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Ontario

$181+ 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 9/11. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — ONT
Aug 28 — Sep 41
Fri 8/28
Fri 9/4
1 adult, Economy
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Find cheap flights from Portland to Ontario with Cheapflights

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Cheap 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 29, 2026.

This American Airlines deal was found by Cheapflights users on 7/24. 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 8/208:00 am
PWM
-
ONT
1 stop8h 31m
American Airlines
Tue 8/256:00 am
ONT
-
PWM
1 stop9h 52m
American Airlines
Deal found 7/24$361
This Southwest deal was found by Cheapflights users on 7/27. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/306:30 am
PWM
-
ONT
2 stops10h 55m
Southwest
Mon 11/211:25 am
ONT
-
PWM
2 stops9h 25m
Southwest
Deal found 7/27$371
This JetBlue deal was found by Cheapflights users on 7/25. 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 8/282:45 pm
PWM
-
ONT
1 stop10h 53m
JetBlue
Mon 8/3111:59 pm
ONT
-
PWM
1 stop9h 31m
JetBlue
Deal found 7/25$376
This Delta deal was found by Cheapflights users on 7/24. 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 12/1612:50 pm
PWM
-
ONT
2 stops13h 58m
Delta
Wed 1/67:00 am
ONT
-
PWM
2 stops13h 49m
Delta
Deal found 7/24$382
This American Airlines deal was found by Cheapflights users on 7/25. 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 12/165:46 am
PWM
-
ONT
2 stops11h 14m
American Airlines
Wed 1/66:27 am
ONT
-
PWM
2 stops13h 27m
American Airlines
Deal found 7/25$418
This Delta deal was found by Cheapflights users on 7/26. 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 11/254:40 pm
PWM
-
ONT
2 stops10h 18m
Delta
Wed 12/26:00 am
ONT
-
PWM
2 stops13h 23m
Delta
Deal found 7/26$430
This JetBlue deal was found by Cheapflights users on 7/28. 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.
Sat 8/222:40 pm
PWM
-
ONT
1 stop10h 19m
JetBlue
Fri 8/2811:59 pm
ONT
-
PWM
1 stop10h 46m
JetBlue
Deal found 7/28$446
This United Airlines deal was found by Cheapflights users on 7/27. 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 11/73:23 pm
PWM
-
ONT
1 stop8h 28m
United Airlines
Sat 11/145:00 am
ONT
-
PWM
1 stop8h 02m
United Airlines
Deal found 7/27$471
This United Airlines deal was found by Cheapflights users on 7/28. 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 10/275:30 am
PWM
-
ONT
2 stops13h 03m
United Airlines
Wed 10/285:00 am
ONT
-
PWM
1 stop8h 02m
United Airlines
Deal found 7/28$476

Find 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 29, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$361
(American Airlines)

One-way from

$181
(Delta)

Popular in

July

Cheapest in

September

Average price

$554
Provider with most accurate pricing for Portland-Ontario flight deals.
Search Deals
Provider most trusted by Cheapflights users for Portland-Ontario flights.
Search Deals
From Portland to Ontario
Search Deals
One-way flight from Portland to Ontario
Search Deals
Highest demand for flights based on searches. 15% potential increase in price ($79 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($12 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in July 2026
Search Deals

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 29, 2026.
Use the filters below to find and compare flights from Portland to Ontario that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

PortlandOntario

PWM - ONT

PWMONT

Portland

Thu 8/20

1:30 pm-10:59 pm

2 stops12h 29m

Ontario

Tue 8/25

6:00 am-6:52 pm

1 stop9h 52m

$366

PortlandOntario

PWM - ONT

PWMONT

Portland

Fri 10/30

6:30 am-2:25 pm

2 stops10h 55m

Ontario

Mon 11/2

11:25 am-11:50 pm

2 stops9h 25m

$371

PortlandOntario

PWM - ONT

PWMONT

Portland

Wed 1/13

11:25 am-10:14 pm

2 stops13h 49m

Ontario

Tue 1/19

7:00 am-11:06 pm

2 stops13h 06m

$372

PortlandOntario

PWM - ONT

PWMONT

Portland

Fri 1/15

5:59 pm-10:14 pm

2 stops31h 15m

Ontario

Tue 1/19

7:00 am-11:06 pm

2 stops13h 06m

$453
Quickest round-trip

PortlandOntario

PWM - ONT

PWMONT

Portland

Sat 11/7

3:23 pm-8:51 pm

1 stop8h 28m

Ontario

Sat 11/14

5:00 am-4:02 pm

1 stop8h 02m

$471

PortlandOntario

PWM - ONT

PWMONT

Portland

Sat 10/31

3:23 pm-8:51 pm

1 stop8h 28m

Ontario

Fri 11/6

5:00 am-4:02 pm

1 stop8h 02m

$471

PortlandOntario

PWM - ONT

PWMONT

Portland

Tue 10/27

5:50 am-6:47 pm

2 stops15h 57m

Ontario

Wed 10/28

5:00 am-4:02 pm

1 stop8h 02m

$476
Cheapest one-way

PortlandOntario

PWM - ONT

PWMONT

Portland

Fri 9/11

2:10 pm-8:05 pm

1 stop8h 55m

$181

PortlandOntario

PWM - ONT

PWMONT

Portland

Thu 8/20

2:14 pm-9:52 pm

1 stop10h 38m

$210

PortlandOntario

PWM - ONT

PWMONT

Portland

Thu 8/20

2:40 pm-10:38 pm

1 stop10h 58m

$229

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/26

Showing 1-10 of 15 resultsSorted by cheapest first
1
2

Compare providers for flights from Portland 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 Portland to Ontario in July.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Portland, Maine-Ontario flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Portland, Maine-Ontario flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Portland, Maine-Ontario flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Portland, Maine-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 Portland, Maine-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 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.

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 American Airlines, Southwest, and Delta fly from Portland, Maine to Ontario in about 10h 55m. The time it takes to get you to your destination can typically vary by up to 2h 54m. There are 2590 mi between Portland, Maine and Ontario. Both multi-stop and nonstop flights can be found to your destination and back.

  • 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.

See more FAQs

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