. Doing so could potentially save you 29% on the flight price compared to flying at noon, which is usually more expensive.

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 diciembre 12, 2025.
Read through reviews of airlines operating flights from Milwaukee to Ontario, such as Southwest, Delta, and United Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Southwest
7.9
Good
4,253 reviews

Entertainment

7.5

Food

7.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Overall

7.9

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Southwest
7.9
Good
4,253 reviews
Southwest
7.9
Good
4,253 reviews

Entertainment

7.5

Food

7.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Overall

7.9

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Delta
7.9
Good
8,008 reviews
Southwest
7.9
Good
4,253 reviews

Entertainment

7.5

Food

7.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Overall

7.9

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
United Airlines
7.4
Good
9,095 reviews
Southwest
7.9
Good
4,253 reviews

Entertainment

7.5

Food

7.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Overall

7.9

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
American Airlines
7.2
Good
11,050 reviews
Southwest
7.9
Good
4,253 reviews

Entertainment

7.5

Food

7.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Overall

7.9

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.

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.

  • How long is the flight from Milwaukee to Ontario?

    For as low as $352, Alaska Airlines can have you in Ontario from Milwaukee in 8h 01m. There are 1707 mi between Milwaukee and Ontario. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

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

    Our cheapest airline available from Milwaukee to Ontario is American Airlines. Our recent data shows that you can find tickets from as low as $278 on this airline. Additional options worth looking into are Delta and Southwest, starting at $326 and $342 round-trip. American Airlines is priced at 36% 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 ($129), American Airlines ($159), and Southwest ($183).

  • 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, September is the cheapest month in which you can book a flight from Milwaukee to Ontario (average of $80). Flying from Milwaukee to Ontario in January is currently the most expensive (average of $120). 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 diciembre 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$278Average$368FlexibilityNo cancel feeOn-time71%
DeltaCheapest$326Average$407FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$342Average$426FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$344Average$526FlexibilityNo cancel feeOn-time69%

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