St. Louis

$128+ Cheap flights from Portland to St. Louis (PDX - STL)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 11/4. Fares are subject to change and may not be available on all flights or dates of travel.
PDX — STL
Jun 17 — Jun 241
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Portland to St. Louis with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

Cheapflights Tip: The best prices from Portland to Lambert-St Louis are usually found in January or September, booked 89 days in advance, depart on a Thursday or Monday and return on a Tuesday

Cheap flight deals from Portland to St. Louis

Discover tips and strategies to find the most affordable flight options for your journey from Portland (PDX) to St. Louis (STL). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated June 12, 2025.

Round-trip from

$244
(CheapOair)

One-way from

$128
(CheapOair)

Popular in

December

Cheapest in

January

Average price

$403

Good round-trip deal

$499 or less
From Portland to Lambert-St Louis
One-way flight from Portland to Lambert-St Louis
Highest demand for flights based on searches. 6% potential increase in price ($26 potential increase over avg. RT price).
Cheapest flight prices on average. 2% potential price decrease ($11 potential savings vs. average RT price).
Average for round-trip flights in June 2025
Price to beat on a round-trip flight from Portland to Lambert-St Louis.

Find flight deals from Portland to St. Louis

Cheapest flights from Portland to St. Louis
Explore the most affordable flight options available from Portland to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 12, 2025.

This CheapOair deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/16:05 amPDX - STL
1 stop25h 02mFrontier
Tue 10/77:52 pmSTL - PDX
1 stop28h 47mFrontier
Deal found 6/10$244
This American Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/133:22 pmPDX - STL
1 stop6h 54mAmerican Airlines
Wed 8/201:42 pmSTL - PDX
1 stop11h 38mAmerican Airlines
Deal found 6/9$282
This Delta deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/1011:11 pmPDX - STL
1 stop8h 22mDelta
Tue 7/157:15 pmSTL - PDX
1 stop6h 20mDelta
Deal found 6/11$297
This United Airlines deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/235:00 amPDX - STL
2 stops8h 44mUnited Airlines
Sun 8/315:15 amSTL - PDX
1 stop6h 13mUnited Airlines
Deal found 6/10$302
This Southwest deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/115:50 amPDX - STL
1 stop7h 10mSouthwest
Fri 7/182:50 pmSTL - PDX
1 stop7h 10mSouthwest
Deal found 6/10$307
This Mytrip deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 7/1310:23 amPDX - STL
2 stops21h 29mSpirit Airlines
Wed 7/1611:24 amSTL - PDX
2 stops23h 54mSpirit Airlines
Deal found 6/11$325
This Mytrip deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/212:12 pmPDX - STL
2 stops26h 52mMultiple Airlines
Sun 7/66:36 amSTL - PDX
1 stop28h 10mMultiple Airlines
Deal found 6/10$336
This Sun Country Air deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Sun Country Air is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/126:28 pmPDX - STL
1 stop23h 03mSun Country Air
Sun 7/206:05 amSTL - PDX
1 stop18h 41mSun Country Air
Deal found 6/10$345
This Alaska Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/271:25 pmPDX - STL
1 stop8h 34mAlaska Airlines
Sat 7/57:32 pmSTL - PDX
2 stops12h 47mAlaska Airlines
Deal found 6/9$456
This Hawaiian Airlines deal was found by Cheapflights users on 6/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Hawaiian Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 7/61:25 pmPDX - STL
1 stop8h 34mHawaiian Airlines
Tue 7/87:32 pmSTL - PDX
1 stop6h 27mHawaiian Airlines
Deal found 6/12$487

Cheapflights Fare Finder

Customize your flight search to find flights from Portland to St. Louis that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated June 12, 2025.
Use the filters below to find and compare flights from Portland to St. Louis that are best for you.

Fly from

Portland

Fly to

St. Louis

Route

Depart

Return

Price

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Wed 10/1

6:05 am-9:07 am

1 stop25h 02m

Lambert-St Louis

Tue 10/7

7:52 pm-10:39 pm

1 stop28h 47m

$244

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Wed 8/13

3:22 pm-12:16 am

1 stop6h 54m

Lambert-St Louis

Wed 8/20

1:42 pm-11:20 pm

1 stop11h 38m

$282

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Thu 7/10

12:40 am-8:34 am

1 stop5h 54m

Lambert-St Louis

Mon 7/21

5:37 pm-11:18 pm

1 stop7h 41m

$297

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Sat 8/23

5:00 am-3:44 pm

2 stops8h 44m

Lambert-St Louis

Sun 8/31

5:15 am-9:28 am

1 stop6h 13m

$302

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Fri 7/11

5:50 am-3:00 pm

1 stop7h 10m

Lambert-St Louis

Fri 7/18

2:50 pm-8:00 pm

1 stop7h 10m

$307

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Sun 7/13

10:23 am-9:52 am

2 stops21h 29m

Lambert-St Louis

Wed 7/16

11:24 am-9:18 am

2 stops23h 54m

$325

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Wed 7/2

12:12 pm-5:04 pm

2 stops26h 52m

Lambert-St Louis

Sun 7/6

6:36 am-8:46 am

1 stop28h 10m

$336

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Sat 7/12

6:28 pm-7:31 pm

1 stop23h 03m

Lambert-St Louis

Sun 7/20

6:05 am-10:46 pm

1 stop18h 41m

$345

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Fri 6/27

1:25 pm-11:59 pm

1 stop8h 34m

Lambert-St Louis

Sat 7/5

7:32 pm-6:19 am

2 stops12h 47m

$456

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Sun 7/6

1:25 pm-11:59 pm

1 stop8h 34m

Lambert-St Louis

Tue 7/8

7:32 pm-11:59 pm

1 stop6h 27m

$487

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/10

Showing 1-10 of 20 results
1
2

Best time to book a flight from Portland to St. Louis

Have a flexible travel schedule? Discover the best time to fly to St. Louis from Portland with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Portland to St. Louis

How far ahead should I book a flight from Portland to St. Louis?

Use this chart to determine the optimal time to book a round-trip flight from Portland to St. Louis. Price data was last updated on June 9, 2025.

The best time to book flights from Portland to St. Louis is 89 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

What is the cheapest month to book a flight from Portland to St. Louis?

Currently, August is the cheapest month in which you can book a flight from Portland to St. Louis (average of $311). Flying from Portland to St. Louis in March is currently the most expensive (average of $356). 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.

What is the cheapest time of day to fly from PDX to STL?

Find hourly flight availability from Portland to St. Louis. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated June 12, 2025.

Unlike at noon, when flights are generally more expensive, you can save up to 58% on flights from Portland to St. Louis by exploring options for tickets in the evening.

What is the cheapest day to fly from Portland to St. Louis?

Use this chart to determine the cheapest time to fly round-trip from Portland to St. Louis. Price data was last updated on June 8, 2025.

Travelers seeking maximum savings on their Portland to St. Louis flight should consider departing on Thursday evenings when fares are most often at their lowest. Sunday at noon flights should be avoided if possible as fares are typically the most expensive at this time.

Rainfall in St. Louis by month

Plan your trip to St. Louis by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in St. Louis ranges from 2.2 - 4.7 inches per month. May is typically the wettest month, when rainfall can reach 4.7 in. February is typically the driest time to visit St. Louis when rainfall is around 2.2 in.

Temperature in St. Louis by month

Plan your trip to St. Louis by taking into account the average temperature totals by month.

If weather is an important factor for your trip to St. Louis, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 80.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 32.0 F).

Reviews of airlines servicing St. Louis

Get insights into the airlines that provide service to St. Louis. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to St. Louis. Reviews last updated June 12, 2025.
Read through reviews of airlines operating flights from Portland to St. Louis, such as Alaska Airlines, Southwest and Delta. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.

Boarding

8.1

Comfort

7.8

Entertainment

7.1

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Boarding

8.1

Comfort

7.8

Entertainment

7.1

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Boarding

8.1

Comfort

7.8

Entertainment

7.1

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
8.0
Very good

Boarding

8.1

Comfort

7.8

Entertainment

7.1

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Boarding

8.1

Comfort

7.8

Entertainment

7.1

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Boarding

8.1

Comfort

7.8

Entertainment

7.1

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Related info for your journey

Find useful and relevant information for your journey from Portland to St. Louis. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
  • What are the cheapest airlines flying from Portland to St. Louis round-trip?

    Currently priced at $244, Frontier will fly you from Portland to St. Louis and back. In addition to Frontier, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from American Airlines and Delta - these airlines can fly you to your destination from $282 and $297, respectively. Users have found that Frontier is 36% cheaper than the other options available to this destination.

  • What are the cheapest airlines to fly from Portland to St. Louis one-way?

    To fly one-way, consider booking your trip with Frontier, which is currently one of the cheapest options available, starting at $128. American Airlines flights start at $139 while deals on Spirit Airlines start at $140 one-way.

  • What are the cheapest flights from Portland to St. Louis?

    Looking at all options, your cheapest flight can be booked for $376. While the most popular route (Portland - Lambert-St Louis) can be booked for $276 on average our data indicates $555 when flying from Portland to St. Louis.

  • Where are the most common layover locations when flying from Portland to St. Louis?

  • What are some popular things to do or see while on a layover in Salt Lake City?

    If you're on a layover in Salt Lake City and looking for things to do, consider visiting Temple Square, Salt Lake Temple, or Hogle Zoo. Temple Square, Salt Lake Temple, and Hogle Zoo are located about 4.7 mi, 4.8 mi, and 9.1 mi, respectively from Salt Lake City. Travelers can rent a car at Salt Lake City for an average daily rate of $55 to make sightseeing during their layover a little easier.

  • Where are the least popular layover locations for Portland to St. Louis flights?

  • Can I find deals for flights from Portland to St. Louis that include hotel bookings?

    Yes. In addition to deals on Portland to St. Louis flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Portland to St. Louis?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Portland to St. Louis.

  • Can I find deals for business class flights from Portland to St. Louis?

    Yes. Cheapflights offers flight deals from Portland to St. Louis by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Portland to St. Louis?

    Currently, August is the cheapest month in which you can book a flight from Portland to St. Louis (average of $311). Flying from Portland to St. Louis in March is currently the most expensive (average of $356). 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.

See more FAQs

Traveling to a place near Portland?

Book flights to Portland if you plan to visit one of these locations
O'Fallon
Maryland Heights
Fairview Heights
Collinsville
Eureka
St. Peters
Glencoe
Festus
Alton
Farmington

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Top 6 airlines flying from Portland to St. Louis

Discover the top 6 airlines that operate flights from Portland to St. Louis. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated June 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$118Average$221FlexibilityNo cancel feeOn-time62%
American AirlinesCheapest$196Average$384FlexibilityNo cancel feeOn-time71%
DeltaCheapest$212Average$367FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$226Average$428FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$244Average$440FlexibilityNo cancel feeOn-time75%
SouthwestCheapest$252Average$459FlexibilityNo cancel feeOn-time63%

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.