HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Ontario

$149+ Cheap flights from Green Bay to Ontario (GRB - 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 6/27. Fares are subject to change and may not be available on all flights or dates of travel.
GRB — ONT
Jun 17 — Jun 241
Tue 6/17
Tue 6/24
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Green Bay 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.

Cheap flight deals from Green Bay to Ontario

Discover tips and strategies to find the most affordable flight options for your journey from Green Bay (GRB) 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

$300
(FlightHub)

One-way from

$149
(Frontier)

Popular in

October

Cheapest in

August

Average price

$339
From Green Bay Austin-Straubel to Ontario
Search Deals
One-way flight from Green Bay Austin-Straubel to Ontario
Search Deals
Highest demand for flights based on searches. 23% potential increase in price ($152 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 8% potential price decrease ($39 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in June 2025
Search Deals

Find flight deals from Green Bay to Ontario

Cheapest flights from Green Bay to Ontario
Explore the most affordable flight options available from Green Bay 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 6/11. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/157:52 pmGRB - ONT
1 stop5h 58mFrontier
Sun 8/175:21 pmONT - GRB
1 stop23h 34mFrontier
Deal found 6/11$300
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 8/215:31 amGRB - ONT
1 stop7h 04mDelta
Sun 8/2410:00 pmONT - GRB
2 stops10h 27mDelta
Deal found 6/10$344
This American 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/216:02 amGRB - ONT
2 stops12h 22mAmerican Airlines
Sun 8/2411:59 pmONT - GRB
2 stops12h 30mAmerican Airlines
Deal found 6/10$377
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.
Thu 8/215:30 pmGRB - ONT
1 stop7h 00mUnited Airlines
Sun 8/247:00 amONT - GRB
1 stop6h 09mUnited Airlines
Deal found 6/10$379

Cheapflights Fare Finder

Customize your flight search to find flights from Green Bay 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 Green Bay to Ontario that are best for you.

Fly from

Green Bay

Fly to

Ontario

Route

Depart

Return

Price

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Fri 8/15

7:52 pm-11:50 pm

1 stop5h 58m

Ontario

Sun 8/17

5:21 pm-6:55 pm

1 stop23h 34m

$300

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Thu 8/21

5:31 am-10:35 am

1 stop7h 04m

Ontario

Sun 8/24

10:00 pm-10:27 am

2 stops10h 27m

$344

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Thu 8/21

6:02 am-4:24 pm

2 stops12h 22m

Ontario

Sun 8/24

11:59 pm-2:29 pm

2 stops12h 30m

$377

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Thu 8/21

5:30 pm-10:30 pm

1 stop7h 00m

Ontario

Sun 8/24

7:00 am-3:09 pm

1 stop6h 09m

$379

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Fri 6/27

7:53 pm-11:50 pm

1 stop5h 57m

$149

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Sat 9/20

5:30 pm-10:30 pm

1 stop7h 00m

$220

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Tue 7/22

5:03 pm-11:42 pm

2 stops8h 39m

$235

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Tue 7/22

2:51 pm-9:38 pm

3 stops8h 47m

$577

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/12

Best time to book a flight from Green Bay to Ontario

Have a flexible travel schedule? Discover the best time to fly to Ontario from Green Bay 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 Green Bay to Ontario

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

Currently, August is the cheapest month in which you can book a flight from Green Bay to Ontario (average of $246). Flying from Green Bay 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.

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.
Read reviews from past customers who have flown Delta, United Airlines and American Airlines from Green Bay to Ontario. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,950 reviews

Food

7.3

Boarding

8.2

Crew

8.5

Entertainment

7.9

Comfort

7.9

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Delta
8.0
Very good
7,950 reviews
Delta
8.0
Very good
7,950 reviews

Food

7.3

Boarding

8.2

Crew

8.5

Entertainment

7.9

Comfort

7.9

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
United Airlines
7.4
Good
8,790 reviews
Delta
8.0
Very good
7,950 reviews

Food

7.3

Boarding

8.2

Crew

8.5

Entertainment

7.9

Comfort

7.9

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
American Airlines
7.2
Good
10,000 reviews
Delta
8.0
Very good
7,950 reviews

Food

7.3

Boarding

8.2

Crew

8.5

Entertainment

7.9

Comfort

7.9

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Frontier
5.9
Fair
3,295 reviews
Delta
8.0
Very good
7,950 reviews

Food

7.3

Boarding

8.2

Crew

8.5

Entertainment

7.9

Comfort

7.9

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Related info for your journey

Find useful and relevant information for your journey from Green Bay 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 Green Bay to Ontario round-trip?

    Currently priced at $300, Frontier will fly you from Green Bay to Ontario and back. In addition to Frontier, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from Delta and American Airlines - these airlines can fly you to your destination from $344 and $377, respectively. These flights start at 40% lower than the current average price 3 months from now.

  • What are the cheapest airlines to fly from Green Bay to Ontario one-way?

    One-way options have recently been found by users for as low as $149 on Frontier. Other airlines that offer cheap prices include United Airlines from $220 and Delta from $235 one-way.

  • Can I find deals for flights from Green Bay to Ontario that include hotel bookings?

    Yes. In addition to deals on Green Bay to Ontario flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Green Bay to Ontario?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Green Bay to Ontario.

  • Can I find deals for business class flights from Green Bay to Ontario?

    Yes. Cheapflights offers flight deals from Green Bay 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 Green Bay to Ontario?

    Currently, August is the cheapest month in which you can book a flight from Green Bay to Ontario (average of $246). Flying from Green Bay 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

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 Green Bay to Ontario

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

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.