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

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Flight deals from Portland to St Louis

Looking for a cheap last-minute deal or the best round-trip flight from Portland to St Louis? Find the lowest prices on one-way and round-trip tickets right here.

Find the cheapest month to fly from Portland to St Louis

We’re always keeping an eye on fares, so you can find the best one in seconds. It looks like Portland to St Louis flights are currently cheapest in November.

Direct flights from Portland to St Louis

Portland to St Louis: Alternative routes

Compare routes from Portland to St Louis below. You may find an airport to fly into that's cheaper, faster, or easier than St Louis.

Portland to St Louis: Flight information

The things to know before you go.
Cheapest flight found$131
Cheapest month to flyNovember
Average flight time3 hrs, 43 mins
Most popular airlineSouthwest Airlines
Average flights per week2

Finding cheap flights from Portland to St Louis: Frequently asked questions

The best price we found for a round-trip flight from Portland to St Louis is $277. This is an estimate based on information collected from different airlines and travel providers over the last 4 days and is subject to change and availability.
3 hours and 43 minutes is the average flight time from Portland to St Louis.
Southwest Airlines flies direct from Portland to St Louis.
There are 2 flights per week flying from Portland to St Louis, as of June 2025.
The cheapest month to fly from Portland to St Louis is usually June 2025.
After crunching the numbers on our flight calendar, we found that it's currently cheapest to fly from Portland Airport to St Louis Airport on Monday, September 15, 2025.
Yes – the average flight time is 3 hours and 43 minutes.
We show every price from over 1,200 airlines and travel agents, comparing them all so you don’t have to. If you know you want to fly to St Louis but you’re not ready to book, set up a Price Alert. We’ll track prices for you, and let you know when they rise or fall.
We crunched all the numbers in our flight calendar, and it looks like the cheapest time to book a flight to St Louis is around 40 days in advance, so don’t leave your flight to the last minute.
Currently, Alaska Airlines and Southwest Airlines offer the cheapest flight tickets to St Louis.

Traveling from Portland International Airport (PDX) to Lambert-St. Louis International Airport (STL): what you need to know

  • The average duration of a direct flight from Portland International Airport to Lambert-St. Louis International Airport is 3 hours 45 minutes.

  • St Louis's timezone is UTC-5, which makes St Louis two hours ahead of Portland.

  • Arriving two hours before an international flight and one hour ahead of a domestic departure are golden rules for stress-free travel. Make sure you're at the airport on time to board your PDX to STL flight.

  • During popular months like July, it's a good idea to get to the airport earlier than normal. Arrive two hours before domestic departures and four hours ahead of international flights whenever you're flying during a peak period in general.

  • Getting to St Louis (and then seeing more of United States!) is a breeze with Southwest Airlines. This popular carrier offers direct flights from Portland International Airport to Lambert-St. Louis International Airport.

  • The airline most travelers fly with on this route is Southwest Airlines.

  • Consider adding a stopover when booking your ticket from Portland International Airport to Lambert-St. Louis International Airport. Just uncheck 'Direct flights only' to break up your trip, or enjoy a detour to a new and interesting place. Check out these options between PDX and STL:

    • Denver International Airport

    • Salt Lake City International Airport

    • Minneapolis-St. Paul International Airport

How to find the cheapest flights from Portland International Airport (PDX) to Lambert-St. Louis International Airport (STL)

  • $131 is currently the lowest price for a one-way Portland International Airport to Lambert-St. Louis International Airport flight. Return flights start from $277. These fares can change depending on availability.

  • Book six months before you want to fly. After looking at the numbers on our calendar, this is how far you'll want to book ahead to find cheap tickets from PDX to STL.

  • Plan your trip for May. That's the cheapest month for flights from Portland International Airport to Lambert-St. Louis International Airport. If you're flexible on when you fly, use the 'Whole month' tool to find the lowest price across every month.

  • Snapping up cheap flights from PDX to STL couldn't be easier with Price Alerts. Simply create one of these automatic alerts and we'll get in touch when fares go down.

  • Pick your ideal departure and arrival times, number of stops and airlines with the filters. Alternatively, sort your results by 'Cheapest' to see the best deals on flights from Portland International Airport to Lambert-St. Louis International Airport.

Handy information about Portland International Airport (PDX)

  • You'll find PDX at 7000 NE Airport Way.

  • Portland International Airport earns top marks for on-time performance. 83.65% of flights that take off from PDX arrive at their destination on time.

  • To reach Portland International Airport from central Portland, it'll take around 20 minutes if you're traveling by car. This depends on traffic, however. It's approximately 12 miles from the airport to the city center.

  • Planning to take public transport? Expect a trip time of around 45 minutes.

  • Get your vacation off to a leisurely start by staying near PDX. Whether you're boarding an early flight from Portland International Airport to Lambert-St. Louis International Airport or just don't want to be rushed, these hotels have you covered:

Arriving at Lambert-St. Louis International Airport (STL)

Getting from Lambert-St. Louis International Airport (STL) to central St Louis

  • STL is located at 10701 Lambert International Blvd..

  • From Lambert-St. Louis International Airport, St Louis is approximately 16 miles away. It takes around 20 minutes to get to the center driving.

  • It takes roughly 35 minutes if you're using public transport.

When to fly to Lambert-St. Louis International Airport (STL)

  • It's time to plan your dates for your flight from Portland International Airport to Lambert-St. Louis International Airport. July is the most popular month to head to St Louis. If you'd like a quieter vibe, go in April.

  • The warmest month in St Louis is July, with the temperature ranging between 63ºF and 91ºF. Lock in your flights from Portland International Airport to Lambert-St. Louis International Airport in this month if this is the kind of weather you like.

  • For cooler conditions, look for a cheap ticket from PDX to STL in January. Temperatures average between 18ºF and 45ºF then.

Explore more of United States

  • You've visited St Louis, now it's time to discover other parts of United States. Travel around 260 miles north-east to Chicago to tick off its popular sights. From Millennium Park to Art Institute of Chicago and LandShark Beer Garden at Navy Pier, you've got a jam-packed schedule ahead.

  • If you want to check out another corner of United States, head for Indianapolis, about 230 miles east of St Louis. The Children's Museum of Indianapolis, Indianapolis Museum of Art and Indianapolis Zoo are among its highlights.

Prices shown on this page are estimated lowest prices only. Found in the last 45 days.