Frontier's UpFront Plus offers a guaranteed empty middle seat for extra comfort.
Frontier Airlines' Zone 1 boarding is available with carry-on purchase or special fare bundles.
$88+ Cheap flights from Portland to Ontario (PDX - 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 1/6. Fares are subject to change and may not be available on all flights or dates of travel.
PDX — ONT
Dec 6 — Dec 131
1 adult, Economy
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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.Cheapflights Tip: The best prices from Portland to Ontario are usually found in October or July, booked 47 days in advance, depart on a Friday or Saturday and return on a Friday
Cheap flight deals from Portland to Ontario
Discover tips and strategies to find the most affordable flight options for your journey from Portland (PDX) 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 November 6, 2025.
Most accurate provider | CheapOair 3 stars |
|---|---|
Most trusted provider | CheapOair 3 stars |
Round-trip from | $117 (Booking.com) |
One-way from | $88 (Alaska Airlines) |
Popular in | March |
Cheapest in | October |
Average price | $220 |
Good round-trip deal | $177 or less |
Good one-way deal | $117 or less |
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 November 6, 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 November 6, 2025.
This Booking.com deal was found by Cheapflights users on 11/5. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/1712:51 pmPDX - ONT
Nonstop2h 19mFrontier
Sun 11/2312:58 amONT - PDX
1 stop14h 18mFrontier
Deal found 11/5![Frontier logo]()
$117
This Frontier deal was found by Cheapflights users on 11/5. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/222:30 pmPDX - ONT
1 stop9h 27mFrontier
Sun 11/2312:29 pmONT - PDX
Nonstop2h 35mFrontier
Deal found 11/5![Frontier logo]()
$121
This CheapOair deal was found by Cheapflights users on 11/4. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/252:31 pmPDX - ONT
1 stop20h 57mFrontier
Thu 12/116:15 amONT - PDX
1 stop27h 19mFrontier
Deal found 11/4![Frontier logo]()
$127
This CheapOair deal was found by Cheapflights users on 11/5. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/412:51 pmPDX - ONT
1 stop25h 34mFrontier
Thu 12/116:15 amONT - PDX
1 stop27h 19mFrontier
Deal found 11/5![Frontier logo]()
$128
This Frontier deal was found by Cheapflights users on 11/4. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/1512:52 pmPDX - ONT
1 stop10h 58mFrontier
Mon 11/1712:05 pmONT - PDX
Nonstop2h 26mFrontier
Deal found 11/4![Frontier logo]()
$129
This Kiwi.com deal was found by Cheapflights users on 11/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/2510:06 amPDX - ONT
1 stop4h 20mFrontier
Sat 12/66:15 amONT - PDX
1 stop27h 19mFrontier
Deal found 11/4![Frontier logo]()
$132
This Booking.com deal was found by Cheapflights users on 11/5. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/285:28 pmPDX - ONT
1 stop16h 43mFrontier
Mon 12/112:29 pmONT - PDX
Nonstop2h 35mFrontier
Deal found 11/5![Frontier logo]()
$133
This CheapOair deal was found by Cheapflights users on 11/6. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/512:55 pmPDX - ONT
1 stop25h 30mFrontier
Sun 12/146:15 amONT - PDX
1 stop26h 21mFrontier
Deal found 11/6![Frontier logo]()
$138
This CheapOair deal was found by Cheapflights users on 11/6. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/1212:55 pmPDX - ONT
1 stop25h 30mFrontier
Sun 12/146:15 amONT - PDX
1 stop26h 21mFrontier
Deal found 11/6![Frontier logo]()
$142
This Super.com deal was found by Cheapflights users on 11/6. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/181:26 pmPDX - ONT
1 stop8h 01mFrontier
Mon 11/2412:29 pmONT - PDX
Nonstop2h 35mFrontier
Deal found 11/6![Frontier logo]()
$143
This Frontier deal was found by Cheapflights users on 11/5. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/1512:52 pmPDX - ONT
1 stop10h 58mFrontier
Sun 11/2312:29 pmONT - PDX
Nonstop2h 35mFrontier
Deal found 11/5![Frontier logo]()
$144
This CheapOair deal was found by Cheapflights users on 11/6. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/412:51 pmPDX - ONT
1 stop25h 34mFrontier
Sun 12/75:18 pmONT - PDX
1 stop15h 18mFrontier
Deal found 11/6![Frontier logo]()
$146
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 November 6, 2025.
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
PDX - ONT
PDXONT
Portland
Sat 1/3
9:38 pm-11:59 pm
Nonstop2h 21m
Ontario
Thu 1/8
5:59 pm-8:26 pm
Nonstop2h 27m
$167
PortlandOntario
PDX - ONT
PDXONT
Portland
Tue 12/2
7:30 am-12:17 pm
1 stop4h 47m
Ontario
Sat 12/6
6:41 pm-10:52 pm
1 stop4h 11m
$167
PortlandOntario
PDX - ONT
PDXONT
Portland
Wed 1/7
10:46 am-1:06 pm
Nonstop2h 20m
Ontario
Mon 1/12
5:59 pm-8:26 pm
Nonstop2h 27m
$167
PortlandOntario
PDX - ONT
PDXONT
Portland
Mon 1/5
2:55 pm-5:11 pm
Nonstop2h 16m
Ontario
Sat 1/10
5:59 pm-8:26 pm
Nonstop2h 27m
$167
PortlandOntario
PDX - ONT
PDXONT
Portland
Wed 12/31
2:55 pm-5:11 pm
Nonstop2h 16m
Ontario
Mon 1/5
6:05 pm-8:30 pm
Nonstop2h 25m
$167
PortlandOntario
PDX - ONT
PDXONT
Portland
Fri 12/5
5:30 am-11:13 am
1 stop5h 43m
Ontario
Sat 12/6
6:40 am-1:14 pm
1 stop6h 34m
$177
PortlandOntario
PDX - ONT
PDXONT
Portland
Wed 12/3
7:09 pm-11:58 pm
1 stop4h 49m
Ontario
Mon 12/8
6:00 am-12:15 am
2 stops18h 15m
$182
PortlandOntario
PDX - ONT
PDXONT
Portland
Thu 12/4
5:49 pm-11:29 pm
1 stop5h 40m
Ontario
Sun 12/7
7:10 am-9:41 am
Nonstop2h 31m
$182
PortlandOntario
PDX - ONT
PDXONT
Portland
Wed 1/28
2:43 pm-5:03 pm
Nonstop2h 20m
Ontario
Fri 1/30
4:03 pm-12:38 pm
1 stop20h 35m
$182
PortlandOntario
PDX - ONT
PDXONT
Portland
Tue 12/23
9:38 pm-11:59 pm
Nonstop2h 21m
Ontario
Wed 12/31
7:00 am-9:29 am
Nonstop2h 29m
$187
Showing 1-10 of 21 results
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 November.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy2 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*1 star | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*1 star | |
| Price Accuracy3 stars | Trust Score*2 stars | |
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*1 star | |
| Price Accuracy3 stars | Trust Score*3 stars |
- Most accurate provider: When it comes to deals on Portland-Ontario flights, users find the pricing of CheapOair to be most consistent on Cheapflights vs. CheapOair Users can find the same prices on Portland-Ontario flight deals on Cheapflights vs. CheapOair >95% of the time. Price accuracy is based on data collected from Portland-Ontario flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on Portland-Ontario flights, Cheapflights users trust CheapOair the most. CheapOair 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-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
Prices
Airlines
More
How far ahead should I book a flight from Portland to Ontario?
Use this chart to determine the optimal time to book a round-trip flight from Portland to Ontario. Price data was last updated on October 31, 2025.
The price you pay for your flight from Portland to Ontario may vary depending on when you book. For the best chance of a lower fare, look to book 47 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.
What is the cheapest month to book a flight from Portland to Ontario?
Currently, January is the cheapest month in which you can book a flight from Portland to Ontario (average of $49). Flying from Portland to Ontario in July is currently the most expensive (average of $89). 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 PDX to ONT?
Find hourly flight availability from Portland to Ontario. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated November 6, 2025.
When flying from Portland to Ontario, the time of day you fly usually plays a role in the price. Save by searching for a flight in the morning, which can drop the price by up to 35% versus a flight in the afternoon.
What is the cheapest day to fly from Portland to Ontario?
Use this chart to determine the cheapest time to fly round-trip from Portland to Ontario. Price data was last updated on November 2, 2025.
Travelers seeking maximum savings on their Portland to Ontario flight should consider departing on Friday mornings when fares are most often at their lowest. Monday at noon flights should be avoided if possible as fares are typically the most expensive at this time.
What’s the top layover airport for flights from Portland to Ontario?
Share of 1-stop round-trip flights from Portland to Ontario chosen by Cheapflights users in the past 12 months, using the same layover each way.
Sacramento (SMF) – chosen by Cheapflights users on 88% of 1-stop itineraries from Portland to Ontario on Cheapflights.
What’s the fastest layover option from Portland to Ontario?
Shortest average travel time for 1-stop one-way flights from Portland to Ontario, based on itineraries clicked by Cheapflights users over the past 12 months, grouped by layover airport.
Flights via Sacramento (SMF) have the shortest average one-way travel time for 1-stop routes: 3h 40m.
What’s the fastest layover option from Portland to Ontario?
Shortest average travel time for 1-stop one-way flights from Portland to Ontario, based on itineraries clicked by Cheapflights users over the past 12 months, grouped by layover airport.
Flights via Sacramento (SMF) have the shortest average one-way travel time for 1-stop routes: 3h 40m.
Which airport typically offers the quickest layover for flights from Portland to Ontario?
Average layover duration for 1-stop one-way flights from Portland to Ontario, chosen by Cheapflights users in the last 12 months, grouped by stopover airport.
Flights via San Francisco (SFO) offer the fastest connection on this route, with an average layover time of 0h 42m.
The best insider tips for Portland to Ontario flights
Snippets provided in this section are AI-generated based on a summarization of Cheapflights-commissioned articles. The articles are presented as-is, for general informational purposes only, and may not be up-to-date. The opinions contained in the articles are original to the author and reflect their authentic experience, which may vary significantly from the experience of others.
Cheapflights partnered with top experts to bring you the best recommendations for your Portland to Ontario trip
Airlines
![Frontier]()
Frontier
![Alaska Airlines]()
Alaska Airlines
Alaska Airlines offers 32” legroom in Main Cabin, enhancing comfort on short domestic flights.
Alaska Airlines' Wi-Fi is available for a flat fee, ideal for working during flights.
Airports
Our travel experts
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 November 6, 2025.
Read through reviews of airlines operating flights from Portland to Ontario, such as Alaska Airlines, Southwest, and Delta. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Boarding
8.1
Overall
8.0
Comfort
7.8
Crew
8.5
Food
7.1
Entertainment
7.0
Reviews
1 / 20
6.0
GoodHannah,Aug 2025
SFO - SAN
Boarding
8.1
Overall
8.0
Comfort
7.8
Crew
8.5
Food
7.1
Entertainment
7.0
Reviews
1 / 20
6.0
GoodHannah,Aug 2025
SFO - SAN
Boarding
8.1
Overall
8.0
Comfort
7.8
Crew
8.5
Food
7.1
Entertainment
7.0
Reviews
1 / 20
6.0
GoodHannah,Aug 2025
SFO - SAN
Boarding
8.1
Overall
8.0
Comfort
7.8
Crew
8.5
Food
7.1
Entertainment
7.0
Reviews
1 / 20
6.0
GoodHannah,Aug 2025
SFO - SAN
Boarding
8.1
Overall
8.0
Comfort
7.8
Crew
8.5
Food
7.1
Entertainment
7.0
Reviews
1 / 20
6.0
GoodHannah,Aug 2025
SFO - SAN
Boarding
8.1
Overall
8.0
Comfort
7.8
Crew
8.5
Food
7.1
Entertainment
7.0
Reviews
1 / 20
6.0
GoodHannah,Aug 2025
SFO - SAN
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.
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Alternative routes for Portland to Ontario
See prices for flight routes from nearby airports that may be better suited for you.
Top 6 airlines flying from Portland to Ontario
Discover the top 6 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 November 6, 2025.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$64 | Average$149 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$93 | Average$316 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$98 | Average$238 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$158 | Average$339 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$167 | Average$301 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$173 | Average$279 | FlexibilityNo cancel fee | On-time63% |