HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Ontario

$117+ 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 11/14. Fares are subject to change and may not be available on all flights or dates of travel.
MKE — ONT
Nov 28 — Dec 51
Fri 11/28
Fri 12/5
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Milwaukee to Ontario with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

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 October 29, 2025.

This Mytrip deal was found by Cheapflights users on 10/27. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/78:04 pmMKE - ONT
1 stop17h 06mFrontier
Mon 11/106:53 amONT - MKE
1 stop10h 26mFrontier
Deal found 10/27$237
This Mytrip deal was found by Cheapflights users on 10/27. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/178:04 pmMKE - ONT
1 stop27h 23mFrontier
Fri 11/217:48 pmONT - MKE
1 stop21h 21mFrontier
Deal found 10/27$256
This Delta deal was found by Cheapflights users on 10/27. 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.
Wed 12/105:11 pmMKE - ONT
1 stop7h 53mDelta
Wed 12/311:15 pmONT - MKE
1 stop6h 33mDelta
Deal found 10/27$320
This Delta deal was found by Cheapflights users on 10/27. 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.
Sat 12/137:20 amMKE - ONT
1 stop7h 14mDelta
Wed 12/311:15 pmONT - MKE
1 stop6h 33mDelta
Deal found 10/27$328
This Delta deal was found by Cheapflights users on 10/27. 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.
Wed 12/177:20 amMKE - ONT
1 stop7h 14mDelta
Tue 1/61:04 pmONT - MKE
1 stop8h 26mDelta
Deal found 10/27$351
This Delta deal was found by Cheapflights users on 10/27. 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.
Wed 12/311:41 amMKE - ONT
1 stop9h 58mDelta
Mon 12/810:25 pmONT - MKE
2 stops12h 07mDelta
Deal found 10/27$356
This Delta deal was found by Cheapflights users on 10/27. 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 11/279:36 amMKE - ONT
2 stops12h 06mDelta
Mon 12/110:25 pmONT - MKE
1 stop9h 03mDelta
Deal found 10/27$361
This American Airlines deal was found by Cheapflights users on 10/27. 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.
Sun 12/2111:54 amMKE - ONT
1 stop8h 22mAmerican Airlines
Sat 1/176:00 amONT - MKE
1 stop9h 05mAmerican Airlines
Deal found 10/27$363
This Delta deal was found by Cheapflights users on 10/29. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/137:20 amMKE - ONT
1 stop7h 14mDelta
Sat 1/101:10 pmONT - MKE
1 stop6h 22mDelta
Deal found 10/29$367

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 October 29, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$256
(Mytrip)

One-way from

$117
(Frontier)

Popular in

October

Cheapest in

September

Average price

$716
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. 10% potential increase in price ($53 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 6% potential price decrease ($26 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in October 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 October 29, 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

Wed 12/10

5:11 pm-11:04 pm

1 stop7h 53m

Ontario

Wed 12/31

1:15 pm-9:48 pm

1 stop6h 33m

$320

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Thu 12/11

3:17 pm-11:04 pm

1 stop9h 47m

Ontario

Wed 12/31

1:15 pm-9:48 pm

1 stop6h 33m

$330

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Tue 12/16

7:20 am-12:34 pm

1 stop7h 14m

Ontario

Wed 12/31

1:15 pm-9:48 pm

1 stop6h 33m

$330

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Sat 12/13

7:20 am-12:34 pm

1 stop7h 14m

Ontario

Wed 12/31

1:15 pm-9:48 pm

1 stop6h 33m

$338

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Wed 12/3

3:17 pm-11:04 pm

1 stop9h 47m

Ontario

Mon 12/8

1:29 pm-9:46 pm

1 stop6h 17m

$351

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Wed 12/17

7:20 am-12:34 pm

1 stop7h 14m

Ontario

Wed 1/7

10:30 pm-9:17 am

1 stop8h 47m

$351

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Wed 12/17

7:20 am-12:34 pm

1 stop7h 14m

Ontario

Mon 1/5

1:04 pm-11:30 pm

1 stop8h 26m

$351

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Sat 12/13

7:20 am-12:34 pm

1 stop7h 14m

Ontario

Sat 1/10

1:10 pm-9:32 pm

1 stop6h 22m

$367

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Fri 11/14

8:04 pm-11:50 pm

1 stop5h 46m

$117

MilwaukeeOntario

MKE - ONT

MKEONT

Milwaukee-Mitchell

Fri 11/7

8:04 pm-11:10 am

1 stop17h 06m

$127

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/27

Showing 1-10 of 19 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 October.
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 December is currently the most expensive (average of $151). 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 October 29, 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 October 29, 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
8.0
Very good
4,241 reviews

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Overall

8.0

Crew

8.6

Food

7.0

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
8.0
Very good
4,241 reviews
Southwest
8.0
Very good
4,241 reviews

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Overall

8.0

Crew

8.6

Food

7.0

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
7,992 reviews
Southwest
8.0
Very good
4,241 reviews

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Overall

8.0

Crew

8.6

Food

7.0

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
8,999 reviews
Southwest
8.0
Very good
4,241 reviews

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Overall

8.0

Crew

8.6

Food

7.0

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
11,032 reviews
Southwest
8.0
Very good
4,241 reviews

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Overall

8.0

Crew

8.6

Food

7.0

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 $320, Delta can have you in Ontario from Milwaukee in 7h 53m. There are 1707 mi between Milwaukee and Ontario.

  • 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 35% lower than the current average price of a flight leaving 3 months from now.

  • 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 December is currently the most expensive (average of $151). 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

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Milwaukee to Ontario

See prices for flight routes from nearby airports that may be better suited for you.
O'Hare Intl to Las Vegas flights
Minneapolis to Las Vegas flights
O'Hare Intl to Los Angeles flights
O'Hare Intl to San Francisco flights
O'Hare Intl to Ontario flights
Minneapolis to Los Angeles flights
O'Hare Intl to Santa Ana flights
O'Hare Intl to San Diego flights
Minneapolis to San Francisco flights
Minneapolis to San Diego flights
O'Hare Intl to Palm Springs flights
Milwaukee to Las Vegas flights
O'Hare Intl to Burbank flights
Minneapolis to Ontario flights
O'Hare Intl to Sacramento flights
Madison to Las Vegas flights
O'Hare Intl to San Jose flights
Minneapolis to Palm Springs flights
Minneapolis to Santa Ana flights
O'Hare Intl to Reno flights
Appleton to Las Vegas flights
O'Hare Intl to Oakland flights
Milwaukee to Los Angeles flights
Minneapolis to Sacramento flights
Milwaukee to San Diego flights
Madison to San Francisco flights
Minneapolis to Oakland flights
Minneapolis to Reno flights
Minneapolis to San Jose flights
O'Hare Intl to Santa Barbara flights
Madison to San Diego flights
Madison to Los Angeles flights
Milwaukee to San Francisco flights
Minneapolis to Burbank flights
Green Bay to Las Vegas flights
Appleton to Los Angeles flights
Madison to Ontario flights
Appleton to San Diego flights
Milwaukee to Palm Springs flights
Milwaukee to Santa Ana flights
O'Hare Intl to Long Beach flights
Milwaukee to San Jose flights
O'Hare Intl to Fresno flights
Minneapolis to Fresno flights
Madison to San Jose flights
Milwaukee to Reno flights
Wausau to Las Vegas flights
Milwaukee to Burbank flights
Madison to Santa Ana flights

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 October 29, 2025.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$278Average$379FlexibilityNo cancel feeOn-time71%
DeltaCheapest$326Average$411FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$342Average$418FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$344Average$506FlexibilityNo cancel feeOn-time69%

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.