$82 Cheap Flights from St. Louis (STL) to Portland (PDX)

View $82 flight on Mon, Sep 15, 2025Opens in a new window

Popular airlines from St. Louis Lambert Intl. Airport (STL) to Portland International Airport (PDX)

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Cheap Flights from St. Louis to Portland (STL-PDX)

Prices were available within the past 7 days and start at $82 for one-way flights and $155 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Southwest Airlines
Sat, Sep 27 - Sat, Oct 4
STL
St. Louis
PDX
Portland
$155 Roundtrip, found 9 hours ago
$155
Roundtrip
found 9 hours ago
Select Southwest Airlines flight, departing Sat, Sep 27 from St. Louis to Portland, returning Sat, Oct 4, priced at $155 found 9 hours ago
Southwest Airlines
Sat, Sep 27 - Sat, Oct 4
STL
St. Louis
PDX
Portland
$164 Roundtrip, found 9 hours ago
$164
Roundtrip
found 9 hours ago
Select Southwest Airlines flight, departing Sat, Sep 27 from St. Louis to Portland, returning Sat, Oct 4, priced at $164 found 9 hours ago
Southwest Airlines
Sat, Sep 27 - Mon, Sep 29
STL
St. Louis
PDX
Portland
$164 Roundtrip, found 16 hours ago
$164
Roundtrip
found 16 hours ago
Select Southwest Airlines flight, departing Sat, Sep 27 from St. Louis to Portland, returning Mon, Sep 29, priced at $164 found 16 hours ago
Southwest Airlines
Sat, Sep 27 - Sat, Oct 4
STL
St. Louis
PDX
Portland
$169 Roundtrip, found 9 hours ago
$169
Roundtrip
found 9 hours ago
Select Southwest Airlines flight, departing Sat, Sep 27 from St. Louis to Portland, returning Sat, Oct 4, priced at $169 found 9 hours ago
Southwest Airlines
Sat, Sep 27 - Sat, Oct 4
STL
St. Louis
PDX
Portland
$169 Roundtrip, found 9 hours ago
$169
Roundtrip
found 9 hours ago
Select Southwest Airlines flight, departing Sat, Sep 27 from St. Louis to Portland, returning Sat, Oct 4, priced at $169 found 9 hours ago
Delta
Tue, Aug 26 - Sat, Aug 30
STL
St. Louis
PDX
Portland
$171 Roundtrip, found 2 days ago
$171
Roundtrip
found 2 days ago
Select Delta flight, departing Tue, Aug 26 from St. Louis to Portland, returning Sat, Aug 30, priced at $171 found 2 days ago
Southwest Airlines
Thu, Oct 30 - Mon, Nov 3
STL
St. Louis
PDX
Portland
$173 Roundtrip, found 5 hours ago
$173
Roundtrip
found 5 hours ago
Select Southwest Airlines flight, departing Thu, Oct 30 from St. Louis to Portland, returning Mon, Nov 3, priced at $173 found 5 hours ago
American Airlines
Thu, Oct 30 - Mon, Nov 3
STL
St. Louis
PDX
Portland
$173 Roundtrip, found 5 hours ago
$173
Roundtrip
found 5 hours ago
Select American Airlines flight, departing Thu, Oct 30 from St. Louis to Portland, returning Mon, Nov 3, priced at $173 found 5 hours ago
Alaska Airlines
Thu, Oct 30 - Mon, Nov 3
STL
St. Louis
PDX
Portland
$181 Roundtrip, found 5 hours ago
$181
Roundtrip
found 5 hours ago
Select Alaska Airlines flight, departing Thu, Oct 30 from St. Louis to Portland, returning Mon, Nov 3, priced at $181 found 5 hours ago
Hawaiian Airlines
Sat, Aug 30 - Mon, Sep 15
STL
St. Louis
PDX
Portland
$181 Roundtrip, found 1 day ago
$181
Roundtrip
found 1 day ago
Select Hawaiian Airlines flight, departing Sat, Aug 30 from St. Louis to Portland, returning Mon, Sep 15, priced at $181 found 1 day ago

Find the cheapest month to fly from St. Louis (STL) to Portland (PDX)

September is typically the cheapest month to fly

From $118 - $296 per traveler.

Graph displaying average flight prices per month

Flights from St. Louis (STL) to Portland (PDX)
Origin airport
Lambert-St. Louis Intl.
Destination airport
Portland Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Hawaiian Airlines, Southwest Airlines, United
Roundtrip price
$154
Distance
1703 mi
Average flight time
3 hours 50 mins

St. Louis to Portland Flights

The cheapest times to fly from St. Louis to Portland

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from St. Louis to Portland are during the month of September. You can find some of the cheapest flights from St. Louis to Portland with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from St. Louis to Portland

Sunday is one of the best days to book for cheap flights from St. Louis to Portland: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from St. Louis to Portland

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from St. Louis to Portland in 2025. You can also book with separate airlines for your outbound and return journeys, from $82 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap St. Louis to Portland flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your St. Louis to Portland airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

Frequently asked questions

How much does a flight from Lambert-St. Louis Intl. Airport (STL) to Portland Intl. Airport (PDX) cost?
Cheap round-trip fares from Lambert-St. Louis Intl. Airport (STL) to Portland Intl. Airport (PDX) start from $359. This information is based on the cheapest price found on Expedia for this return journey departing within the next three months. This airfare is for a Southwest Airlines flight leaving STL on July 20 2025 and touching down at PDX. The price was last updated on July 8 2025 and has not changed since.
What is the cheapest month to fly from STL to PDX?
The cheapest flights from STL to PDX are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
What is the cheapest airline that flies from STL to PDX?
With fares starting at $180 for a one-way flight from STL to PDX, Southwest Airlines is currently the cheapest carrier flying this route. This fare is based on the lowest price found on Expedia departing within the next three months. The flight takes off from STL on August 30 2025. Prices were last updated on July 8 2025 and have not changed since.
How many flights per day from Lambert-St. Louis Intl. Airport (STL) to Portland Intl. Airport (PDX)?
Direct flights from Lambert-St. Louis Intl. Airport (STL) to Portland Intl. Airport (PDX) aren't available daily, so you'll have to take a flight with a layover. Explore your options with Expedia's filters. Enter your dates and select either "1 Stop" or "2+ Stops."
What day of the week has the most flights from STL to PDX?
Typically you'll find the most flight options available on a Friday. Tuesdays are often the quietest.* However, this can vary based on the airline, season and other factors.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What airline has the least delays from STL to PDX?
Southwest Airlines has the best performance for on-time direct flights from Lambert-St. Louis Intl. Airport (STL) to Portland Intl. Airport (PDX), with an on-time rating of 80%. Use the Expedia App to look up your flight status before you go and get real-time updates about any trip changes.
What is the best time to fly from Lambert-St. Louis Intl. Airport (STL) to Portland Intl. Airport (PDX)?
To touch down at Portland Intl. Airport (PDX) without delays, pick a flight that leaves Lambert-St. Louis Intl. Airport (STL) before 3 PM. The likelihood of cancellations is 22% higher, on average, for departures after this time.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
Is it cheaper to buy a plane ticket from Lambert-St. Louis Intl. Airport (STL) to Portland Intl. Airport (PDX) last-minute?
Last-minute bookings from STL to PDX are typically more expensive. For the lowest prices, start searching for flights well in advance. That said, if you're flexible with your travel dates, you may score a cheap fare right before your trip.
Is it cheaper to book a STL to PDX flight and hotel package?
You can save money by booking a STL to PDX flight and hotel package compared to booking separately. In fact, travelers could save hundreds of dollars by bundling with Expedia. And it's easy to manage it all in one convenient place. After selecting your preferred accommodations and flights, consider adding extras including car rentals, activities and tours.
Can I cancel or change the date of my flight from Lambert-St. Louis Intl. Airport (STL) to Portland Intl. Airport (PDX)?
If you booked your STL to PDX flight in the last 24 hours, you may be able to cancel or modify it at no cost. Depending on the airline and the ticket type you purchased, additional charges may apply for changes after that time. Airline policies and contact information can be found in your itinerary or confirmation email. Or, visit our Customer Service portal for more details.

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*Available to One Key members.