$340+ 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 10/15. Fares are subject to change and may not be available on all flights or dates of travel.
GRB — ONT
Oct 4 — Oct 111
Round-trip
1 adult, Economy
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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
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Best
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Cheapest flights from Green Bay to OntarioExplore 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 September 4, 2026.
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 September 4, 2026.
This American Airlines deal was found by Cheapflights users on 8/31. 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 10/18:27 pm -
2 stops17h 39m
Mon 10/57:34 pm -
2 stops11h 48m
Deal found 8/31![American Airlines logo]()
$457
This United Airlines deal was found by Cheapflights users on 9/1. 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 11/141:58 pm -
1 stop6h 49m
Tue 11/177:00 am -
1 stop7h 52m
Deal found 9/1![United Airlines logo]()
$459
This American Airlines deal was found by Cheapflights users on 9/1. 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.
Wed 10/212:46 pm -
2 stops10h 07m
Wed 10/284:29 pm -
2 stops14h 53m
Deal found 9/1![American Airlines logo]()
$462
This United Airlines deal was found by Cheapflights users on 8/31. 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 9/113:42 pm -
1 stop9h 17m
Sun 9/137:13 pm -
2 stops12h 35m
Deal found 8/31![United Airlines logo]()
$471
This American Airlines deal was found by Cheapflights users on 9/2. 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 10/310:05 am -
2 stops10h 12m
Sat 10/104:29 pm -
2 stops14h 53m
Deal found 9/2![American Airlines logo]()
$478
This United Airlines deal was found by Cheapflights users on 9/2. 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 9/103:42 pm -
1 stop9h 17m
Wed 9/169:01 am -
2 stops12h 18m
Deal found 9/2![United Airlines logo]()
$526
This Delta deal was found by Cheapflights users on 8/31. 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 9/115:30 am -
1 stop7h 35m
Sun 9/1312:17 pm -
1 stop8h 07m
Deal found 8/31![Delta logo]()
$575
This Delta deal was found by Cheapflights users on 9/3. 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.
Tue 9/295:30 am -
1 stop7h 35m
Mon 10/1212:16 pm -
1 stop8h 11m
Deal found 9/3![Delta logo]()
$579
Best flights from Green Bay to OntarioDiscover carefully curated flight deals from Green Bay to Ontario that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 4, 2026.
Discover carefully curated flight deals from Green Bay to Ontario that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 4, 2026.
This United Airlines deal was found by Cheapflights users on 8/31. 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 11/1410:37 am -
2 stops11h 38m
Tue 11/177:00 am -
1 stop7h 52m
Deal found 8/31![United Airlines logo]()
$464
This United Airlines deal was found by Cheapflights users on 9/3. 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.
Mon 9/143:42 pm -
1 stop9h 17m
Tue 9/226:00 am -
2 stops9h 19m
Deal found 9/3![United Airlines logo]()
$693
This United Airlines deal was found by Cheapflights users on 8/30. 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 12/1910:47 am -
1 stop13h 51m
Sat 1/96:00 am -
2 stops13h 13m
Deal found 8/30![United Airlines logo]()
$701
This United Airlines deal was found by Cheapflights users on 9/1. 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 12/243:26 pm -
1 stop9h 15m
Tue 12/295:00 am -
2 stops16h 15m
Deal found 9/1![United Airlines logo]()
$707
Last-minute flights from Green Bay to OntarioDiscover last-minute flight deals from Green Bay to Ontario. Data last updated September 4, 2026 and is based on user searches.
Discover last-minute flight deals from Green Bay to Ontario. Data last updated September 4, 2026 and is based on user searches.
This United Airlines deal was found by Cheapflights users on 9/2. 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 9/103:42 pm -
1 stop9h 17m
Wed 9/169:01 am -
2 stops12h 18m
Deal found 9/2![United Airlines logo]()
$526
This United Airlines deal was found by Cheapflights users on 8/31. 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 9/113:42 pm -
1 stop9h 17m
Sun 9/137:13 pm -
2 stops12h 35m
Deal found 8/31![United Airlines logo]()
$471
This Delta deal was found by Cheapflights users on 8/31. 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 9/115:30 am -
1 stop7h 35m
Sun 9/1312:17 pm -
1 stop8h 07m
Deal found 8/31![Delta logo]()
$575
This Delta deal was found by Cheapflights users on 9/3. 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.
Tue 9/295:30 am -
1 stop7h 35m
Mon 10/1212:16 pm -
1 stop8h 11m
Deal found 9/3![Delta logo]()
$579
This American Airlines deal was found by Cheapflights users on 8/31. 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 10/18:27 pm -
2 stops17h 39m
Mon 10/57:34 pm -
2 stops11h 48m
Deal found 8/31![American Airlines logo]()
$457
This American Airlines deal was found by Cheapflights users on 9/2. 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 10/310:05 am -
2 stops10h 12m
Sat 10/104:29 pm -
2 stops14h 53m
Deal found 9/2![American Airlines logo]()
$478
This Delta deal was found by Cheapflights users on 9/2. 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 10/36:15 am -
2 stops7h 59m
Sat 10/1012:16 pm -
1 stop8h 01m
Deal found 9/2![Delta logo]()
$581
This United Airlines deal was found by Cheapflights users on 9/2. 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 10/161:17 pm -
2 stops11h 34m
Mon 10/191:24 pm -
2 stops7h 55m
Deal found 9/2![United Airlines logo]()
$600
This American Airlines deal was found by Cheapflights users on 9/1. 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.
Wed 10/212:46 pm -
2 stops10h 07m
Wed 10/284:29 pm -
2 stops14h 53m
Deal found 9/1![American Airlines logo]()
$462
One-way flights from Green Bay to OntarioSearch for one-way flight options from Green Bay to Ontario. Find affordable one-way fares based on user searches. Data last updated September 4, 2026.
Search for one-way flight options from Green Bay to Ontario. Find affordable one-way fares based on user searches. Data last updated September 4, 2026.
This Delta deal was found by Cheapflights users on 9/1. 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 10/155:30 am -
1 stop7h 36m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/1![Delta logo]()
$340
This American Airlines deal was found by Cheapflights users on 9/1. 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.
Mon 10/128:04 pm -
2 stops15h 06m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/1![American Airlines logo]()
$358
This Delta deal was found by Cheapflights users on 9/3. 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 9/231:10 pm -
1 stop9h 14m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/3![Delta logo]()
$374
This United Airlines deal was found by Cheapflights users on 9/3. 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.
Tue 9/153:42 pm -
1 stop9h 17m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/3![United Airlines logo]()
$379
This United Airlines deal was found by Cheapflights users on 9/2. 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 12/173:26 pm -
1 stop9h 12m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/2![United Airlines logo]()
$433
This United Airlines deal was found by Cheapflights users on 8/31. 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.
Sun 10/115:00 am -
2 stops12h 22m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 8/31![United Airlines logo]()
$438
This United Airlines deal was found by Cheapflights users on 9/2. 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 9/173:42 pm -
1 stop9h 17m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/2![United Airlines logo]()
$459
This United Airlines deal was found by Cheapflights users on 9/1. 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.
Mon 9/143:42 pm -
1 stop9h 17m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/1![United Airlines logo]()
$461
This United Airlines deal was found by Cheapflights users on 9/1. 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 9/265:00 am -
1 stop19h 49m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/1![United Airlines logo]()
$493
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 September 4, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $457 (American Airlines) |
One-way from | $340 (Delta) |
Popular in | March |
Cheapest in | December |
Average price | $470 |
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 7,457,451 searches. Data last updated September 4, 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
Cheapest round-trip
Quickest round-trip
Green BayOntario
GRB Green Bay Austin-Straubel - ONT Ontario
GRBONT
Green Bay Austin-Straubel
Thu 10/15
5:30 am-11:06 am
1 stop7h 36m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$340
Green BayOntario
GRB Green Bay Austin-Straubel - ONT Ontario
GRBONT
Green Bay Austin-Straubel
Tue 9/15
3:42 pm-10:59 pm
1 stop9h 17m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$379
Green BayOntario
GRB Green Bay Austin-Straubel - ONT Ontario
GRBONT
Green Bay Austin-Straubel
Sat 9/26
5:00 am-3:22 pm
2 stops12h 22m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$384
Green BayOntario
GRB Green Bay Austin-Straubel - ONT Ontario
GRBONT
Green Bay Austin-Straubel
Thu 10/15
1:17 pm-10:51 pm
2 stops11h 34m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$384
Green BayOntario
GRB Green Bay Austin-Straubel - ONT Ontario
GRBONT
Green Bay Austin-Straubel
Thu 12/17
3:26 pm-10:38 pm
1 stop9h 12m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$433
Green BayOntario
GRB Green Bay Austin-Straubel - ONT Ontario
GRBONT
Green Bay Austin-Straubel
Sun 10/11
5:00 am-3:22 pm
2 stops12h 22m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$438
Green BayOntario
GRB Green Bay Austin-Straubel - ONT Ontario
GRBONT
Green Bay Austin-Straubel
Thu 9/17
3:42 pm-10:59 pm
1 stop9h 17m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$459
Green BayOntario
GRB Green Bay Austin-Straubel - ONT Ontario
GRBONT
Green Bay Austin-Straubel
Sat 11/14
10:37 am-8:15 pm
2 stops11h 38m
Ontario
Tue 11/17
7:00 am-4:52 pm
1 stop7h 52m
$464
Green BayOntario
GRB Green Bay Austin-Straubel - ONT Ontario
GRBONT
Green Bay Austin-Straubel
Mon 9/14
9:03 am-9:59 pm
2 stops14h 56m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$466
Green BayOntario
GRB Green Bay Austin-Straubel - ONT Ontario
GRBONT
Green Bay Austin-Straubel
Mon 9/14
3:42 pm-10:59 pm
1 stop9h 17m
Ontario
Tue 9/22
6:00 am-5:19 pm
2 stops9h 19m
$693
Showing 1-10 of 12 resultsSorted by cheapest first
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 September.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars |
- 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.
GRB-ONT
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.
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 September 4, 2026.
Get a feel of what it's like to fly with Delta and 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.
Comfort
7.8
Entertainment
7.8
Food
7.2
Crew
8.5
Boarding
8.1
Overall
7.8
Reviews
1 / 20
10.0
ExcellentAaron,Oct 2024
TUS - LAX
Comfort
7.8
Entertainment
7.8
Food
7.2
Crew
8.5
Boarding
8.1
Overall
7.8
Reviews
1 / 20
10.0
ExcellentAaron,Oct 2024
TUS - LAX
Comfort
7.8
Entertainment
7.8
Food
7.2
Crew
8.5
Boarding
8.1
Overall
7.8
Reviews
1 / 20
10.0
ExcellentAaron,Oct 2024
TUS - LAX
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.
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Complete your trip
Complete your trip to Ontario by adding a car rental and/or hotel reservation to your travel itinerary.
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Other flights to Ontario
Explore flights to Ontario departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on September 4, 2026.
Green Bay and Ontario flights
Browse other Green Bay and Ontario flight options. Last updated on September 4, 2026.
Other flights from Green Bay
Browse through other flights departing from Green Bay. Flights are based on user searches made on Cheapflights and were last updated on September 4, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Top 2 airlines flying from Green Bay to Ontario
Discover the top 2 airlines 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 7,457,451 searches. Data last updated September 4, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$288 | Average$380 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$360 | Average$479 | FlexibilityNo cancel fee | On-timeN/A |