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Portland

$154+ Cheap flights from Ontario to Portland, ME (ONT - PWM)

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 1/23. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — PWM
Jan 10 — Jan 171
Sat 1/10
Sat 1/17
1 adult, Economy
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Cheap flight deals from Ontario to Portland

Cheapest flights from Ontario to Portland
Explore the most affordable flight options available from Ontario to Portland. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 11, 2025.

This Delta deal was found by Cheapflights users on 12/10. 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 12/2511:15 amONT - PWM
1 stop8h 28mDelta
Fri 12/265:45 amPWM - ONT
1 stop20h 38mDelta
Deal found 12/10$742
This United Airlines deal was found by Cheapflights users on 12/10. 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 12/2411:59 pmONT - PWM
2 stops10h 40mUnited Airlines
Tue 12/3010:19 amPWM - ONT
2 stops29h 19mUnited Airlines
Deal found 12/10$762
This Delta deal was found by Cheapflights users on 12/10. 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 12/2511:15 amONT - PWM
1 stop8h 28mDelta
Tue 12/305:45 amPWM - ONT
1 stop17h 05mDelta
Deal found 12/10$772
This Delta deal was found by Cheapflights users on 12/10. 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 12/2511:15 amONT - PWM
1 stop8h 28mDelta
Sat 12/275:45 amPWM - ONT
1 stop31h 15mDelta
Deal found 12/10$802
This Southwest deal was found by Cheapflights users on 12/10. 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.
Sun 12/289:30 amONT - PWM
1 stop11h 35mSouthwest
Tue 12/305:30 amPWM - ONT
2 stops11h 05mSouthwest
Deal found 12/10$830
This Delta deal was found by Cheapflights users on 12/10. 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 12/2411:15 amONT - PWM
1 stop8h 28mDelta
Fri 12/265:45 amPWM - ONT
1 stop20h 38mDelta
Deal found 12/10$863
This Delta deal was found by Cheapflights users on 12/10. 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 12/2411:15 amONT - PWM
1 stop8h 28mDelta
Mon 12/295:45 amPWM - ONT
1 stop20h 38mDelta
Deal found 12/10$893
This American Airlines deal was found by Cheapflights users on 12/10. 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 12/2411:59 pmONT - PWM
1 stop8h 21mAmerican Airlines
Tue 12/306:41 pmPWM - ONT
2 stops20h 12mAmerican Airlines
Deal found 12/10$913
This United Airlines deal was found by Cheapflights users on 12/10. 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.
Thu 12/116:00 amONT - PWM
2 stops14h 09mUnited Airlines
Mon 12/224:10 pmPWM - ONT
1 stop9h 15mUnited Airlines
Deal found 12/10$917
This Delta deal was found by Cheapflights users on 12/10. 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 12/2411:15 amONT - PWM
1 stop8h 28mDelta
Sun 12/285:45 amPWM - ONT
1 stop20h 38mDelta
Deal found 12/10$923

Find flight deals from Ontario to Portland

Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) to Portland (PWM). 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 December 11, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$407
(United Airlines)

One-way from

$154
(Delta)

Popular in

July

Cheapest in

April

Average price

$539
Provider with most accurate pricing for Ontario-Portland flight deals.
Search Deals
Provider most trusted by Cheapflights users for Ontario-Portland flights.
Search Deals
From Ontario to Portland
Search Deals
One-way flight from Ontario to Portland
Search Deals
Highest demand for flights based on searches. 7% potential increase in price ($36 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease ($18 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 2025
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Ontario to Portland 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 December 11, 2025.
Use the filters below to find and compare flights from Ontario to Portland that are best for you.

Fly from

Ontario

Fly to

Portland

Route

Depart

Return

Price

OntarioPortland

ONT - PWM

ONTPWM

Ontario

Sat 4/18

12:00 pm-11:59 pm

2 stops32h 59m

Portland

Wed 4/22

6:30 am-6:15 pm

2 stops14h 45m

$412

OntarioPortland

ONT - PWM

ONTPWM

Ontario

Wed 4/15

12:00 pm-1:54 pm

2 stops22h 54m

Portland

Tue 4/21

6:00 am-11:20 am

1 stop8h 20m

$436

OntarioPortland

ONT - PWM

ONTPWM

Ontario

Sat 4/18

12:00 pm-11:59 pm

2 stops32h 59m

Portland

Tue 4/21

6:00 am-11:20 am

1 stop8h 20m

$438

OntarioPortland

ONT - PWM

ONTPWM

Ontario

Wed 4/15

7:00 am-10:58 pm

2 stops12h 58m

Portland

Wed 4/22

4:23 pm-10:26 pm

1 stop9h 03m

$463

OntarioPortland

ONT - PWM

ONTPWM

Ontario

Wed 4/15

12:00 pm-1:54 pm

2 stops22h 54m

Portland

Thu 4/23

6:30 am-6:15 pm

2 stops14h 45m

$471

OntarioPortland

ONT - PWM

ONTPWM

Ontario

Sat 4/18

12:00 pm-11:59 pm

2 stops32h 59m

Portland

Thu 4/23

6:30 am-6:15 pm

2 stops14h 45m

$473

OntarioPortland

ONT - PWM

ONTPWM

Ontario

Wed 1/14

1:24 pm-9:01 am

2 stops16h 37m

Portland

Sun 1/18

6:00 am-5:43 pm

2 stops14h 43m

$491

OntarioPortland

ONT - PWM

ONTPWM

Ontario

Thu 4/16

12:00 pm-11:59 pm

2 stops32h 59m

Portland

Tue 4/21

6:00 am-11:20 am

1 stop8h 20m

$508

OntarioPortland

ONT - PWM

ONTPWM

Ontario

Sun 4/19

10:59 pm-11:59 pm

2 stops22h 00m

Portland

Tue 4/21

6:00 am-6:15 pm

2 stops15h 15m

$522

OntarioPortland

ONT - PWM

ONTPWM

Ontario

Tue 1/6

6:32 pm-9:01 am

2 stops11h 29m

$181

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/11

Showing 1-10 of 19 results
1
2

Compare providers for flights from Ontario to Portland

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 Ontario to Portland in December.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
eDreamsPrice 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 Ontario-Portland, Maine flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Ontario-Portland, Maine flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Ontario-Portland, Maine flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Ontario-Portland, Maine flights, Cheapflights users trust eDreams the most. eDreams 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 Ontario-Portland, Maine 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 Ontario to Portland

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

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

Currently, April is the cheapest month in which you can book a flight from Ontario to Portland, Maine (average of $85). Flying from Ontario to Portland, Maine in May is currently the most expensive (average of $188). 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.

What is the cheapest time of day to fly from ONT to PWM?

Find hourly flight availability from Ontario to Portland. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated December 11, 2025.

A simple way to save on the total cost of your ticket is to fly from Ontario to Portland, Maine in the evening. If you’re flexible enough to do this you can expect to save up to 35% on your trip compared to booking a flight in the morning.

Reviews of airlines servicing Portland

Get insights into the airlines that provide service to Portland. 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 Portland. Reviews last updated December 11, 2025.
Peruse reviews from past customers who have flown with Southwest, Delta, and United Airlines from Ontario to Portland to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
7.9
Good
4,253 reviews

Crew

8.6

Food

7.0

Entertainment

7.5

Boarding

8.1

Comfort

8.0

Overall

7.9

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.
Southwest
7.9
Good
4,253 reviews
Southwest
7.9
Good
4,253 reviews

Crew

8.6

Food

7.0

Entertainment

7.5

Boarding

8.1

Comfort

8.0

Overall

7.9

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.
Delta
7.9
Good
8,008 reviews
Southwest
7.9
Good
4,253 reviews

Crew

8.6

Food

7.0

Entertainment

7.5

Boarding

8.1

Comfort

8.0

Overall

7.9

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.
United Airlines
7.4
Good
9,095 reviews
Southwest
7.9
Good
4,253 reviews

Crew

8.6

Food

7.0

Entertainment

7.5

Boarding

8.1

Comfort

8.0

Overall

7.9

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.
American Airlines
7.2
Good
11,050 reviews
Southwest
7.9
Good
4,253 reviews

Crew

8.6

Food

7.0

Entertainment

7.5

Boarding

8.1

Comfort

8.0

Overall

7.9

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.

Related info for your journey

Find useful and relevant information for your journey from Ontario to Portland. 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 Ontario to Portland, Maine?

    There are many flights that can get you from Ontario to Portland, Maine in 14h 48m. Fly via United Airlines or Delta to get the fastest option. There are 2590 mi between Ontario and Portland, Maine. Both multi-stop and nonstop flights can be found to your destination and back.

  • What are the cheapest airlines flying from Ontario to Portland, Maine round-trip?

    Currently priced at $148, Delta will fly you from Ontario to Portland, Maine and back. In addition to Delta, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from American Airlines and United Airlines - these airlines can fly you to your destination from $266 and $380, respectively. Delta is 67% cheaper than the average price of flights available within the next 90 days to this destination.

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

    $125 is the cheapest one-way deal found within the past few days, from American Airlines. You may also be able to find cheap deals on Southwest and Delta, with prices starting from $148 and $148, respectively.

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

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

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

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

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

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

    Currently, April is the cheapest month in which you can book a flight from Ontario to Portland, Maine (average of $85). Flying from Ontario to Portland, Maine in May is currently the most expensive (average of $188). 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

Traveling to a place near Portland?

Book flights to Portland if you plan to visit one of these locations
North Conway
Brunswick
Auburn
Conway

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Top 4 airlines flying from Ontario to Portland

Discover the top 4 airlines that operate flights from Ontario to Portland. 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 December 11, 2025.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$148Average$338FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$266Average$407FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$380Average$457FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$383Average$618FlexibilityNo cancel feeOn-time63%

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