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$159 Cheap Flights from Portland (PDX) to St. Louis (STL)

View $159 flight on Tue, Sep 15, 2026Opens 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 $159 for one-way flights and $240 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frontier Airlines
Sun, Sep 13 - Wed, Sep 30
PDX
Portland
STL
St. Louis
$240 Roundtrip, found 16 hours ago
$240
Roundtrip
found 16 hours ago
Select Frontier Airlines flight, departing Sun, Sep 13 from Portland to St. Louis, returning Wed, Sep 30, priced at $240 found 16 hours ago
Frontier Airlines
Sun, Sep 13 - Sat, Oct 3
PDX
Portland
STL
St. Louis
$259 Roundtrip, found 16 hours ago
$259
Roundtrip
found 16 hours ago
Select Frontier Airlines flight, departing Sun, Sep 13 from Portland to St. Louis, returning Sat, Oct 3, priced at $259 found 16 hours ago
Frontier Airlines
Sun, Sep 13 - Sat, Sep 26
PDX
Portland
STL
St. Louis
$290 Roundtrip, found 16 hours ago
$290
Roundtrip
found 16 hours ago
Select Frontier Airlines flight, departing Sun, Sep 13 from Portland to St. Louis, returning Sat, Sep 26, priced at $290 found 16 hours ago
Frontier Airlines
Thu, Sep 17 - Sat, Oct 3
PDX
Portland
STL
St. Louis
$309 Roundtrip, found 16 hours ago
$309
Roundtrip
found 16 hours ago
Select Frontier Airlines flight, departing Thu, Sep 17 from Portland to St. Louis, returning Sat, Oct 3, priced at $309 found 16 hours ago
Alaska Airlines
Sat, Sep 19 - Sat, Sep 26
PDX
Portland
STL
St. Louis
$317 Roundtrip, found 3 hours ago
$317
Roundtrip
found 3 hours ago
Select Alaska Airlines flight, departing Sat, Sep 19 from Portland to St. Louis, returning Sat, Sep 26, priced at $317 found 3 hours ago
Southwest Airlines
Sat, Sep 5 - Sat, Sep 12
PDX
Portland
STL
St. Louis
$323 Roundtrip, found 5 hours ago
$323
Roundtrip
found 5 hours ago
Select Southwest Airlines flight, departing Sat, Sep 5 from Portland to St. Louis, returning Sat, Sep 12, priced at $323 found 5 hours ago
Alaska Airlines
Tue, Sep 29 - Tue, Oct 6
PDX
Portland
STL
St. Louis
$327 Roundtrip, found 3 hours ago
$327
Roundtrip
found 3 hours ago
Select Alaska Airlines flight, departing Tue, Sep 29 from Portland to St. Louis, returning Tue, Oct 6, priced at $327 found 3 hours ago
United
Tue, Sep 29 - Wed, Sep 30
PDX
Portland
STL
St. Louis
$332 Roundtrip, found 20 hours ago
$332
Roundtrip
found 20 hours ago
Select United flight, departing Tue, Sep 29 from Portland to St. Louis, returning Wed, Sep 30, priced at $332 found 20 hours ago
Southwest Airlines
Wed, Sep 23 - Sun, Sep 27
PDX
Portland
STL
St. Louis
$333 Roundtrip, just found
$333
Roundtrip
just found
Select Southwest Airlines flight, departing Wed, Sep 23 from Portland to St. Louis, returning Sun, Sep 27, priced at $333 just found
American Airlines
Sat, Sep 5 - Tue, Sep 8
PDX
Portland
STL
St. Louis
$335 Roundtrip, found 19 hours ago
$335
Roundtrip
found 19 hours ago
Select American Airlines flight, departing Sat, Sep 5 from Portland to St. Louis, returning Tue, Sep 8, priced at $335 found 19 hours ago

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 $368
STL
Lambert-St. Louis Intl.
Cheapest
Average driving time to city center20 min
Flights from $368

What you need to know for your flight from Portland Intl. to Lambert-St. Louis Intl.

Portland (PDX) to St. Louis (STL) at a glance

Explore a range of airlines offering flights from Portland International Airport (PDX) to Lambert-St. Louis International Airport (STL) on this short domestic route. Whether you prefer full-service or budget airlines, you can compare various options to find the travel itinerary that aligns with your budget and schedule. Get ready to experience the iconic attractions and vibrant neighborhoods of St. Louis while planning your journey from Portland to St. Louis.

  • Fastest flight duration: around 3h 45m non-stop
  • Route distance: roughly 1,700 miles (2,740 km)
  • Flights per week: around 25+ flights with multiple daily departures on average
  • Typical fares (one-way): economy tickets often range from $110–$375, depending on seasonality and how far ahead you book

Flights from Portland International Airport (PDX) to Lambert-St. Louis International Airport (STL)

Based on recent traveler bookings, here are the top airlines flying from Portland to St. Louis, favored for both one-stop and non-stop flights. Popular layover options include Denver International Airport (DEN) with about a 1-hour layover, Salt Lake City International Airport (SLC) also with a 1-hour layover, and O'Hare International Airport (ORD), which offers a layover of approximately 1 hour and 15 minutes. These choices provide you with the flexibility to compare prices, total travel times, and cabin classes to find the ideal itinerary.

  • Delta: This full-service airline provides convenient one-stop options, with one-way prices typically between $110 and $435. Delta handles about 25% of flights on this route, featuring an in-flight duration of 5 hours and a total travel time of approximately 6 hours and 30 minutes, including layovers.
  • United: As a full-service airline, United offers both non-stop and one-stop services, with fares generally ranging from $115 to $435 for one-way trips. Approximately 23% of departures on this route are operated by United, with an in-air time of around 5 hours and a total journey duration of about 6 hours and 30 minutes.
  • American Airlines: This full-service carrier provides one-stop services, with one-way tickets priced between $110 and $345. Accounting for roughly 23% of departures on this route, American Airlines has a flight time of 5 hours and a full travel duration of about 6 hours and 30 minutes, including any layovers.
  • Southwest Airlines: Known as a low-cost carrier, Southwest offers both non-stop and one-stop flights, with one-way fares typically ranging from $115 to $445. They represent approximately 16% of departures on this route, featuring a standard flight time of 5 hours and a total travel time of about 6 hours and 30 minutes.
  • Alaska Airlines: This full-service airline offers one-stop options with one-way fares usually falling between $115 and $480. Alaska Airlines accounts for about 11% of departures on this route, with a 5-hour in-flight duration and a total journey time of approximately 6 hours and 30 minutes, including layovers.

Travelers flying from Portland to St. Louis have the option to upgrade their flight. Delta provides both first class and premium economy cabins, while United features first class service.

Best time to fly from Portland (PDX) to St. Louis (STL)

The most popular months for travelers flying from Portland to St. Louis are March, April, and June, when peak temperatures in St. Louis reach up to 76.1°F in June. If you prefer quieter travel, consider February, the least busy and relatively cheaper time to visit with fewer crowds and temperatures around 34.9°F. For better deals, May usually offers the lowest average one-way fare around $194. Flight availability peaks in June, with approximately 38 flights per week, making it easier to find convenient departure times. January has the fewest flights, with approximately 18 flights per week.

  • Cheapest time to fly: May usually offers good deals with average one-way fare around $194, roughly 12% cheaper than the yearly average.
  • More budget-friendly months to fly: September, February, and October typically offer average one-way fares roughly ranging from $198 to $209.
  • Most flight options: June has the highest number of flights from Portland to St. Louis, with approximately 38 flights per week, giving you more flexibility in scheduling your trip.
calendar iconMonthtemperature iconTemperaturecrowd level iconDemandflights iconWeekly Flightsprice iconAverage one-way Fare
January31.6°F (-0.2°C)Average18$214
February34.9°F (1.6°C)Moderately Low20$207
March46.4°F (8.0°C)Moderately High25$256
April56.1°F (13.4°C)Moderately High28$221
May66.6°F (19.2°C)Average33$194
June76.1°F (24.5°C)Moderately High38$241
July78.6°F (25.9°C)Average30$233
August77.0°F (25.0°C)Average35$211
September70.9°F (21.6°C)Average34$198
October58.6°F (14.8°C)Average32$209
November46.2°F (7.9°C)Moderately Low28$237
December37.8°F (3.2°C)Moderately Low27$237

*Average one-way fare is based on Expedia flight booking data from January 2025 to April 2026 for the specified route and travel class and may change depending on availability, dates, and demand.

Alternative routes from Portland (PDX) to St. Louis (STL)

  • Portland to St. Louis (PDX-SUS): Located approximately 16 miles from Lambert-St. Louis International Airport (STL), Spirit of St. Louis Airport (SUS) offers convenient access for travelers.
  • Astoria to St. Louis (AST-STL): Astoria Regional Airport (AST) is around 74 miles distant from Portland International Airport (PDX), providing an alternative route to St. Louis.
  • Portland to Springfield (PDX-SPI): About 85 miles from Lambert-St. Louis International Airport (STL), Abraham Lincoln Capital Airport (SPI) serves as another option for those traveling to the area.

How to find the best prices for flights from Portland (PDX) to St. Louis (STL)

Getting some of the best deals on flights from Portland to St. Louis is all about timing and flexibility. Here are some key tips to help you save:

  1. Best times to book and fly: cheaper fares are generally available when booking at least two months in advance, although most travelers tend to book 2 to 8 weeks ahead. Departures in the morning, between 5 a.m. and 12 p.m., often offer lower prices and are also the most popular flight times, while flying on Tuesday usually provides cheaper options, even though Thursday remains the most favored travel day.
  2. Set up price alerts: stay updated on price changes by using Expedia's Price Tracker. Receive alerts when fares drop for your selected route.
  3. Bundle and save: bundle your flight and hotel to save on Expedia, or unlock a hotel deal after booking your flight.*
  4. Compare flight options: use Expedia's search tool to compare airlines, routes, direct vs. non-direct flights, and flight times. You can also sort by price to find the most affordable options.
  5. Stay flexible with dates: being open to different travel days can sometimes help you find better prices on flights and hotels.
  6. Think about luggage: nowadays, it's important to check the airline's baggage policies to find the best value. That may be paying for an additional carry-on bag or booking a ticket with checked luggage included. Either way, double-check your allowance before confirming your booking to avoid excess baggage fees at the airport.

*Members only. Savings vary and are not available on all bundles. Select hotels.

Arriving at Lambert-St. Louis International Airport from Portland International Airport

St. Louis welcomes travelers from Portland with a range of transport options based on price, convenience, and proximity. Here's how to reach St. Louis efficiently:

  • Hotel transfer: Transfers offer a convenient way to reach your hotel in St. Louis, with private rides that can be arranged in advance.
  • Car rental: Renting a car from Lambert-St. Louis International Airport is a great option if you plan to explore and sightsee beyond the city. Browse cheap car rentals at Lambert-St. Louis International Airport on Expedia.
  • Taxi/ride-hailing: Taxis and ride-hailing services may be available from designated pickup areas outside the terminal, check locally on arrival.
  • Public transportation: From Lambert-St. Louis International Airport, Lambert Main Terminal Station, a metro station, is located just 0.1 miles away on foot, providing easy access to public transportation.

Frequently asked questions

How much does a flight from Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) cost?
You can find cheap one-way flights from $159 and cheap return flights from $240 Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) with Expedia. One-way flights typically cost between $169 and $767, and return flights often range between $269 and $1229. Flight prices vary based on the month and day of the week you want to travel, as well as the airline and how far in advance you book your ticket. Filter your search on Expedia by "Price (lowest to highest)" to see the cheapest fares first, and use the Price Tracking tool to receive alerts when Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) ticket fares go up or down.*Typical price ranges based on flights available on Expedia in the last year. Prices include multi-airline options.
What is the cheapest month to fly from Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
The cheapest month to fly from PDX to STL is September when demand is low. Traveling in off-peak or shoulder months is usually a good way to secure cheap tickets, just remember to avoid flying during holidays if you're able to. Use the calendar view in your search to see which months have low fares on this route.
Which airlines fly direct from Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
Enter PDX to STL and your travel dates, then apply the 'Nonstop' filter to see only direct flights.
What is the cheapest airline that flies from Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
American Airlines is one of the cheapest airlines offering connecting flights from Portland (PDX) to St. Louis (STL), with round-trip tickets starting from around $538. Use Expedia's search tool to compare the prices and schedules of airlines that fly this route to find the best option for your plans and budget.*Prices based on flights available on Expedia in the last year.
How do I find cheap flights from Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
To find a cheap flight from Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.), be flexible with your dates. Traveling outside of peak vacation months and booking a mid-week flight can help you save. Early morning and late night flights are often more affordable, too. Expedia allows you to compare flight times, airlines and routes all in one place to find low fares. You can also set up Price Tracking and receive alerts when fares go up or down.
What is the best airline to fly with from Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
The best airline to fly with from Portland, OR (PDX) to St. Louis, MO (STL) will differ from traveler to traveler. If you like to fly early, WN offers early morning flights. If price is the most important factor, Alaska Airlines typically offers the lowest fares. WN offers the most daily flights from PDX to STL, which is great if flexibility is what you value most. The best carrier for this journey could also be the one you have a loyalty membership with, as flying with that airline or another airline within the same alliance could help you collect points or enjoy lounge access.
What is the best time to fly from Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
The best time to fly is usually mid-week (Tuesday or Wednesday) and during early morning hours as flights tend to be cheaper, less crowded, and generally more on-time. Avoid major holidays and peak vacation seasons for smoother travel. Combining off-peak days and hours often gives the best combination of cost, comfort, and convenience.
How many flights per day from Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
You can find approximately 1 nonstop flights per day from Portland Intl. (PDX) to Lambert-St. Louis Intl. (STL). For more options, look at flights that include layovers.
What is the earliest flight from Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
The earliest flight from Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) typically leaves at around 12:05 AM local time, operated by American Airlines and Southern Airways Express. This seasonal service is available in June, allowing you to maximize your time in St. Louis. To compare early flights on Expedia, select the "Early Morning" and "Morning" filters in your search.
What are the most popular departure times for flights from Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
The most popular departure times for flights from Portland, OR (PDX) to St. Louis, MO (STL) are in the early morning, from 6am to 9am. About 27% of passengers prefer this time window. Many major carriers, including United Airlines and American Airlines, offer flights during this window. This timing works well because it allows you to arrive in St. Louis with a full day ahead of you.
How long does it take to fly from Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
Direct flights from PDX to STL usually take about 3 hours 50 minutes, traveling roughly 1,704 miles. If you opt for a connecting flight, expect to add around 3 hours 10 minutes to your journey. Keep in mind that actual flight times can vary due to wind patterns, weather, and air traffic.
Can you fly business or first class from Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
Select the "Business class" and "First class" filters when looking for PDX to STL flights on Expedia. This is the easiest way to compare prices, routes and flight times for your trip.
How do I earn miles on a Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) flight with Expedia?
It's easy to earn miles on a Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) flight when you book with Expedia. Before you confirm your booking, simply select your frequent flyer program and enter your program number. As a member of One Key™, you can also earn OneKeyCash™* on top of your airline miles when you book with Expedia.*Excludes taxes and fees. OneKeyCash is not redeemable for cash and can only be used on Expedia and other participating brands.
What airports do you fly into for St. Louis from Portland Intl. (PDX)?
From Portland Intl. (PDX), you can fly into Lambert-St. Louis Intl. (STL) to reach St. Louis. Some flights may connect through major hubs like Denver Intl. (DEN), Harry Reid Intl. (LAS), Sky Harbor Intl. (PHX) before reaching St. Louis. Compare routes and airports on Expedia to find the best flight options for your travel plans.
Is it cheaper to buy a plane ticket from Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) at the last minute?
Typically, booking a last minute flight from Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) will be more expensive than booking in advance. As the departure date approaches, there are usually fewer seats available which can drive up the cost. However, if there's some wiggle room with your travel dates and times, you could bag a cheap last-minute fare.
Is it cheaper to book a Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) flight and hotel package?
Securing a Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) St Louis Vacation Packages is usually cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your travels all in one place. Select from our extensive range of stays and then add flights, activities and car rentals to your booking. Bundle everything together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
If you booked your Portland, OR (PDX-Portland Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) flight within the last 24 hours, you may be able to modify or cancel it without any fees. Depending on the airline and the type of ticket you have, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in your itinerary or confirmation email. Or, head to our Customer Service portal if you'd like more information.

Travel information

Origin airport
Portland Intl.
Destination airport
Lambert-St. Louis Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Southwest Airlines, United
Roundtrip price
$240
Distance
1703 mi
Average flight time
7 hours 14 mins

Book with confidence

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 2026. You can also book with separate airlines for your outbound and return journeys, from $159 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.

 

Portland to St. Louis Flights

*Flight schedules are subject to change.

*Available to One Key members.

 

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