HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
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 6/5. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — ONT
3月 30 — 4月 61
週一 3/30
週一 4/6
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Portland to Ontario with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

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 2月 28, 2026.

This KAYAK deal was found by Cheapflights users on 2/24. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
週三 6/102:25 pm
PWM
-
ONT
1 stop9h 20m
JetBlue
週一 6/2211:59 pm
ONT
-
PWM
1 stop10h 30m
JetBlue
Deal found 2/24$342
This Delta deal was found by Cheapflights users on 2/24. 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.
週二 3/315:23 am
PWM
-
ONT
1 stop9h 24m
Delta
週二 4/710:25 pm
ONT
-
PWM
2 stops9h 39m
Delta
Deal found 2/24$366
This Southwest deal was found by Cheapflights users on 2/24. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
週一 3/302:50 pm
PWM
-
ONT
2 stops10h 35m
Southwest
週三 4/811:55 pm
ONT
-
PWM
2 stops11h 15m
Southwest
Deal found 2/24$374
This Southwest deal was found by Cheapflights users on 2/24. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
週二 3/315:30 am
PWM
-
ONT
2 stops11h 30m
Southwest
週四 4/911:55 pm
ONT
-
PWM
2 stops11h 15m
Southwest
Deal found 2/24$380
This KAYAK deal was found by Cheapflights users on 2/24. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
週三 6/102:25 pm
PWM
-
ONT
1 stop9h 20m
JetBlue
週六 6/2011:59 pm
ONT
-
PWM
1 stop10h 30m
JetBlue
Deal found 2/24$385
This Delta deal was found by Cheapflights users on 2/24. 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.
週二 8/181:35 pm
PWM
-
ONT
1 stop11h 21m
Delta
週日 8/2310:59 pm
ONT
-
PWM
1 stop10h 23m
Delta
Deal found 2/24$389
This Delta deal was found by Cheapflights users on 2/24. 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.
週四 8/206:30 am
PWM
-
ONT
2 stops14h 31m
Delta
週日 8/2310:59 pm
ONT
-
PWM
1 stop10h 23m
Delta
Deal found 2/24$394
This Delta deal was found by Cheapflights users on 2/24. 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.
週三 4/15:23 am
PWM
-
ONT
1 stop9h 24m
Delta
週二 4/710:25 pm
ONT
-
PWM
2 stops9h 39m
Delta
Deal found 2/24$402
This United Airlines deal was found by Cheapflights users on 2/24. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
週二 5/53:23 pm
PWM
-
ONT
1 stop8h 13m
United Airlines
週六 5/95:00 am
ONT
-
PWM
1 stop7h 41m
United Airlines
Deal found 2/24$408

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 2月 28, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$342
(KAYAK)

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 2月 28, 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

PortlandOntario

PWM - ONT

PWMONT

Portland

週二 5/5

4:45 pm-10:30 pm

1 stop8h 45m

Ontario

週六 5/9

5:00 am-3:41 pm

1 stop7h 41m

$408

PortlandOntario

PWM - ONT

PWMONT

Portland

週三 5/20

4:45 pm-10:30 pm

1 stop8h 45m

Ontario

週日 5/24

6:30 am-5:44 pm

1 stop8h 14m

$443

PortlandOntario

PWM - ONT

PWMONT

Portland

週二 3/17

5:23 am-11:47 am

1 stop9h 24m

Ontario

週三 4/1

12:57 pm-11:22 pm

1 stop7h 25m

$523

PortlandOntario

PWM - ONT

PWMONT

Portland

週日 3/29

5:30 am-5:50 pm

1 stop15h 20m

Ontario

週四 4/2

9:55 pm-11:55 am

1 stop11h 00m

$560

PortlandOntario

PWM - ONT

PWMONT

Portland

週二 3/31

7:33 pm-10:45 pm

2 stops30h 12m

Ontario

週四 4/9

1:34 pm-10:22 am

2 stops17h 48m

$574

PortlandOntario

PWM - ONT

PWMONT

Portland

週二 6/9

4:51 pm-10:46 pm

1 stop8h 55m

Ontario

週日 6/21

5:00 am-3:49 pm

1 stop7h 49m

$622

PortlandOntario

PWM - ONT

PWMONT

Portland

週二 7/7

2:25 pm-10:40 pm

1 stop11h 15m

Ontario

週二 7/14

11:59 pm-1:29 pm

1 stop10h 30m

$623

PortlandOntario

PWM - ONT

PWMONT

Portland

週四 3/19

5:23 am-11:47 am

1 stop9h 24m

Ontario

週六 3/28

12:57 pm-11:22 pm

1 stop7h 25m

$649

PortlandOntario

PWM - ONT

PWMONT

Portland

週三 6/10

4:51 pm-10:46 pm

1 stop8h 55m

Ontario

週日 6/21

5:00 am-3:49 pm

1 stop7h 49m

$662

PortlandOntario

PWM - ONT

PWMONT

Portland

週二 3/17

5:23 am-11:47 am

1 stop9h 24m

Ontario

週日 3/29

10:25 pm-11:04 am

2 stops9h 39m

$728

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/26

Showing 1-10 of 23 resultsSorted by cheapest first
1
2
3

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 2月 28, 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
8,245 reviews

Boarding

8.1

Entertainment

7.8

Crew

8.5

Comfort

7.9

Food

7.2

Overall

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
8,245 reviews
Delta
7.9
Good
8,245 reviews

Boarding

8.1

Entertainment

7.8

Crew

8.5

Comfort

7.9

Food

7.2

Overall

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
11,367 reviews
Delta
7.9
Good
8,245 reviews

Boarding

8.1

Entertainment

7.8

Crew

8.5

Comfort

7.9

Food

7.2

Overall

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, Delta, and Southwest 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 6h 35m. There are 2590 mi between Portland, Maine and Ontario. Both multi-stop and nonstop flights can be found to your destination and back.

  • 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

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

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 2月 28, 2026.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$259Average$363FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$279Average$456FlexibilityNo cancel feeOn-time71%

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.