$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 11/26. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — ONT
Sep 14 — Sep 211
Round-trip
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
Best
Last-minute
One-way
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 August 15, 2026.
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 August 15, 2026.
This Delta deal was found by Cheapflights users on 8/13. 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 11/114:40 pm -
2 stops10h 18m
Wed 11/1812:22 pm -
1 stop8h 11m
Deal found 8/13![Delta logo]()
$302
This Delta deal was found by Cheapflights users on 8/10. 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 12/1612:50 pm -
2 stops14h 08m
Wed 1/66:00 am -
2 stops13h 23m
Deal found 8/10![Delta logo]()
$307
This Delta deal was found by Cheapflights users on 8/11. 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.
Fri 9/42:14 pm -
1 stop10h 38m
Sun 9/66:00 am -
2 stops12h 31m
Deal found 8/11![Delta logo]()
$333
This United Airlines deal was found by Cheapflights users on 8/11. 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.
Fri 9/114:57 pm -
1 stop9h 02m
Wed 9/166:08 am -
2 stops10h 16m
Deal found 8/11![United Airlines logo]()
$334
This American Airlines deal was found by Cheapflights users on 8/12. 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 10/214:30 pm -
1 stop9h 29m
Thu 10/2910:10 pm -
1 stop10h 16m
Deal found 8/12![American Airlines logo]()
$348
This United Airlines deal was found by Cheapflights users on 8/11. 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.
Fri 9/45:03 pm -
1 stop8h 32m
Sun 9/65:00 am -
1 stop7h 51m
Deal found 8/11![United Airlines logo]()
$362
This Southwest deal was found by Cheapflights users on 8/12. 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.
Sat 9/265:40 am -
2 stops11h 35m
Wed 9/309:40 am -
2 stops9h 30m
Deal found 8/12![Southwest logo]()
$369
This American Airlines deal was found by Cheapflights users on 8/11. 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.
Fri 9/49:52 am -
2 stops11h 55m
Sun 9/610:00 am -
2 stops9h 48m
Deal found 8/11![American Airlines logo]()
$370
This United Airlines deal was found by Cheapflights users on 8/13. 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.
Fri 8/285:03 pm -
1 stop8h 32m
Tue 9/15:00 am -
2 stops13h 23m
Deal found 8/13![United Airlines logo]()
$374
This American Airlines deal was found by Cheapflights users on 8/13. 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.
Fri 8/281:30 pm -
2 stops12h 29m
Tue 9/16:00 am -
2 stops12h 21m
Deal found 8/13![American Airlines logo]()
$380
Best flights from Portland to OntarioDiscover 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 August 15, 2026.
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 August 15, 2026.
This Delta deal was found by Cheapflights users on 8/13. 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 11/114:40 pm -
2 stops10h 18m
Wed 11/1812:22 pm -
1 stop8h 11m
Deal found 8/13![Delta logo]()
$302
This United Airlines deal was found by Cheapflights users on 8/11. 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.
Fri 9/114:57 pm -
1 stop9h 02m
Wed 9/166:08 am -
2 stops10h 16m
Deal found 8/11![United Airlines logo]()
$334
This United Airlines deal was found by Cheapflights users on 8/11. 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.
Fri 9/45:03 pm -
1 stop8h 32m
Sun 9/65:00 am -
1 stop7h 51m
Deal found 8/11![United Airlines logo]()
$362
This United Airlines deal was found by Cheapflights users on 8/13. 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 11/113:23 pm -
1 stop8h 28m
Wed 11/185:00 am -
1 stop8h 02m
Deal found 8/13![United Airlines logo]()
$407
This United Airlines deal was found by Cheapflights users on 8/13. 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 11/113:23 pm -
1 stop8h 28m
Sat 11/145:00 am -
1 stop8h 02m
Deal found 8/13![United Airlines logo]()
$407
This United Airlines deal was found by Cheapflights users on 8/13. 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 11/43:23 pm -
1 stop8h 28m
Tue 11/105:00 am -
1 stop8h 02m
Deal found 8/13![United Airlines logo]()
$440
Last-minute flights from Portland to OntarioDiscover last-minute flight deals from Portland to Ontario. Data last updated August 15, 2026 and is based on user searches.
Discover last-minute flight deals from Portland to Ontario. Data last updated August 15, 2026 and is based on user searches.
This United Airlines deal was found by Cheapflights users on 8/13. 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.
Fri 8/285:03 pm -
1 stop8h 32m
Tue 9/15:00 am -
2 stops13h 23m
Deal found 8/13![United Airlines logo]()
$374
This American Airlines deal was found by Cheapflights users on 8/13. 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.
Fri 8/281:30 pm -
2 stops12h 29m
Tue 9/16:00 am -
2 stops12h 21m
Deal found 8/13![American Airlines logo]()
$380
This Delta deal was found by Cheapflights users on 8/11. 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.
Fri 9/42:14 pm -
1 stop10h 38m
Sun 9/66:00 am -
2 stops12h 31m
Deal found 8/11![Delta logo]()
$333
This United Airlines deal was found by Cheapflights users on 8/11. 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.
Fri 9/45:03 pm -
1 stop8h 32m
Sun 9/65:00 am -
1 stop7h 51m
Deal found 8/11![United Airlines logo]()
$362
This American Airlines deal was found by Cheapflights users on 8/11. 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.
Fri 9/49:52 am -
2 stops11h 55m
Sun 9/610:00 am -
2 stops9h 48m
Deal found 8/11![American Airlines logo]()
$370
This United Airlines deal was found by Cheapflights users on 8/11. 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.
Fri 9/114:57 pm -
1 stop9h 02m
Wed 9/166:08 am -
2 stops10h 16m
Deal found 8/11![United Airlines logo]()
$334
This Southwest deal was found by Cheapflights users on 8/14. 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.
Fri 9/115:55 am -
2 stops11h 05m
Mon 9/148:40 pm -
2 stops10h 15m
Deal found 8/14![Southwest logo]()
$399
This American Airlines deal was found by Cheapflights users on 8/12. 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 9/237:32 am -
2 stops13h 45m
Sun 9/277:11 pm -
2 stops14h 54m
Deal found 8/12![American Airlines logo]()
$417
This Southwest deal was found by Cheapflights users on 8/12. 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.
Sat 9/265:40 am -
2 stops11h 35m
Wed 9/309:40 am -
2 stops9h 30m
Deal found 8/12![Southwest logo]()
$369
This Delta deal was found by Cheapflights users on 8/10. 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.
Tue 9/296:00 am -
1 stop8h 05m
Fri 10/2312:18 pm -
1 stop8h 17m
Deal found 8/10![Delta logo]()
$418
One-way flights from Portland to OntarioSearch for one-way flight options from Portland to Ontario. Find affordable one-way fares based on user searches. Data last updated August 15, 2026.
Search for one-way flight options from Portland to Ontario. Find affordable one-way fares based on user searches. Data last updated August 15, 2026.
This United Airlines deal was found by Cheapflights users on 8/13. 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 11/268:08 am -
1 stop10h 51m
Deal found 8/13![United Airlines logo]()
$149
This Kiwi.com deal was found by Cheapflights users on 8/14. 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.
Wed 9/237:00 am -
2 stops30h 30m
Deal found 8/14![Multiple Airlines logo]()
$173
This JetBlue deal was found by Cheapflights users on 8/14. 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 JetBlue is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/52:40 pm -
1 stop10h 19m
Deal found 8/14![JetBlue logo]()
$180
This United Airlines deal was found by Cheapflights users on 8/14. 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 9/108:00 am -
2 stops13h 11m
Deal found 8/14![United Airlines logo]()
$185
This Kiwi.com deal was found by Cheapflights users on 8/14. 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.
Fri 9/116:00 am -
2 stops37h 34m
Deal found 8/14![Multiple Airlines logo]()
$200
This United Airlines deal was found by Cheapflights users on 8/13. 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.
Sat 9/55:03 pm -
1 stop8h 32m
Deal found 8/13![United Airlines logo]()
$204
This American Airlines deal was found by Cheapflights users on 8/11. 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.
Sun 9/68:00 am -
2 stops14h 15m
Deal found 8/11![American Airlines logo]()
$221
This Delta deal was found by Cheapflights users on 8/14. 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 9/96:00 am -
1 stop8h 05m
Deal found 8/14![Delta logo]()
$230
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 August 15, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $302 (Delta) |
One-way from | $149 (United Airlines) |
Popular in | April |
Cheapest in | February |
Average price | $419 |
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 August 15, 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
Cheapest round-trip
PortlandOntario
PWM Portland - ONT Ontario
PWMONT
Portland
Wed 11/11
4:40 pm-11:58 pm
2 stops10h 18m
Ontario
Wed 11/18
12:22 pm-11:33 pm
1 stop8h 11m
$302
PortlandOntario
PWM Portland - ONT Ontario
PWMONT
Portland
Fri 9/11
4:57 pm-10:59 pm
1 stop9h 02m
Ontario
Wed 9/16
6:08 am-7:24 pm
2 stops10h 16m
$334
Quickest round-trip
PortlandOntario
PWM Portland - ONT Ontario
PWMONT
Portland
Fri 9/4
5:03 pm-10:35 pm
1 stop8h 32m
Ontario
Sun 9/6
5:00 am-3:51 pm
1 stop7h 51m
$362
PortlandOntario
PWM Portland - ONT Ontario
PWMONT
Portland
Wed 11/11
3:23 pm-8:51 pm
1 stop8h 28m
Ontario
Wed 11/18
5:00 am-4:02 pm
1 stop8h 02m
$407
PortlandOntario
PWM Portland - ONT Ontario
PWMONT
Portland
Wed 11/11
3:23 pm-8:51 pm
1 stop8h 28m
Ontario
Sat 11/14
5:00 am-4:02 pm
1 stop8h 02m
$407
PortlandOntario
PWM Portland - ONT Ontario
PWMONT
Portland
Wed 11/4
3:23 pm-8:51 pm
1 stop8h 28m
Ontario
Tue 11/10
5:00 am-4:02 pm
1 stop8h 02m
$440
Cheapest one-way
PortlandOntario
PWM Portland - ONT Ontario
PWMONT
Portland
Thu 11/26
5:50 am-3:59 pm
2 stops13h 09m
$154
PortlandOntario
PWM Portland - ONT Ontario
PWMONT
Portland
Sat 9/5
5:03 pm-10:35 pm
1 stop8h 32m
$204
PortlandOntario
PWM Portland - ONT Ontario
PWMONT
Portland
Tue 9/1
7:35 am-6:11 pm
2 stops13h 36m
$209
PortlandOntario
PWM Portland - ONT Ontario
PWMONT
Portland
Fri 9/11
4:57 pm-10:59 pm
1 stop9h 02m
$235
Showing 1-10 of 16 resultsSorted by cheapest first
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 August.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars |
- 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.
PWM-ONT
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
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 August 15, 2026.
Read reviews from past customers who have flown 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.
Food
6.4
Entertainment
6.8
Comfort
7.2
Crew
7.9
Boarding
7.5
Overall
7.1
Reviews
1 / 20
2.0
MediocreAnonymous,Mar 2026
MIA - SFO
Food
6.4
Entertainment
6.8
Comfort
7.2
Crew
7.9
Boarding
7.5
Overall
7.1
Reviews
1 / 20
2.0
MediocreAnonymous,Mar 2026
MIA - SFO
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.
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
Complete your trip
Flights by cabin class
Ontario flight routes
Other flight options
Other flights from Portland
Popular flights
Alternative routes for Portland to Ontario
See prices for flight routes from nearby airports that may be better suited for you.
Complete your trip
Complete your trip to Ontario by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Portland to Ontario by cabin class
Find flights from Portland to Ontario, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Other flights to Ontario
Explore flights to Ontario departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on August 15, 2026.
Portland and Ontario flights
Browse other Portland and Ontario flight options. Last updated on August 15, 2026.
Other flights from Portland
Browse through other flights departing from Portland. Flights are based on user searches made on Cheapflights and were last updated on August 15, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Top airline flying from Portland to Ontario
Discover the top airline 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 August 15, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$360 | Average$456 | FlexibilityNo cancel fee | On-time71% |