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Ontario

$1,332+ Cheap flights from Guam to Ontario (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 6/30. Fares are subject to change and may not be available on all flights or dates of travel.
GUM — ONT
Jun 17 — Jun 241
Tue 6/17
Tue 6/24
1 adult, Economy
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Cheap flight deals from Guam to Ontario

Keep the following information in mind while searching for Guam to Ontario flight deals. Data was last updated June 12, 2025.

Round-trip from

$1,578
(United Airlines)

One-way from

$1,332
(Delta)

Popular in

July

Cheapest in

October

Average price

$1,652
From Guam to Ontario
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One-way flight from Guam to Ontario
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Highest demand for flights based on searches. 8% potential increase in price ($138 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($17 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 Guam to Ontario

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

This United Airlines deal was found by Cheapflights users on 6/12. 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 8/207:15 amGUM - ONT
2 stops30h 18mUnited Airlines
Wed 9/36:50 pmONT - GUM
2 stops30h 15mUnited Airlines
Deal found 6/12$1,578

Cheapflights Fare Finder

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

Fly from

Guam

Fly to

Ontario

Route

Depart

Return

Price

TamuningOntario

GUM - ONT

GUMONT

Tamuning Guam Intl

Wed 8/20

7:15 am-8:33 pm

2 stops30h 18m

Ontario

Wed 9/3

6:50 pm-6:05 pm

2 stops30h 15m

$1,578

TamuningOntario

GUM - ONT

GUMONT

Tamuning Guam Intl

Mon 6/30

1:55 am-10:25 am

2 stops49h 30m

$1,332

TamuningOntario

GUM - ONT

GUMONT

Tamuning Guam Intl

Tue 7/1

7:15 am-5:25 pm

2 stops27h 10m

$1,390

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/9

Best time to book a flight from Guam to Ontario

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

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

Currently, August is the cheapest month in which you can book a flight from Guam to Ontario (average of $246). Flying from Guam 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.
Delta
8.0
Very good
7,950 reviews

Boarding

8.2

Comfort

7.9

Food

7.3

Overall

8.0

Entertainment

7.9

Crew

8.5

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

Boarding

8.2

Comfort

7.9

Food

7.3

Overall

8.0

Entertainment

7.9

Crew

8.5

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

Boarding

8.2

Comfort

7.9

Food

7.3

Overall

8.0

Entertainment

7.9

Crew

8.5

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 Guam to Ontario. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly into for flights to Ontario from Guam?

    For a flight from Guam to Ontario, you will be flying into Ontario. Ontario (ONT) is just 3.1 mi from the center of the city.

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

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

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

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

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

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

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

Discover the top airline that operate flights from Guam 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
United AirlinesCheapest$1,392Average$1,648FlexibilityNo cancel feeOn-time69%

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