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$149+ Cheap flights from Portland, ME to Ontario (PWM - 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 9/5. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — ONT
Jul 8 — Jul 151
Tue 7/8
Tue 7/15
1 adult, Economy
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Cheap flight deals from Portland to Ontario

Discover tips and strategies to find the most affordable flight options for your journey from Portland (PWM) 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 July 3, 2025.

Round-trip from

$279
(American Airlines)

One-way from

$149
(Delta)

Popular in

December

Cheapest in

May

Average price

$547
From Portland to Ontario
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One-way flight from Portland to Ontario
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Highest demand for flights based on searches. 14% potential increase in price ($95 potential increase over avg. RT price).
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Cheapest flight prices on average. 6% potential price decrease ($34 potential savings vs. average RT price).
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Average for round-trip flights in July 2025
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Find flight deals from Portland to Ontario

Cheapest flights from Portland to Ontario
Explore the most affordable flight options available from Portland to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 3, 2025.

This American Airlines deal was found by Cheapflights users on 7/1. 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.
Thu 7/246:25 pmPWM - ONT
1 stop8h 29mAmerican Airlines
Tue 7/298:15 amONT - PWM
2 stops12h 04mAmerican Airlines
Deal found 7/1$279
This JetBlue deal was found by Cheapflights users on 7/2. 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 JetBlue is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/112:17 pmPWM - ONT
1 stop10h 12mJetBlue
Sun 9/1410:56 pmONT - PWM
1 stop11h 26mJetBlue
Deal found 7/2$291
This Delta deal was found by Cheapflights users on 7/2. 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.
Thu 9/181:35 pmPWM - ONT
1 stop8h 40mDelta
Mon 9/2210:00 pmONT - PWM
2 stops12h 00mDelta
Deal found 7/2$302
This United Airlines deal was found by Cheapflights users on 7/3. 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.
Fri 9/54:56 pmPWM - ONT
1 stop8h 34mUnited Airlines
Fri 9/126:38 pmONT - PWM
2 stops11h 46mUnited Airlines
Deal found 7/3$402

Cheapflights Fare Finder

Customize your flight search to find flights from Portland 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 July 3, 2025.
Use the filters below to find and compare flights from Portland to Ontario that are best for you.

Fly from

Portland

Fly to

Ontario

Route

Depart

Return

Price

PortlandOntario

PWM - ONT

PWMONT

Portland

Thu 7/24

6:25 pm-11:54 pm

1 stop8h 29m

Ontario

Tue 7/29

8:15 am-11:19 pm

2 stops12h 04m

$279

PortlandOntario

PWM - ONT

PWMONT

Portland

Thu 9/11

2:17 pm-9:29 pm

1 stop10h 12m

Ontario

Sun 9/14

10:56 pm-1:22 pm

1 stop11h 26m

$291

PortlandOntario

PWM - ONT

PWMONT

Portland

Thu 9/18

1:35 pm-7:15 pm

1 stop8h 40m

Ontario

Mon 9/22

10:00 pm-1:00 pm

2 stops12h 00m

$302

PortlandOntario

PWM - ONT

PWMONT

Portland

Fri 9/5

4:56 pm-10:30 pm

1 stop8h 34m

Ontario

Fri 9/12

6:38 pm-9:24 am

2 stops11h 46m

$402

PortlandOntario

PWM - ONT

PWMONT

Portland

Fri 9/5

1:34 pm-7:11 pm

1 stop8h 37m

$149

PortlandOntario

PWM - ONT

PWMONT

Portland

Wed 8/20

2:19 pm-9:59 pm

1 stop10h 40m

$156

PortlandOntario

PWM - ONT

PWMONT

Portland

Sat 8/30

5:02 pm-10:30 pm

1 stop8h 28m

$169

PortlandOntario

PWM - ONT

PWMONT

Portland

Mon 9/8

5:50 am-11:35 am

1 stop8h 45m

$197

PortlandOntario

PWM - ONT

PWMONT

Portland

Thu 9/4

2:02 pm-12:03 am

2 stops13h 01m

$204

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/3

Best time to book a flight from Portland to Ontario

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

What is the cheapest month to book a flight from Portland, Maine to Ontario?

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

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 July 3, 2025.
Read reviews from past customers who have flown Alaska Airlines, Southwest, and Delta from Portland to Ontario. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Crew

8.5

Entertainment

7.1

Boarding

8.1

Food

7.1

Comfort

7.8

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

Overall

8.0

Crew

8.5

Entertainment

7.1

Boarding

8.1

Food

7.1

Comfort

7.8

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
4,266 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Crew

8.5

Entertainment

7.1

Boarding

8.1

Food

7.1

Comfort

7.8

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
7,982 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Crew

8.5

Entertainment

7.1

Boarding

8.1

Food

7.1

Comfort

7.8

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
8,861 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Crew

8.5

Entertainment

7.1

Boarding

8.1

Food

7.1

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
JetBlue
7.3
Good
2,916 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Crew

8.5

Entertainment

7.1

Boarding

8.1

Food

7.1

Comfort

7.8

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 Portland 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 Portland, Maine to Ontario round-trip?

    American Airlines, at $279, was found to be the cheapest airline from Portland, Maine to Ontario.Alternate airlines to your destination round-trip include JetBlue and Delta. Users have found that American Airlines is 51% cheaper than the other options available to this destination.

  • What are the cheapest airlines to fly from Portland, Maine to Ontario one-way?

    The cheapest airlines for a one-way flight from Portland, Maine to Ontario are Delta ($149), JetBlue ($156), and United Airlines ($169).

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Portland 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 Portland, Maine to Ontario?

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

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Top 2 airlines flying from Portland to Ontario

Discover the top 2 airlines that operate flights from Portland 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 July 3, 2025.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$302Average$442FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$329Average$547FlexibilityNo cancel feeOn-time71%

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