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

American Airlines, at $277, was found to be the cheapest airline from Portland, Maine to Ontario.Alternate airlines to your destination round-trip include JetBlue and Delta. Users have found that American Airlines is 51% cheaper than the other options available to this destination.

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 JetBlue ($146), United Airlines ($169), and Alaska Airlines ($299).

What is the cheapest day to fly from Portland, Maine to Ontario?

Travelers seeking maximum savings on their Portland, Maine to Ontario flight should consider departing on Tuesday afternoons when fares are most often at their lowest. Thursday mornings flights should be avoided if possible as fares are typically the most expensive at this time.

What is the cheapest day to fly round-trip from Portland, Maine to Ontario?

It’s generally more expensive to depart on a Friday, if you have to leave on this day you can still search on Cheapflights to find great options that meet your needs.

How far in advance should I book a flight from Portland, Maine to Ontario?

Travelers have found it’s best to book a flight 58 days in advance to save up to 129% compared to booking the same week of travel. As your travel date approaches, the cost of this flight route may potentially increase. While opting to book 58 days out may not be an option for all, there are still additional ways to secure a deal in the near future. You might find a flight from Portland, Maine to Ontario 1-2 weeks in advance for as low as $432, or $611 for flights within the next 24 hours.

What is the cheapest month to fly from Portland, Maine to Ontario?

The best pricing can be found in the month of January. Prices to Ontario from Portland, Maine average $458. You can even find prices in January for less than $458, as users have found deals to Ontario from as low as $236. The month of May appears to be one of the more expensive times to travel to Ontario from Portland, Maine. Flying in the targeted month can save you up to 22%.

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

One of the essential ways to save on airfare from Portland, Maine to Ontario is to remain as flexible as possible. Flights that are in the morning tend to be the most expensive. A flight in the afternoon could potentially save you up to 34% on airfare.

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 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 Portland, Maine-Ontario flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

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.

$146+ Flights from Portland, ME to Ontario - Compare & Save Big

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Cheap flight deals from Portland to Ontario

Most accurate provider	FlightHub 3 stars
Most trusted provider	eDreams 3 stars
Round-trip from	$277 (American Airlines)
One-way from	$146 (JetBlue)
Popular in	December
Cheapest in	September
Average price	$384

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. 14% potential increase in price ($96 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 6% potential price decrease ($34 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in May 2025

Search Deals

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 May 1, 2025.

Fri 5/301:12 pmPWM - ONT

1 stop10h 53mAmerican Airlines

Fri 6/67:02 pmONT - PWM

2 stops12h 39mAmerican Airlines

Deal found 4/29

$272

Thu 6/54:43 pmPWM - ONT

1 stop8h 43mUnited Airlines

Tue 6/106:32 pmONT - PWM

2 stops13h 01mUnited Airlines

Deal found 4/29

$279

Fri 7/42:19 pmPWM - ONT

1 stop10h 40mJetBlue

Tue 7/811:45 pmONT - PWM

1 stop10h 38mJetBlue

Deal found 4/30

$291

Fri 5/305:30 amPWM - ONT

1 stop8h 38mDelta

Fri 6/612:18 pmONT - PWM

1 stop8h 41mDelta

Deal found 4/30

$297

Tue 7/2912:26 pmPWM - ONT

2 stops14h 33mAlaska Airlines

Sun 8/36:00 amONT - PWM

2 stops11h 30mAlaska Airlines

Deal found 4/28

$994

Best flights from Portland to Ontario
Discover carefully curated flight deals from Portland to Ontario that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated May 1, 2025.

Fri 5/301:12 pmPWM - ONT

2 stops13h 31mAmerican Airlines

Fri 6/67:02 pmONT - PWM

2 stops12h 39mAmerican Airlines

Deal found 4/30

$277

Fri 7/42:19 pmPWM - ONT

1 stop10h 40mJetBlue

Tue 7/811:45 pmONT - PWM

1 stop10h 38mJetBlue

Deal found 4/30

$291

Fri 5/305:30 amPWM - ONT

1 stop8h 38mDelta

Fri 6/612:18 pmONT - PWM

1 stop8h 41mDelta

Deal found 4/30

$297

Wed 9/34:56 pmPWM - ONT

1 stop8h 34mUnited Airlines

Mon 9/86:38 pmONT - PWM

2 stops11h 46mUnited Airlines

Deal found 4/30

$379

Tue 5/132:05 pmPWM - ONT

2 stops12h 53mAlaska Airlines

Fri 5/166:00 amONT - PWM

2 stops13h 45mAlaska Airlines

Deal found 4/30

$1,035

Last-minute flights from Portland to Ontario
Discover last-minute flight deals from Portland to Ontario. Data last updated May 1, 2025 and is based on user searches.

Thu 5/14:40 pmPWM - ONT

2 stops9h 20mSouthwest

Mon 5/59:00 amONT - PWM

2 stops11h 20mSouthwest

Deal found 4/30

$752

Wed 5/76:00 amPWM - ONT

2 stops12h 09mUnited Airlines

Mon 5/265:10 amONT - PWM

1 stop7h 31mUnited Airlines

Deal found 4/30

$714

Sat 5/102:02 pmPWM - ONT

1 stop10h 03mAmerican Airlines

Tue 5/2010:40 pmONT - PWM

1 stop10h 59mAmerican Airlines

Deal found 4/30

$402

Sat 5/105:30 amPWM - ONT

1 stop8h 38mDelta

Tue 5/207:05 pmONT - PWM

2 stops13h 52mDelta

Deal found 4/30

$407

Tue 5/132:05 pmPWM - ONT

2 stops12h 53mAlaska Airlines

Fri 5/166:00 amONT - PWM

2 stops13h 45mAlaska Airlines

Deal found 4/30

$1,035

Thu 5/223:28 pmPWM - ONT

1 stop8h 36mUnited Airlines

Sun 5/257:00 amONT - PWM

2 stops13h 57mUnited Airlines

Deal found 4/30

$671

Fri 5/301:12 pmPWM - ONT

2 stops13h 31mAmerican Airlines

Fri 6/67:02 pmONT - PWM

2 stops12h 39mAmerican Airlines

Deal found 4/30

$277

Fri 5/305:30 amPWM - ONT

1 stop8h 38mDelta

Fri 6/612:18 pmONT - PWM

1 stop8h 41mDelta

Deal found 4/30

$297

One-way flights from Portland to Ontario
Search for one-way flight options from Portland to Ontario. Find affordable one-way fares based on user searches. Data last updated May 1, 2025.

Wed 8/202:20 pmPWM - ONT

1 stop11h 10mJetBlue

Deal found 4/30

$146

Sat 5/314:43 pmPWM - ONT

1 stop8h 43mUnited Airlines

Deal found 4/30

$169

Fri 8/152:07 pmPWM - ONT

2 stops13h 06mAlaska Airlines

Deal found 4/30

$299

Sun 7/206:35 pmPWM - ONT

1 stop8h 19mAmerican Airlines

Deal found 4/29

$437

Cheapflights Fare Finder

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

Fri 5/30

1:12 pm-9:05 pm

1 stop10h 53m

Ontario

Fri 6/6

7:02 pm-10:41 am

2 stops12h 39m

$272

PortlandOntario

PWM - ONT

PWMONT

Portland

Thu 6/5

4:43 pm-10:26 pm

1 stop8h 43m

Ontario

Tue 6/10

6:32 pm-10:33 am

2 stops13h 01m

$279

PortlandOntario

PWM - ONT

PWMONT

Portland

Fri 7/4

2:19 pm-9:59 pm

1 stop10h 40m

Ontario

Tue 7/8

11:45 pm-1:23 pm

1 stop10h 38m

$291

PortlandOntario

PWM - ONT

PWMONT

Portland

Fri 5/30

5:30 am-11:08 am

1 stop8h 38m

Ontario

Fri 6/6

12:18 pm-11:59 pm

1 stop8h 41m

$297

PortlandOntario

PWM - ONT

PWMONT

Portland

Tue 7/29

12:26 pm-11:59 pm

2 stops14h 33m

Ontario

Sun 8/3

6:00 am-8:30 pm

2 stops11h 30m

$994

PortlandOntario

PWM - ONT

PWMONT

Portland

Tue 6/3

3:06 pm-9:11 pm

1 stop9h 05m

$146

PortlandOntario

PWM - ONT

PWMONT

Portland

Sat 5/31

4:43 pm-10:26 pm

1 stop8h 43m

$169

PortlandOntario

PWM - ONT

PWMONT

Portland

Tue 6/3

2:05 pm-11:57 pm

2 stops12h 52m

$299

PortlandOntario

PWM - ONT

PWMONT

Portland

Sun 7/6

12:50 pm-8:50 pm

1 stop11h 00m

$417

PortlandOntario

PWM - ONT

PWMONT

Portland

Sun 7/20

6:35 pm-11:54 pm

1 stop8h 19m

$437

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/29

Compare providers for flights from Portland to Ontario

Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Portland to Ontario in May.

Provider	Price Accuracy	Trust Score*
Expedia	Price Accuracy1 star	Trust Score*3 stars
FlightHub	Price Accuracy3 stars	Trust Score*2 stars
eDreams	Price Accuracy3 stars	Trust 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 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 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 $246). Flying from Portland, Maine to Ontario in March is currently the most expensive (average of $328). 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.

Rainfall in Ontario by month

In terms of precipitation, rainfall in Ontario ranges from 0.1 - 3.4 inches per month. February is typically the wettest month, when rainfall can reach 3.4 in. June is typically the driest time to visit Ontario when rainfall is around 0.1 in.

Temperature in Ontario by month

If weather is an important factor for your trip to Ontario, use this chart to help with planning. For those seeking warmer temperatures, August is the ideal time of year to visit, when temperatures reach an average of 78.8 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 53.6 F).

Reviews of airlines servicing Ontario

To help decide which airline to fly from Portland to Ontario, see what other customers have to say about Alaska Airlines, Delta and United Airlines. 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.

Alaska Airlines

8.0

Very good

9,968 reviews

Reviews

1 / 20

10.0

Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Alaska Airlines

8.0

Very good

9,968 reviews

Alaska Airlines

8.0

Very good

9,968 reviews

Reviews

1 / 20

10.0

Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Delta

8.0

Very good

7,934 reviews

Alaska Airlines

8.0

Very good

9,968 reviews

Reviews

1 / 20

10.0

Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

United Airlines

7.4

Good

8,696 reviews

Alaska Airlines

8.0

Very good

9,968 reviews

Reviews

1 / 20

10.0

Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

JetBlue

7.3

Good

2,922 reviews

Alaska Airlines

8.0

Very good

9,968 reviews

Reviews

1 / 20

10.0

Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

American Airlines

7.2

Good

10,000 reviews

Alaska Airlines

8.0

Very good

9,968 reviews

Reviews

1 / 20

10.0

Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Related info for your journey

What are the cheapest airlines flying from Portland, Maine to Ontario round-trip?
American Airlines, at $277, was found to be the cheapest airline from Portland, Maine to Ontario.Alternate airlines to your destination round-trip include JetBlue and Delta. Users have found that American Airlines is 51% cheaper than the other options available to this destination.
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 JetBlue ($146), United Airlines ($169), and Alaska Airlines ($299).
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 $328). 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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Other flights to Ontario

Top 2 airlines flying from Portland to Ontario

Airline	Cheapest	Average	Flexibility	On-time
Delta	Cheapest$302	Average$442	FlexibilityNo cancel fee	On-timeN/A
American Airlines	Cheapest$332	Average$547	FlexibilityNo cancel fee	On-time71%

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$146+ 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 8/20. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Portland to Ontario with Cheapflights

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2. Select your favorite providers

3. Compare prices and book

Cheap flight deals from Portland to Ontario

Most accurate provider

Most trusted provider

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Find flight deals from Portland to Ontario

Cheapest flights from Portland to OntarioExplore 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 May 1, 2025.

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 May 1, 2025.

Cheapflights Fare Finder

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

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 May.

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.

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?

Rainfall in Ontario by month

Plan your trip to Ontario by taking into account the average rainfall totals by month.

Temperature in Ontario by month

Plan your trip to Ontario by taking into account the average temperature totals by month.

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 May 1, 2025.

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.

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

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

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

How can I find direct flights from Portland to Ontario?

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

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

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.

Alternative routes for Portland to Ontario

See prices for flight routes from nearby airports that may be better suited for you.

Top 2 airlines flying from Portland to Ontario

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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 May 1, 2025.