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$131+ 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 10/28. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — ONT
Oct 17 — Oct 241
Fri 10/17
Fri 10/24
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 September 17, 2025.

Round-trip from

$302
(Delta)

One-way from

$131
(Southwest)

Popular in

December

Cheapest in

May

Average price

$350
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. 20% potential increase in price ($149 potential increase over avg. RT price).
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Cheapest flight prices on average. 7% potential price decrease ($41 potential savings vs. average RT price).
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Average for round-trip flights in September 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 September 17, 2025.

This Delta deal was found by Cheapflights users on 9/16. 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 11/11:27 pmPWM - ONT
1 stop8h 52mDelta
Mon 11/310:00 pmONT - PWM
2 stops12h 06mDelta
Deal found 9/16$302
This American Airlines deal was found by Cheapflights users on 9/16. 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 12/175:46 amPWM - ONT
2 stops11h 09mAmerican Airlines
Wed 1/78:43 amONT - PWM
2 stops12h 07mAmerican Airlines
Deal found 9/16$342
This Priceline deal was found by Cheapflights users on 9/15. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/302:17 pmPWM - ONT
1 stop10h 12mJetBlue
Sat 10/410:56 pmONT - PWM
1 stop11h 26mJetBlue
Deal found 9/15$353
This JetBlue deal was found by Cheapflights users on 9/16. 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 10/22:17 pmPWM - ONT
1 stop10h 12mJetBlue
Mon 10/610:56 pmONT - PWM
1 stop11h 26mJetBlue
Deal found 9/16$363
This United Airlines deal was found by Cheapflights users on 9/15. 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 11/124:54 pmPWM - ONT
1 stop8h 37mUnited Airlines
Mon 11/175:05 amONT - PWM
1 stop7h 43mUnited Airlines
Deal found 9/15$374
This United Airlines deal was found by Cheapflights users on 9/15. 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 9/304:57 pmPWM - ONT
1 stop8h 33mUnited Airlines
Sat 10/46:51 pmONT - PWM
2 stops11h 20mUnited Airlines
Deal found 9/15$418
This Delta deal was found by Cheapflights users on 9/17. 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 10/241:46 pmPWM - ONT
2 stops11h 36mDelta
Tue 10/2811:36 amONT - PWM
1 stop7h 43mDelta
Deal found 9/17$423
This JetBlue deal was found by Cheapflights users on 9/16. 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.
Fri 9/262:17 pmPWM - ONT
1 stop10h 12mJetBlue
Tue 9/3010:56 pmONT - PWM
1 stop11h 26mJetBlue
Deal found 9/16$424
This Delta deal was found by Cheapflights users on 9/17. 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 10/241:46 pmPWM - ONT
2 stops11h 36mDelta
Mon 10/2710:00 pmONT - PWM
2 stops11h 00mDelta
Deal found 9/17$428
This United Airlines deal was found by Cheapflights users on 9/16. 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 11/173:20 pmPWM - ONT
1 stop8h 24mUnited Airlines
Wed 11/195:05 amONT - PWM
1 stop7h 43mUnited Airlines
Deal found 9/16$445

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 September 17, 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

Wed 1/14

5:30 am-11:38 am

1 stop9h 08m

Ontario

Thu 1/22

10:30 pm-11:00 am

2 stops9h 30m

$302

PortlandOntario

PWM - ONT

PWMONT

Portland

Tue 1/13

5:30 am-11:38 am

1 stop9h 08m

Ontario

Tue 1/20

10:30 pm-1:51 pm

2 stops12h 21m

$302

PortlandOntario

PWM - ONT

PWMONT

Portland

Tue 1/13

5:30 am-11:38 am

1 stop9h 08m

Ontario

Thu 1/22

10:30 pm-11:00 am

2 stops9h 30m

$302

PortlandOntario

PWM - ONT

PWMONT

Portland

Sat 11/1

1:27 pm-7:19 pm

1 stop8h 52m

Ontario

Mon 11/3

10:00 pm-1:06 pm

2 stops12h 06m

$302

PortlandOntario

PWM - ONT

PWMONT

Portland

Wed 1/14

5:30 am-11:38 am

1 stop9h 08m

Ontario

Tue 1/20

10:30 pm-11:00 am

2 stops9h 30m

$302

PortlandOntario

PWM - ONT

PWMONT

Portland

Tue 1/13

5:30 am-11:38 am

1 stop9h 08m

Ontario

Wed 1/21

10:30 pm-11:00 am

2 stops9h 30m

$312

PortlandOntario

PWM - ONT

PWMONT

Portland

Wed 11/12

1:25 pm-7:37 pm

1 stop9h 12m

Ontario

Sat 11/15

11:45 am-10:19 pm

1 stop7h 34m

$328

PortlandOntario

PWM - ONT

PWMONT

Portland

Sun 1/18

5:30 am-11:38 am

1 stop9h 08m

$149

PortlandOntario

PWM - ONT

PWMONT

Portland

Fri 10/31

4:54 pm-10:31 pm

1 stop8h 37m

$169

PortlandOntario

PWM - ONT

PWMONT

Portland

Wed 1/7

4:10 pm-10:26 pm

1 stop9h 16m

$176

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/16

Showing 1-10 of 15 results
1
2

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 $327). 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 September 17, 2025.
Read reviews from past customers who have flown Delta and American Airlines 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.
Delta
8.0
Very good
7,961 reviews

Overall

8.0

Boarding

8.2

Crew

8.5

Comfort

7.9

Food

7.3

Entertainment

7.9

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
7,961 reviews
Delta
8.0
Very good
7,961 reviews

Overall

8.0

Boarding

8.2

Crew

8.5

Comfort

7.9

Food

7.3

Entertainment

7.9

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
American Airlines
7.2
Good
10,000 reviews
Delta
8.0
Very good
7,961 reviews

Overall

8.0

Boarding

8.2

Crew

8.5

Comfort

7.9

Food

7.3

Entertainment

7.9

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 Portland 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 Portland, Maine to Ontario?

    Airlines like Delta fly from Portland, Maine to Ontario in about 9h 08m. The time it takes to get you to your destination can typically vary by up to . There are 2590 mi between Portland, Maine and Ontario.

  • 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. An alternate airline flying to your destination would be Delta. Users have found that American Airlines is 51% cheaper than the other options available to this destination.

  • 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 $327). 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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Alternative routes for Portland to Ontario

See prices for flight routes from nearby airports that may be better suited for you.
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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 September 17, 2025.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$279Average$592FlexibilityNo cancel feeOn-time71%
DeltaCheapest$302Average$442FlexibilityNo cancel feeOn-timeN/A

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