What is the cheapest airline that flies from Ontario to Milwaukee-Mitchell?

United Airlines, Delta, and American Airlines are the most popular carriers operating from Ontario to Milwaukee-Mitchell

What airlines fly to Milwaukee?

American Airlines, United Airlines and Spirit Airlines are the top three most popular airlines that fly to Milwaukee from Ontario according to our data. American Airlines is the first choice among our users, with 42% of people opting to fly with this airline when traveling to Milwaukee. Keep in mind that there are 9 different airlines that fly to Milwaukee on a routine basis, so you have a few additional options to choose from.

When did momondo last update prices for flights from Ontario Airport to Milwaukee-Mitchell Airport?

Prices for flights from Ontario Airport to Milwaukee-Mitchell Airport are updated daily.

How many operators does momondo search for flights from Ontario Airport to Milwaukee-Mitchell Airport?

As of December 2025, there are 4 operators available to choose from for flights from Ontario Airport to Milwaukee-Mitchell Airport.

How old do you have to be to fly from Ontario Airport to Milwaukee-Mitchell Airport?

Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Ontario Airport to Milwaukee-Mitchell Airport.

What documentation or ID do you need to fly to Milwaukee-Mitchell Airport?

The travel and health documents required for your trip to Milwaukee-Mitchell Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Milwaukee-Mitchell Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

$151 Cheap Flights from Ontario to Milwaukee in 2025/26

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Find the cheapest flights from Ontario to Milwaukee

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Cheap round-trip flights

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11:53 am - 2:57 pm

ONT

MKE

25h 04m1 stop

3:53 pm - 3:08 pm

MKE

ONT

25h 15m1 stop

$304Alaska Airlines

Thu, Jan 22 - Mon, Jan 26

10:20 pm - 9:09 am

ONT

MKE

8h 49m1 stop

7:20 am - 12:07 pm

MKE

ONT

6h 47m1 stop

$331Delta

Wed, Feb 18 - Sat, Feb 21

7:30 am - 9:34 pm

ONT

MKE

12h 04m2 stops

11:14 am - 10:37 pm

MKE

ONT

13h 23m2 stops

$332Delta

Wed, Feb 18 - Sat, Feb 21

10:20 pm - 9:09 am

ONT

MKE

8h 49m1 stop

7:20 am - 12:07 pm

MKE

ONT

6h 47m1 stop

$334Delta

Wed, Feb 18 - Sat, Feb 21

1:24 pm - 9:21 pm

ONT

MKE

5h 57m1 stop

8:00 am - 12:47 pm

MKE

ONT

6h 47m1 stop

$336United Airlines

Sat, Jan 17 - Thu, Jan 22

1:24 pm - 9:21 pm

ONT

MKE

5h 57m1 stop

8:00 am - 5:43 pm

MKE

ONT

11h 43m2 stops

$341United Airlines

Sat, Jan 17 - Thu, Jan 22

7:30 am - 9:34 pm

ONT

MKE

12h 04m2 stops

7:20 am - 12:07 pm

MKE

ONT

6h 47m1 stop

$343Delta

Wed, Feb 18 - Sat, Feb 21

5:05 am - 3:43 pm

ONT

MKE

8h 38m2 stops

2:32 pm - 10:53 pm

MKE

ONT

10h 21m2 stops

$346United Airlines

Sat, Jan 17 - Thu, Jan 22

4:03 pm - 2:57 pm

ONT

MKE

20h 54m1 stop

3:53 pm - 11:56 pm

MKE

ONT

10h 03m1 stop

$363Alaska Airlines

Thu, Jan 15 - Thu, Jan 22

5:50 am - 2:15 pm

ONT

MKE

6h 25m1 stop

6:20 pm - 10:45 pm

MKE

ONT

6h 25m1 stop

$369Southwest

Thu, Feb 19 - Sat, Feb 21

Alaska Airlines flights from Ontario to Milwaukee

Our best Alaska Airlines deals on Ontario to Milwaukee flight tickets

Alaska Airlines

Jan 22

ONT11:53 amOntario

25h 04m

1 stop

MKE2:57 pmMilwaukee-Mitchell

Jan 26

MKE3:53 pmMilwaukee-Mitchell

25h 15m

1 stop

ONT3:08 pmOntario

$304

Find similar

Alaska Airlines

Jan 15

ONT4:03 pmOntario

20h 54m

1 stop

MKE2:57 pmMilwaukee-Mitchell

Jan 22

MKE3:53 pmMilwaukee-Mitchell

10h 03m

1 stop

ONT11:56 pmOntario

$363

Find similar

Alaska Airlines

Jan 18

ONT4:03 pmOntario

20h 54m

1 stop

MKE2:57 pmMilwaukee-Mitchell

Jan 22

MKE3:53 pmMilwaukee-Mitchell

10h 03m

1 stop

ONT11:56 pmOntario

$375

Find similar

United Airlines flights from Ontario to Milwaukee

Our best United Airlines deals on Ontario to Milwaukee flight tickets

United Airlines

Jan 17

ONT1:24 pmOntario

5h 57m

1 stop

MKE9:21 pmMilwaukee-Mitchell

Jan 22

MKE8:00 amMilwaukee-Mitchell

11h 43m

2 stops

ONT5:43 pmOntario

$341

Find similar

United Airlines

Jan 17

ONT5:05 amOntario

8h 38m

2 stops

MKE3:43 pmMilwaukee-Mitchell

Jan 22

MKE2:32 pmMilwaukee-Mitchell

10h 21m

2 stops

ONT10:53 pmOntario

$346

Find similar

United Airlines

Jan 12

ONT6:39 pmOntario

13h 55m

2 stops

MKE10:34 amMilwaukee-Mitchell

Jan 19

MKE4:05 pmMilwaukee-Mitchell

6h 53m

1 stop

ONT8:58 pmOntario

$376

Find similar

Fly from

Fly to

Route

Depart

Return

Price

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Thu 1/22

11:53 am-2:57 pm

1 stop25h 04m

Milwaukee-Mitchell

Mon 1/26

3:53 pm-3:08 pm

1 stop25h 15m

$304

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Wed 2/18

10:20 pm-9:09 am

1 stop8h 49m

Milwaukee-Mitchell

Sat 2/21

7:20 am-12:07 pm

1 stop6h 47m

$331

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Wed 2/18

7:30 am-9:34 pm

2 stops12h 04m

Milwaukee-Mitchell

Sat 2/21

11:14 am-10:37 pm

2 stops13h 23m

$332

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Wed 2/18

10:20 pm-9:09 am

1 stop8h 49m

Milwaukee-Mitchell

Sat 2/21

7:20 am-12:07 pm

1 stop6h 47m

$334

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Sat 1/17

1:24 pm-9:21 pm

1 stop5h 57m

Milwaukee-Mitchell

Thu 1/22

8:00 am-12:47 pm

1 stop6h 47m

$336

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Sat 1/17

1:24 pm-9:21 pm

1 stop5h 57m

Milwaukee-Mitchell

Thu 1/22

8:00 am-5:43 pm

2 stops11h 43m

$341

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Wed 2/18

7:30 am-9:34 pm

2 stops12h 04m

Milwaukee-Mitchell

Sat 2/21

7:20 am-12:07 pm

1 stop6h 47m

$343

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Sat 1/17

5:05 am-3:43 pm

2 stops8h 38m

Milwaukee-Mitchell

Thu 1/22

2:32 pm-10:53 pm

2 stops10h 21m

$346

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Thu 1/15

4:03 pm-2:57 pm

1 stop20h 54m

Milwaukee-Mitchell

Thu 1/22

3:53 pm-11:56 pm

1 stop10h 03m

$363

OntarioMilwaukee

ONT - MKE

ONTMKE

Ontario

Thu 2/19

5:50 am-2:15 pm

1 stop6h 25m

Milwaukee-Mitchell

Sat 2/21

6:20 pm-10:45 pm

1 stop6h 25m

$369

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

How to get the cheapest flight ticket from Ontario to Milwaukee

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

Prices

Airlines

What is the cheapest month to fly to Milwaukee?

The cheapest month to fly to Milwaukee from Ontario is in September. Flight prices, which tend to average around $366, are often lower during this time because this is during the off-season. The month of May is another great option to travel to Milwaukee, with average flight prices from Ontario averaging around $375.

What is the cheapest day to depart on your flight to Milwaukee?

According to our data, Thursday is the cheapest day to fly to Milwaukee from Ontario. The lowest ticket price found for a Thursday departure recently was $181. Keep in mind that prices can always vary depending on your route and whether or not you are flying domestic or international. Flights from Ontario to Milwaukee on a Saturday will generally be more expensive and average around $408. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.

What is the cheapest time of day to depart on your flight to Milwaukee?

In the morning is the cheapest time of day to fly from Ontario to Milwaukee when you can find flight prices for as low as $180. Flying to Milwaukee in the morning is an ideal time because this is during off-peak travel hours. In the afternoon is when there is more demand to fly to Milwaukee, so prices are often more expensive at around $463 per ticket.

How have Ontario to Milwaukee flight prices changed over time?

As of December 2025, prices for Ontario to Milwaukee flights are approximately 124% more expensive when compared to flights at the same time last year.

When to book flights from Ontario to Milwaukee

Are you open to changing your travel dates? Check out the ideal times to fly from Ontario to Milwaukee according to our flight data. Find out which month and days have the cheapest flights.

Estimated round-trip price

Cheap Ontario to Milwaukee (ONT to MKE) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Ontario to Milwaukee

Fastest flight time	5h 31m
Direct flights	None

The fastest flight from Ontario to Milwaukee takes 5h 31m

There are no direct flights from Ontario to Milwaukee. There are no popular flight routes from Ontario to Milwaukee.

Search flight deals

How far is Ontario to Milwaukee-Mitchell by plane?
The straight-line distance from Ontario to Milwaukee-Mitchell is 1710.4 mi. Flights usually cover this in 5h 31m, depending on flying conditions and air traffic around both airports.
When did momondo last update prices for flights from Ontario Airport to Milwaukee-Mitchell Airport?
Prices for flights from Ontario Airport to Milwaukee-Mitchell Airport are updated daily.
How many operators does momondo search for flights from Ontario Airport to Milwaukee-Mitchell Airport?
As of December 2025, there are 4 operators available to choose from for flights from Ontario Airport to Milwaukee-Mitchell Airport.
How old do you have to be to fly from Ontario Airport to Milwaukee-Mitchell Airport?
Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Ontario Airport to Milwaukee-Mitchell Airport.
What documentation or ID do you need to fly to Milwaukee-Mitchell Airport?
The travel and health documents required for your trip to Milwaukee-Mitchell Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Milwaukee-Mitchell Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.
What is the most popular airline from Ontario to Milwaukee?
momondo data reveals that the most frequently booked airline on the route from Ontario to Milwaukee is Southwest, representing 55% of all bookings. The subsequent popular airlines are American Airlines at 28%, United Airlines at 12%, and Delta at 6%.

Best airlines flying from Ontario to Milwaukee

Compare and see reviews for airlines that fly from Ontario to Milwaukee with momondo

Airline	Rating	Free Cancellation	Price
Delta	PriceFrom $253	Free Cancellation	Rating 7.9 8,005 reviews	Search Delta flights
American Airlines	PriceFrom $276	Free Cancellation	Rating 7.2 11,054 reviews	Search American Airlines flights
United Airlines	PriceFrom $309	Free Cancellation	Rating 7.4 9,091 reviews	Search United Airlines flights
Southwest	PriceFrom $330	Free Cancellation	Rating 7.9 4,250 reviews	Search Southwest flights

Sheboygan

Waukesha

Wauwatosa

Oak Creek

Mequon

Glendale

Pewaukee

Kohler

Port Washington

West Bend

New Berlin

Grafton

Why use momondo?

Why should I use momondo to find a flight deal from Ontario to Milwaukee?

momondo collates all your flight options in one place and lets you filter them to find the perfect flight from Ontario to Milwaukee. momondo saves you time and could save you money on your trip.

Can I find flights from Ontario to Milwaukee with flexible booking policies on momondo?

Yes. momondo allows you to filter the results for Ontario to Milwaukee flights to just show those with flexible booking policies.

How can momondo help me find flights from Ontario to Milwaukee?

momondo provides multiple filters to help you find the best flight to Milwaukee from Ontario. Filter by price, airline, airports, cabin, aircraft, payment method, number of stops and more.

I’m not ready to book a flight from Ontario to Milwaukee right now. Can momondo alert me if prices change?

Price alerts on flights to Milwaukee from Ontario are quick and easy to set up on momondo. Simply perform a search and select the price alert feature. It is as simple as that.