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$149+ Cheap flights from Greenville to Ontario (GSP - 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 9/4. Fares are subject to change and may not be available on all flights or dates of travel.
GSP — ONT
Jun 17 — Jun 241
Tue 6/17
Tue 6/24
1 adult, Economy
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Cheap flight deals from Greenville to Ontario

Discover tips and strategies to find the most affordable flight options for your journey from Greenville (GSP) 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

$339
(Delta)

One-way from

$149
(Delta)

Popular in

November

Cheapest in

February

Average price

$533
From Greenville to Ontario
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One-way flight from Greenville to Ontario
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Highest demand for flights based on searches. 16% potential increase in price ($96 potential increase over avg. RT price).
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Cheapest flight prices on average. 4% potential price decrease ($22 potential savings vs. average RT price).
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Average for round-trip flights in June 2025
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Find flight deals from Greenville to Ontario

Cheapest flights from Greenville to Ontario
Explore the most affordable flight options available from Greenville to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 12, 2025.

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 9/46:30 amGSP - ONT
1 stop7h 05mDelta
Sun 9/1410:59 pmONT - GSP
1 stop7h 26mDelta
Deal found 6/10$339
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.
Wed 8/135:43 pmGSP - ONT
1 stop8h 05mAmerican Airlines
Sun 8/1711:59 pmONT - GSP
2 stops8h 54mAmerican Airlines
Deal found 6/10$344
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.
Fri 8/154:25 pmGSP - ONT
1 stop7h 29mUnited Airlines
Sat 8/236:04 amONT - GSP
1 stop6h 42mUnited Airlines
Deal found 6/10$357
This Alaska 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/97:15 amGSP - ONT
2 stops14h 13mAlaska Airlines
Tue 9/166:00 amONT - GSP
2 stops13h 30mAlaska Airlines
Deal found 6/10$502

Cheapflights Fare Finder

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

Fly from

Greenville

Fly to

Ontario

Route

Depart

Return

Price

GreenvilleOntario

GSP - ONT

GSPONT

Greenville

Thu 9/4

6:30 am-10:35 am

1 stop7h 05m

Ontario

Sun 9/14

10:59 pm-9:25 am

1 stop7h 26m

$339

GreenvilleOntario

GSP - ONT

GSPONT

Greenville

Wed 8/13

5:43 pm-10:48 pm

1 stop8h 05m

Ontario

Sun 8/17

11:59 pm-11:53 am

2 stops8h 54m

$344

GreenvilleOntario

GSP - ONT

GSPONT

Greenville

Fri 8/15

4:25 pm-8:54 pm

1 stop7h 29m

Ontario

Sat 8/23

6:04 am-3:46 pm

1 stop6h 42m

$357

GreenvilleOntario

GSP - ONT

GSPONT

Greenville

Tue 9/9

7:15 am-6:28 pm

2 stops14h 13m

Ontario

Tue 9/16

6:00 am-10:30 pm

2 stops13h 30m

$502

GreenvilleOntario

GSP - ONT

GSPONT

Greenville

Thu 9/4

6:30 am-10:35 am

1 stop7h 05m

$149

GreenvilleOntario

GSP - ONT

GSPONT

Greenville

Wed 12/3

7:06 am-1:43 pm

2 stops9h 37m

$154

GreenvilleOntario

GSP - ONT

GSPONT

Greenville

Thu 9/4

9:35 am-8:33 pm

2 stops13h 58m

$204

GreenvilleOntario

GSP - ONT

GSPONT

Greenville

Thu 7/10

5:45 am-2:45 pm

2 stops12h 00m

$249

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/10

Best time to book a flight from Greenville to Ontario

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

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

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

What is the cheapest time of day to fly from GSP to ONT?

Find hourly flight availability from Greenville to Ontario. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated June 12, 2025.

It’s typically best to fly out from Greenville to Ontario in the evening. Doing so could potentially save you 29% on the flight price compared to flying at noon, which is usually more expensive.

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 Alaska Airlines, Southwest and Delta from Greenville to Ontario. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Crew

8.5

Overall

8.0

Comfort

7.8

Boarding

8.1

Food

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Alaska Airlines
8.0
Very good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Crew

8.5

Overall

8.0

Comfort

7.8

Boarding

8.1

Food

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Southwest
8.0
Very good
4,287 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Crew

8.5

Overall

8.0

Comfort

7.8

Boarding

8.1

Food

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Delta
8.0
Very good
7,950 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Crew

8.5

Overall

8.0

Comfort

7.8

Boarding

8.1

Food

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
United Airlines
7.4
Good
8,790 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Crew

8.5

Overall

8.0

Comfort

7.8

Boarding

8.1

Food

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
American Airlines
7.2
Good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Crew

8.5

Overall

8.0

Comfort

7.8

Boarding

8.1

Food

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Related info for your journey

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

    Our cheapest airline available from Greenville to Ontario is Delta. Our recent data shows that you can find tickets from as low as $339 on this airline. Additional options worth looking into are American Airlines and United Airlines, starting at $344 and $357 round-trip. Users have found that Delta is 30% cheaper than the other options available to this destination.

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

    The cheapest airline one-way is Delta, with whom users have recently found tickets for as low as $149. However, be on the lookout for offers from American Airlines and United Airlines, as they are both options that can get you from Greenville to Ontario for a low price.

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

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

  • How can I find direct flights from Greenville to Ontario?

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

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

    Yes. Cheapflights offers flight deals from Greenville 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 Greenville to Ontario?

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

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Top 2 airlines flying from Greenville to Ontario

Discover the top 2 airlines that operate flights from Greenville 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 June 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$312Average$476FlexibilityNo cancel feeOn-time71%
DeltaCheapest$328Average$512FlexibilityNo cancel feeOn-timeN/A

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