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Ontario

$258+ 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 5/26. Fares are subject to change and may not be available on all flights or dates of travel.
GRB — ONT
Jun 6 — Jun 131
Sat 6/6
Sat 6/13
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 May 7, 2026.

This Delta deal was found by Cheapflights users on 5/5. 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.
Fri 8/215:24 am
GRB
-
ONT
1 stop7h 18m
Delta
Thu 8/2710:00 pm
ONT
-
GRB
2 stops11h 22m
Delta
Deal found 5/5$354
This Delta deal was found by Cheapflights users on 5/5. 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 10/110:50 am
GRB
-
ONT
2 stops9h 11m
Delta
Mon 10/510:59 pm
ONT
-
GRB
2 stops9h 24m
Delta
Deal found 5/5$420
This United Airlines deal was found by Cheapflights users on 5/6. 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.
Sat 10/172:30 pm
GRB
-
ONT
1 stop9h 56m
United Airlines
Sat 10/247:00 am
ONT
-
GRB
1 stop6h 18m
United Airlines
Deal found 5/6$435
This United Airlines deal was found by Cheapflights users on 5/5. 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 9/210:34 am
GRB
-
ONT
2 stops11h 30m
United Airlines
Sat 9/57:13 pm
ONT
-
GRB
2 stops12h 46m
United Airlines
Deal found 5/5$445
This United Airlines deal was found by Cheapflights users on 5/5. 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 5/205:00 am
GRB
-
ONT
2 stops9h 38m
United Airlines
Sun 5/246:30 am
ONT
-
GRB
1 stop8h 21m
United Airlines
Deal found 5/5$476
This American Airlines deal was found by Cheapflights users on 5/6. 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.
Sat 8/153:47 pm
GRB
-
ONT
2 stops9h 11m
American Airlines
Mon 8/1711:59 pm
ONT
-
GRB
2 stops9h 58m
American Airlines
Deal found 5/6$535

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 May 7, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$354
(Delta)

One-way from

$258
(United Airlines)

Popular in

February

Cheapest in

May

Average price

$285
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
One-way flight from Green Bay Austin-Straubel to Ontario
Search Deals
Highest demand for flights based on searches. 21% potential increase in price ($101 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($12 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in May 2026
Search Deals

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 May 7, 2026.
Use the filters below to find and compare flights from Green Bay to Ontario that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Fri 8/21

5:24 am-10:42 am

1 stop7h 18m

Ontario

Thu 8/27

10:00 pm-11:22 am

2 stops11h 22m

$354

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Sat 10/17

1:11 pm-10:59 pm

2 stops11h 48m

Ontario

Sat 10/24

6:00 am-7:05 pm

2 stops11h 05m

$517

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Wed 9/2

10:34 am-6:19 pm

1 stop9h 45m

Ontario

Sat 9/5

7:13 pm-9:59 am

2 stops12h 46m

$552
Quickest round-trip

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Wed 7/8

6:15 am-12:10 pm

2 stops7h 55m

Ontario

Sat 7/11

12:00 pm-10:48 pm

1 stop8h 48m

$562

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Tue 8/18

10:34 am-8:52 pm

2 stops12h 18m

Ontario

Sat 8/22

5:45 am-9:15 pm

2 stops13h 30m

$601
Cheapest one-way

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Thu 5/28

5:20 am-10:57 am

1 stop7h 37m

$260

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Sat 5/30

5:20 am-4:17 pm

2 stops12h 57m

$269

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Sun 5/24

11:53 am-9:48 pm

2 stops11h 55m

$304
Quickest one-way

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Wed 5/27

5:26 pm-10:51 pm

1 stop7h 25m

$308

Green BayOntario

GRB - ONT

GRBONT

Green Bay Austin-Straubel

Fri 7/17

5:10 am-10:38 am

1 stop7h 28m

$309

Flights are sorted by cheapest round-trip flights first.

Deals found on 5/5

Showing 1-10 of 11 resultsSorted by cheapest first
1
2

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 May.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice 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 FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Green Bay-Ontario flight deals on Cheapflights vs. FlightHub >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 FlightHub the most. FlightHub 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

How much does it cost to fly round-trip from Green Bay to Ontario?

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 May 7, 2026.
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
9,690 reviews

Food

6.6

Crew

8.1

Comfort

7.3

Overall

7.4

Entertainment

7.1

Boarding

7.7

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
9,690 reviews
United Airlines
7.4
Good
9,690 reviews

Food

6.6

Crew

8.1

Comfort

7.3

Overall

7.4

Entertainment

7.1

Boarding

7.7

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 $354, Delta can have you in Ontario from Green Bay in 7h 18m. 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 23% 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.

See more FAQs

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Alternative routes for Green Bay to Ontario

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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 May 7, 2026.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$288Average$380FlexibilityNo cancel feeOn-time69%

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