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Ontario

$135+ 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 6/4. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — ONT
Mar 23 — Mar 301
Mon 3/23
Mon 3/30
1 adult, Economy
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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 February 21, 2026.

This JetBlue deal was found by Cheapflights users on 2/18. 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.
Tue 5/262:18 pm
PWM
-
ONT
1 stop10h 51m
JetBlue
Fri 5/2911:25 pm
ONT
-
PWM
1 stop10h 58m
JetBlue
Deal found 2/18$303
This United Airlines deal was found by Cheapflights users on 2/20. 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 3/174:23 pm
PWM
-
ONT
1 stop8h 55m
United Airlines
Tue 3/2411:59 pm
ONT
-
PWM
2 stops10h 58m
United Airlines
Deal found 2/20$348
This Delta deal was found by Cheapflights users on 2/20. 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.
Tue 3/1711:45 am
PWM
-
ONT
2 stops12h 15m
Delta
Tue 3/2410:25 pm
ONT
-
PWM
2 stops9h 39m
Delta
Deal found 2/20$353
This United Airlines deal was found by Cheapflights users on 2/20. 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 5/63:23 pm
PWM
-
ONT
1 stop8h 13m
United Airlines
Sun 5/105:00 am
ONT
-
PWM
1 stop7h 41m
United Airlines
Deal found 2/20$354
This Delta deal was found by Cheapflights users on 2/19. 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 8/201:35 pm
PWM
-
ONT
1 stop11h 21m
Delta
Sun 8/2310:59 pm
ONT
-
PWM
1 stop10h 23m
Delta
Deal found 2/19$389
This American Airlines deal was found by Cheapflights users on 2/18. 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.
Fri 5/111:56 am
PWM
-
ONT
2 stops13h 40m
American Airlines
Tue 5/54:52 pm
ONT
-
PWM
2 stops14h 15m
American Airlines
Deal found 2/18$392
This Delta deal was found by Cheapflights users on 2/20. 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 5/66:30 am
PWM
-
ONT
2 stops15h 03m
Delta
Sun 5/105:50 pm
ONT
-
PWM
2 stops15h 07m
Delta
Deal found 2/20$393
This Southwest deal was found by Cheapflights users on 2/20. 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.
Tue 3/174:30 pm
PWM
-
ONT
1 stop8h 10m
Southwest
Tue 3/249:55 pm
ONT
-
PWM
1 stop11h 00m
Southwest
Deal found 2/20$398
This United Airlines deal was found by Cheapflights users on 2/19. 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 6/36:00 am
PWM
-
ONT
2 stops14h 28m
United Airlines
Fri 6/56:30 pm
ONT
-
PWM
2 stops12h 37m
United Airlines
Deal found 2/19$399
This Southwest deal was found by Cheapflights users on 2/19. 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.
Wed 5/61:00 pm
PWM
-
ONT
2 stops9h 35m
Southwest
Sun 5/1011:55 pm
ONT
-
PWM
2 stops11h 15m
Southwest
Deal found 2/19$403

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 February 21, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$303
(JetBlue)

One-way from

$135
(Priceline)

Popular in

April

Cheapest in

January

Average price

$359
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. 4% potential increase in price ($16 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($6 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in February 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 February 21, 2026.
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 5/6

4:45 pm-10:30 pm

1 stop8h 45m

Ontario

Sun 5/10

5:00 am-3:41 pm

1 stop7h 41m

$354

PortlandOntario

PWM - ONT

PWMONT

Portland

Fri 5/1

4:45 pm-10:30 pm

1 stop8h 45m

Ontario

Tue 5/5

5:00 am-3:41 pm

1 stop7h 41m

$354

PortlandOntario

PWM - ONT

PWMONT

Portland

Wed 6/3

4:51 pm-10:46 pm

1 stop8h 55m

Ontario

Fri 6/5

6:30 pm-10:07 am

2 stops12h 37m

$394

PortlandOntario

PWM - ONT

PWMONT

Portland

Wed 5/6

1:00 pm-7:35 pm

2 stops9h 35m

Ontario

Sun 5/10

11:55 pm-2:10 pm

2 stops11h 15m

$403

PortlandOntario

PWM - ONT

PWMONT

Portland

Sun 5/3

5:30 am-3:10 pm

1 stop12h 40m

Ontario

Fri 5/8

8:10 am-11:25 pm

2 stops12h 15m

$410

PortlandOntario

PWM - ONT

PWMONT

Portland

Tue 5/5

4:45 pm-10:30 pm

1 stop8h 45m

Ontario

Sat 5/9

5:00 am-3:41 pm

1 stop7h 41m

$419

PortlandOntario

PWM - ONT

PWMONT

Portland

Wed 5/6

6:00 am-5:52 pm

2 stops14h 52m

Ontario

Sat 5/9

5:00 am-3:41 pm

1 stop7h 41m

$448

PortlandOntario

PWM - ONT

PWMONT

Portland

Tue 5/19

4:45 pm-10:30 pm

1 stop8h 45m

Ontario

Wed 5/27

6:30 pm-9:11 am

2 stops11h 41m

$459

PortlandOntario

PWM - ONT

PWMONT

Portland

Tue 4/28

4:23 pm-10:26 pm

1 stop9h 03m

$210

PortlandOntario

PWM - ONT

PWMONT

Portland

Wed 5/6

4:45 pm-10:30 pm

1 stop8h 45m

$210

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/17

Showing 1-10 of 16 results
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 February.
ProviderPrice AccuracyTrust Score*
FlightHubPrice Accuracy3 starsTrust Score*3 stars
ExpediaPrice Accuracy1 starTrust 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.

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 $115). Flying from Portland, Maine to Ontario in April is currently the most expensive (average of $179). 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 February 21, 2026.
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
7.9
Good
8,228 reviews

Crew

8.5

Overall

7.9

Food

7.2

Boarding

8.1

Entertainment

7.8

Comfort

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
7.9
Good
8,228 reviews
Delta
7.9
Good
8,228 reviews

Crew

8.5

Overall

7.9

Food

7.2

Boarding

8.1

Entertainment

7.8

Comfort

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
11,334 reviews
Delta
7.9
Good
8,228 reviews

Crew

8.5

Overall

7.9

Food

7.2

Boarding

8.1

Entertainment

7.8

Comfort

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 United Airlines fly from Portland, Maine to Ontario in about 8h 45m. 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?

    Delta, at $259, was found to be the cheapest airline from Portland, Maine to Ontario. An alternate airline flying to your destination would be American Airlines.

  • 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 American Airlines ($118), United Airlines ($118), and Delta ($148).

  • 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 $115). Flying from Portland, Maine to Ontario in April is currently the most expensive (average of $179). 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

Browse thousands of different options on Cheapflights for your next trip

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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 February 21, 2026.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$259Average$363FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$279Average$414FlexibilityNo cancel feeOn-time71%

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