$113 Cheap Flights from Portland (PDX) to St. Louis (STL)

View $113 flight on Thu, Sep 11, 2025Opens in a new window

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

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

Prices were available within the past 7 days and start at $113 for one-way flights and $158 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Southwest Airlines
Thu, Sep 4 - Wed, Sep 10
PDX
Portland
STL
St. Louis
$158 Roundtrip, found 3 days ago
$158
Roundtrip
found 3 days ago
Select Southwest Airlines flight, departing Thu, Sep 4 from Portland to St. Louis, returning Wed, Sep 10, priced at $158 found 3 days ago
American Airlines
Thu, Sep 4 - Wed, Sep 10
PDX
Portland
STL
St. Louis
$159 Roundtrip, found 3 days ago
$159
Roundtrip
found 3 days ago
Select American Airlines flight, departing Thu, Sep 4 from Portland to St. Louis, returning Wed, Sep 10, priced at $159 found 3 days ago
Alaska Airlines
Mon, Nov 17 - Wed, Nov 19
PDX
Portland
STL
St. Louis
$175 Roundtrip, found 3 days ago
$175
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Mon, Nov 17 from Portland to St. Louis, returning Wed, Nov 19, priced at $175 found 3 days ago
Southwest Airlines
Thu, Sep 4 - Wed, Sep 10
PDX
Portland
STL
St. Louis
$182 Roundtrip, found 3 days ago
$182
Roundtrip
found 3 days ago
Select Southwest Airlines flight, departing Thu, Sep 4 from Portland to St. Louis, returning Wed, Sep 10, priced at $182 found 3 days ago
Hawaiian Airlines
Fri, Sep 5 - Thu, Sep 18
PDX
Portland
STL
St. Louis
$193 Roundtrip, found 5 days ago
$193
Roundtrip
found 5 days ago
Select Hawaiian Airlines flight, departing Fri, Sep 5 from Portland to St. Louis, returning Thu, Sep 18, priced at $193 found 5 days ago
American Airlines
Sun, Aug 31 - Sun, Sep 7
PDX
Portland
STL
St. Louis
$193 Roundtrip, found 5 days ago
$193
Roundtrip
found 5 days ago
Select American Airlines flight, departing Sun, Aug 31 from Portland to St. Louis, returning Sun, Sep 7, priced at $193 found 5 days ago
Southwest Airlines
Mon, Nov 17 - Wed, Nov 19
PDX
Portland
STL
St. Louis
$197 Roundtrip, found 3 days ago
$197
Roundtrip
found 3 days ago
Select Southwest Airlines flight, departing Mon, Nov 17 from Portland to St. Louis, returning Wed, Nov 19, priced at $197 found 3 days ago
Southwest Airlines
Tue, Oct 28 - Mon, Nov 3
PDX
Portland
STL
St. Louis
$199 Roundtrip, found 5 days ago
$199
Roundtrip
found 5 days ago
Select Southwest Airlines flight, departing Tue, Oct 28 from Portland to St. Louis, returning Mon, Nov 3, priced at $199 found 5 days ago
Alaska Airlines
Mon, Nov 17 - Wed, Nov 19
PDX
Portland
STL
St. Louis
$201 Roundtrip, found 3 days ago
$201
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Mon, Nov 17 from Portland to St. Louis, returning Wed, Nov 19, priced at $201 found 3 days ago
United
Sat, Oct 25 - Fri, Oct 31
PDX
Portland
STL
St. Louis
$222 Roundtrip, found 10 hours ago
$222
Roundtrip
found 10 hours ago
Select United flight, departing Sat, Oct 25 from Portland to St. Louis, returning Fri, Oct 31, priced at $222 found 10 hours ago

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

September is typically the cheapest month to fly

From $118 - $303 per traveler.

Graph displaying average flight prices per month

Alternative airports near St. Louis

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Lambert-St. Louis Intl. STL. Cheapest option available. Average driving time to city center is 20 minutes. Flights from $350
STL
Lambert-St. Louis Intl.
Cheapest
Average driving time to city center20 min
Flights from $350
Flights from Portland (PDX) to St. Louis (STL)
Origin airport
Portland Intl.
Destination airport
Lambert-St. Louis Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Southwest Airlines, United
Roundtrip price
$158
Distance
1703 mi

Portland to St. Louis Flights

The cheapest times to fly from Portland to St. Louis

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 Portland to St. Louis are during the month of September. You can find some of the cheapest flights from Portland to St. Louis with Expedia's search tool and vast selection of airlines.

 

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

Sunday is one of the best days to book for cheap flights from Portland to St. Louis: 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 Portland to St. Louis

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 Portland to St. Louis in 2025. You can also book with separate airlines for your outbound and return journeys, from $113 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 Portland to St. Louis 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 Portland to St. Louis 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 Portland Intl. Airport (PDX) to Lambert-St. Louis Intl. Airport (STL) cost?
Get a cheap one-way flight from $113 or cheap return flight from $158 from Portland Intl. Airport (PDX) to Lambert-St. Louis Intl. Airport (STL) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to see our cheapest flight deals on this route.
What is the cheapest month to fly from Portland Intl. Airport (PDX) to Lambert-St. Louis Intl. Airport (STL)?
The cheapest month to fly from PDX to STL is September, when demand is low. Off-peak months are often when you'll find cheap fares for travel between these airports.
What is the cheapest airline that flies from Portland Intl. Airport (PDX) to Lambert-St. Louis Intl. Airport (STL)?
To find the cheapest airline that'll fly you from PDX to STL, use Expedia's filter tool. Tailor your search based on what's important to you, such as preferred carriers and flight duration. You can then sort your results by "Price (lowest to highest)" to discover the cheapest flight right away.
How many flights per day from Portland Intl. Airport (PDX) to Lambert-St. Louis Intl. Airport (STL)?
Nonstop flights from Portland Intl. Airport (PDX) to Lambert-St. Louis Intl. Airport (STL) aren't available daily, so you'll need to take a flight with a layover. Explore your options with Expedia's filter tool. Enter your dates and click on either "1 Stop" or "2+ Stops."
What day of the week has the most flights from PDX to STL?
Friday is usually the busiest day for flights, while Tuesday tends to be the quietest.* Remember that flight schedules can change depending on a range of factors, including the carrier and season.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What airline has the least delays from PDX to STL?
Consider traveling with Sun Country Airlines if you'd like to go straight from Portland Intl. Airport (PDX) to Lambert-St. Louis Intl. Airport (STL) without any delays. This airline has the best track record for punctuality, with an on-time performance of 100%. Want to be notified if anything changes? You can keep an eye on your flight status using the Expedia App.
What is the best time to fly from Portland Intl. Airport (PDX) to Lambert-St. Louis Intl. Airport (STL)?
To avoid potential delays on the Portland Intl. Airport (PDX) to Lambert-St. Louis Intl. Airport (STL) route, aim to fly before 3 PM. Departures after this hour have a 22% higher chance of being canceled.**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 Portland Intl. Airport (PDX) to Lambert-St. Louis Intl. Airport (STL) last-minute?
Last-minute bookings from PDX to STL are usually more expensive. To secure the best rates, start searching for flights as early as possible. That said, if you can play around with your travel dates, it's possible to find a cheap ticket right before your trip.
Is it cheaper to book a PDX to STL flight and hotel package?
You'll generally save money by booking a PDX to STL 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. Once you've selected your preferred accommodations and flights, consider other add-ons like car rentals, tours and activities.
Can I cancel or change the date of my flight from Portland Intl. Airport (PDX) to Lambert-St. Louis Intl. Airport (STL)?
If you booked your PDX to STL flight within the last 24 hours, you may be able to cancel or modify it without any fees. Depending on the airline and the fare 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, go to our Customer Service portal for more information.

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*Available to One Key members.