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$404+ Cheap flights from Green Bay to Ontario (GRB - ONT)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 4/20. Fares are subject to change and may not be available on all flights or dates of travel.
GRB — ONT
Jan 15 — Jan 221
Thu 1/15
Thu 1/22
1 adult, Economy
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Cheap 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 December 16, 2025.

This United Airlines deal was found by Cheapflights users on 12/15. 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.
Fri 12/195:22 pmGRB - ONT
1 stop7h 03mUnited Airlines
Sun 12/2111:59 pmONT - GRB
1 stop8h 10mUnited Airlines
Deal found 12/15$639
This United Airlines deal was found by Cheapflights users on 12/15. 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.
Wed 12/318:00 amGRB - ONT
1 stop16h 25mUnited Airlines
Sun 1/46:39 pmONT - GRB
2 stops13h 30mUnited Airlines
Deal found 12/15$987

Find 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 December 16, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$319
(American Airlines)

Popular in

March

Cheapest in

May

Average price

$288
Provider with most accurate pricing for Green Bay Austin-Straubel-Ontario flight deals.
Search Deals
Provider most trusted by Cheapflights users for Green Bay Austin-Straubel-Ontario flights.
Search Deals
From Green Bay Austin-Straubel to Ontario
Search Deals
Highest demand for flights based on searches. 35% potential increase in price ($236 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 9% potential price decrease ($39 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 2025
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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 December 16, 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

Mon 4/20

2:45 pm-10:26 pm

1 stop9h 41m

Ontario

Mon 4/27

6:53 pm-9:45 am

2 stops12h 52m

$404

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Tue 1/27

2:39 pm-10:53 pm

2 stops10h 14m

Ontario

Sat 1/31

6:00 am-4:47 pm

2 stops8h 47m

$409

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Wed 1/14

2:39 pm-10:53 pm

2 stops10h 14m

Ontario

Wed 1/21

6:00 am-7:03 pm

2 stops11h 03m

$409

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Thu 2/19

5:12 am-12:02 pm

1 stop8h 50m

Ontario

Mon 2/23

10:20 pm-11:24 am

2 stops11h 04m

$449

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Tue 1/13

2:39 pm-10:53 pm

2 stops10h 14m

Ontario

Tue 1/20

6:00 am-9:31 pm

2 stops13h 31m

$479

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Tue 1/6

10:42 am-9:59 pm

2 stops13h 17m

Ontario

Tue 1/13

6:32 pm-10:07 am

2 stops13h 35m

$479

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Fri 1/2

10:44 am-9:07 pm

2 stops12h 23m

Ontario

Sun 1/4

6:39 pm-10:09 am

2 stops13h 30m

$617

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/15

Compare providers for flights from Green Bay 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 Green Bay 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 Green Bay-Ontario flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Green Bay-Ontario flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Green Bay-Ontario flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Green Bay-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 Green Bay-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 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, July is the cheapest month in which you can book a flight from Green Bay to Ontario (average of $60). Flying from Green Bay to Ontario in March is currently the most expensive (average of $287). 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.

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 December 16, 2025.
Get a feel of what it's like to fly with United Airlines from Green Bay to Ontario by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
9,095 reviews

Entertainment

7.1

Crew

8.1

Overall

7.4

Food

6.6

Boarding

7.7

Comfort

7.3

Reviews

1 / 20
10.0
Excellent

Anonymous,Sep 2025

FRA - SFO

Lufthansa was amazing, I wish United States based airlines operated like them.
United Airlines
7.4
Good
9,095 reviews
United Airlines
7.4
Good
9,095 reviews

Entertainment

7.1

Crew

8.1

Overall

7.4

Food

6.6

Boarding

7.7

Comfort

7.3

Reviews

1 / 20
10.0
Excellent

Anonymous,Sep 2025

FRA - SFO

Lufthansa was amazing, I wish United States based airlines operated like them.

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.

  • How long is the flight from Green Bay to Ontario?

    For as low as $449, United Airlines can have you in Ontario from Green Bay in 8h 50m. There are 1720 mi between Green Bay and Ontario. This flight may include one or multiple stops.

  • What is the cheapest airline to fly from Green Bay to Ontario round-trip?

    Currently priced at $288, United Airlines will fly you from Green Bay to Ontario and back. In addition to United Airlines, many other airlines offer competitively priced options for your trip. This flight start at 32% lower than the current average price 3 months from now.

  • 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, July is the cheapest month in which you can book a flight from Green Bay to Ontario (average of $60). Flying from Green Bay to Ontario in March is currently the most expensive (average of $287). 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.

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Top airline flying from Green Bay to Ontario

Discover the top airline that operate flights from Green Bay 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 December 16, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$288Average$338FlexibilityNo cancel feeOn-time69%

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