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

Delta, at $297, was found to be the cheapest airline from Portland, Maine to Ontario.Alternate airlines to your destination round-trip include American Airlines and JetBlue. Users have found that Delta is 47% 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 Delta ($149), Frontier ($150), and JetBlue ($156).

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 $459. You can even find prices in January for less than $459, 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 23%.

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.

$149+ Flights from Portland, ME to Ontario

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1. Tell us where you want to go

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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	$297 (Delta)
One-way from	$149 (Delta)
Popular in	December
Cheapest in	September
Average price	$402

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. 16% potential increase in price ($107 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 6% potential price decrease ($35 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in April 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 April 15, 2025.

Sat 5/105:30 amPWM - ONT

1 stop8h 38mDelta

Tue 5/2012:18 pmONT - PWM

1 stop8h 41mDelta

Deal found 4/14

$297

Sat 5/102:02 pmPWM - ONT

1 stop10h 03mAmerican Airlines

Tue 5/207:25 pmONT - PWM

2 stops13h 23mAmerican Airlines

Deal found 4/14

$306

Wed 6/182:20 pmPWM - ONT

1 stop11h 10mJetBlue

Tue 6/2411:45 pmONT - PWM

1 stop10h 38mJetBlue

Deal found 4/14

$349

Wed 5/212:20 pmPWM - ONT

2 stops10h 55mSouthwest

Mon 5/267:20 pmONT - PWM

2 stops13h 10mSouthwest

Deal found 4/14

$416

Wed 4/306:15 amPWM - ONT

2 stops12h 02mUnited Airlines

Tue 5/66:00 amONT - PWM

2 stops14h 27mUnited Airlines

Deal found 4/13

$432

Fri 5/302:05 pmPWM - ONT

2 stops12h 52mAlaska Airlines

Fri 6/64:45 pmONT - PWM

2 stops14h 56mAlaska Airlines

Deal found 4/15

$887

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 April 15, 2025.

Sat 5/105:30 amPWM - ONT

1 stop8h 38mDelta

Tue 5/2012:18 pmONT - PWM

1 stop8h 41mDelta

Deal found 4/14

$297

Sat 5/102:02 pmPWM - ONT

1 stop10h 03mAmerican Airlines

Tue 5/207:25 pmONT - PWM

2 stops13h 23mAmerican Airlines

Deal found 4/14

$306

Wed 6/182:20 pmPWM - ONT

1 stop11h 10mJetBlue

Tue 6/2411:45 pmONT - PWM

1 stop10h 38mJetBlue

Deal found 4/14

$349

Wed 5/212:20 pmPWM - ONT

2 stops10h 55mSouthwest

Mon 5/267:20 pmONT - PWM

2 stops13h 10mSouthwest

Deal found 4/14

$416

Wed 4/306:15 amPWM - ONT

2 stops12h 02mUnited Airlines

Tue 5/66:00 amONT - PWM

2 stops14h 27mUnited Airlines

Deal found 4/13

$432

Fri 5/302:05 pmPWM - ONT

2 stops12h 52mAlaska Airlines

Fri 6/64:45 pmONT - PWM

2 stops14h 56mAlaska Airlines

Deal found 4/15

$887

Last-minute flights from Portland to Ontario
Discover last-minute flight deals from Portland to Ontario. Data last updated April 15, 2025 and is based on user searches.

Thu 4/246:15 amPWM - ONT

2 stops14h 36mUnited Airlines

Tue 5/66:00 amONT - PWM

2 stops14h 27mUnited Airlines

Deal found 4/13

$487

Wed 4/306:15 amPWM - ONT

2 stops12h 02mUnited Airlines

Tue 5/66:00 amONT - PWM

2 stops14h 27mUnited Airlines

Deal found 4/13

$432

Sat 5/105:30 amPWM - ONT

1 stop8h 38mDelta

Tue 5/2012:18 pmONT - PWM

1 stop8h 41mDelta

Deal found 4/14

$297

Sat 5/102:02 pmPWM - ONT

1 stop10h 03mAmerican Airlines

Tue 5/207:25 pmONT - PWM

2 stops13h 23mAmerican Airlines

Deal found 4/14

$306

Wed 5/212:20 pmPWM - ONT

2 stops10h 55mSouthwest

Mon 5/267:20 pmONT - PWM

2 stops13h 10mSouthwest

Deal found 4/14

$416

Fri 5/303:35 pmPWM - ONT

1 stop8h 36mJetBlue

Fri 6/610:40 pmONT - PWM

1 stop11h 40mJetBlue

Deal found 4/14

$407

Fri 5/302:05 pmPWM - ONT

2 stops12h 52mAlaska Airlines

Fri 6/64:45 pmONT - PWM

2 stops14h 56mAlaska Airlines

Deal found 4/15

$887

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 April 15, 2025.

Tue 5/205:30 amPWM - ONT

1 stop8h 38mDelta

Deal found 4/15

$149

Fri 5/169:30 pmPWM - ONT

2 stops29h 29mFrontier

Deal found 4/14

$150

Wed 5/213:35 pmPWM - ONT

1 stop8h 36mJetBlue

Deal found 4/14

$156

Sat 5/244:43 pmPWM - ONT

1 stop8h 43mUnited Airlines

Deal found 4/14

$169

Wed 5/282:05 pmPWM - ONT

2 stops12h 52mAlaska Airlines

Deal found 4/14

$174

Fri 4/1812:15 pmPWM - ONT

2 stops12h 55mAmerican Airlines

Deal found 4/13

$352

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

Sat 5/10

5:30 am-11:08 am

1 stop8h 38m

Ontario

Tue 5/20

12:18 pm-11:59 pm

1 stop8h 41m

$297

PortlandOntario

PWM - ONT

PWMONT

Portland

Sat 5/10

2:02 pm-9:05 pm

1 stop10h 03m

Ontario

Tue 5/20

7:25 pm-11:48 am

2 stops13h 23m

$306

PortlandOntario

PWM - ONT

PWMONT

Portland

Wed 6/18

2:20 pm-10:30 pm

1 stop11h 10m

Ontario

Tue 6/24

11:45 pm-1:23 pm

1 stop10h 38m

$349

PortlandOntario

PWM - ONT

PWMONT

Portland

Wed 5/21

2:20 pm-10:15 pm

2 stops10h 55m

Ontario

Mon 5/26

7:20 pm-11:30 am

2 stops13h 10m

$416

PortlandOntario

PWM - ONT

PWMONT

Portland

Wed 4/30

6:15 am-3:17 pm

2 stops12h 02m

Ontario

Tue 5/6

6:00 am-11:27 pm

2 stops14h 27m

$432

PortlandOntario

PWM - ONT

PWMONT

Portland

Fri 5/30

2:05 pm-11:57 pm

2 stops12h 52m

Ontario

Fri 6/6

4:45 pm-10:41 am

2 stops14h 56m

$887

PortlandOntario

PWM - ONT

PWMONT

Portland

Tue 5/20

5:30 am-11:08 am

1 stop8h 38m

$149

PortlandOntario

PWM - ONT

PWMONT

Portland

Fri 5/16

9:30 pm-11:59 pm

2 stops29h 29m

$150

PortlandOntario

PWM - ONT

PWMONT

Portland

Wed 5/21

3:35 pm-9:11 pm

1 stop8h 36m

$156

PortlandOntario

PWM - ONT

PWMONT

Portland

Sat 5/24

4:43 pm-10:26 pm

1 stop8h 43m

$169

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/15

Showing 1-10 of 12 results

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 April.

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

Alaska Airlines

8.0

Very good

9,871 reviews

Reviews

1 / 20

4.0

Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >

Alaska Airlines

8.0

Very good

9,871 reviews

Alaska Airlines

8.0

Very good

9,871 reviews

Reviews

1 / 20

4.0

Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >

Southwest

8.0

Very good

4,279 reviews

Alaska Airlines

8.0

Very good

9,871 reviews

Reviews

1 / 20

4.0

Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >

Delta

8.0

Very good

7,918 reviews

Alaska Airlines

8.0

Very good

9,871 reviews

Reviews

1 / 20

4.0

Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >

United Airlines

7.4

Good

8,658 reviews

Alaska Airlines

8.0

Very good

9,871 reviews

Reviews

1 / 20

4.0

Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >

JetBlue

7.3

Good

2,927 reviews

Alaska Airlines

8.0

Very good

9,871 reviews

Reviews

1 / 20

4.0

Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >

Related info for your journey

What are the cheapest airlines flying from Portland, Maine to Ontario round-trip?
Delta, at $297, was found to be the cheapest airline from Portland, Maine to Ontario.Alternate airlines to your destination round-trip include American Airlines and JetBlue. Users have found that Delta is 47% 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 Delta ($149), Frontier ($150), and JetBlue ($156).
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

Browse thousands of different options on Cheapflights for your next trip

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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$352	Average$562	FlexibilityNo cancel fee	On-time71%

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$149+ 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 5/20. 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 April 15, 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 April 15, 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 April.

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

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 April 15, 2025.