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.

Most accurate provider | CheapOair 3 stars |
|---|---|
Most trusted provider | CheapOair 3 stars |
Round-trip from | $159 (Trip.com) |
One-way from | $93 (American Airlines) |
Popular in | March |
Cheapest in | July |
Average price | $277 |
Good round-trip deal | $181 or less |
Good one-way deal | $104 or less |
Fly from
Fly to
Route
Depart
Return
Price
PortlandOntario
PDX - ONT
PDXONT
Portland
Tue 1/6
5:05 am-12:25 pm
2 stops7h 20m
Ontario
Sat 1/10
3:30 pm-7:30 pm
1 stop4h 00m
PortlandOntario
PDX - ONT
PDXONT
Portland
Wed 1/28
5:15 pm-10:51 pm
1 stop5h 36m
Ontario
Sun 2/1
3:30 pm-8:59 pm
1 stop5h 29m
PortlandOntario
PDX - ONT
PDXONT
Portland
Tue 1/13
5:50 pm-8:10 pm
Nonstop2h 20m
Ontario
Wed 1/14
4:03 pm-8:47 pm
1 stop4h 44m
PortlandOntario
PDX - ONT
PDXONT
Portland
Fri 1/9
10:46 am-1:06 pm
Nonstop2h 20m
Ontario
Tue 1/13
1:46 pm-4:20 pm
Nonstop2h 34m
PortlandOntario
PDX - ONT
PDXONT
Portland
Wed 1/7
9:55 am-5:10 pm
2 stops7h 15m
Ontario
Sun 1/11
3:50 pm-11:00 pm
1 stop7h 10m
PortlandOntario
PDX - ONT
PDXONT
Portland
Sat 1/17
2:43 pm-5:03 pm
Nonstop2h 20m
Ontario
Tue 1/20
5:59 pm-8:26 pm
Nonstop2h 27m
PortlandOntario
PDX - ONT
PDXONT
Portland
Wed 1/7
2:41 pm-7:16 pm
1 stop4h 35m
Ontario
Fri 1/9
4:03 pm-10:46 pm
1 stop6h 43m
PortlandOntario
PDX - ONT
PDXONT
Portland
Wed 1/7
2:41 pm-7:16 pm
1 stop4h 35m
Ontario
Thu 1/8
4:03 pm-10:46 pm
1 stop6h 43m
PortlandOntario
PDX - ONT
PDXONT
Portland
Thu 1/1
2:55 pm-5:11 pm
Nonstop2h 16m
Ontario
Fri 1/9
7:00 am-9:33 am
Nonstop2h 33m
PortlandOntario
PDX - ONT
PDXONT
Portland
Tue 1/6
5:10 am-9:50 am
1 stop4h 40m
Ontario
Thu 1/8
5:59 pm-8:26 pm
Nonstop2h 27m
| 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 |
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.
Currently, January is the cheapest month in which you can book a flight from Portland to Ontario (average of $48). Flying from Portland to Ontario in November is currently the most expensive (average of $92). 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.
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 at noon.
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.
Sacramento (SMF) – chosen by Cheapflights users on 88% of 1-stop itineraries from Portland to Ontario on Cheapflights.
Sacramento (SMF) is the most affordable 1-stop option, with an average round-trip price of $270.
Flights via Sacramento (SMF) have the shortest average one-way travel time for 1-stop routes: 3h 40m.
Flights via San Francisco (SFO) offer the fastest connection on this route, with an average layover time of 0h 42m.
Overall
Boarding
Food
Entertainment
Comfort
Crew
Reviews
Hannah,Aug 2025
SFO - SAN
Overall
Boarding
Food
Entertainment
Comfort
Crew
Reviews
Hannah,Aug 2025
SFO - SAN
Overall
Boarding
Food
Entertainment
Comfort
Crew
Reviews
Hannah,Aug 2025
SFO - SAN
Overall
Boarding
Food
Entertainment
Comfort
Crew
Reviews
Hannah,Aug 2025
SFO - SAN
Overall
Boarding
Food
Entertainment
Comfort
Crew
Reviews
Hannah,Aug 2025
SFO - SAN
Overall
Boarding
Food
Entertainment
Comfort
Crew
Reviews
Hannah,Aug 2025
SFO - SAN
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$63 | Average$149 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$83 | Average$277 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$98 | Average$238 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$167 | Average$298 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$173 | Average$280 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$183 | Average$346 | FlexibilityNo cancel fee | On-time69% |