Cheap flights from Portland to St. Louis from $81

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Portland to St. Louis departing on 1/29. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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0 bags

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Cheap round-trip flights

Enter your travel dates to find the best prices.
Frontier Logo
11:28 am - 9:06 pm
PDX
-
STL
7h 38m1 stop
Frontier Logo
10:01 pm - 9:49 am
STL
-
PDX
13h 48m1 stop
$181Frontier
Thu, Jan 29 - Thu, Feb 5
Frontier Logo
11:28 am - 6:44 pm
PDX
-
STL
29h 16m2 stops
Frontier Logo
10:01 pm - 9:49 am
STL
-
PDX
13h 48m1 stop
$204Frontier
Thu, Jan 29 - Thu, Feb 5
Delta Logo
5:00 pm - 12:25 am
PDX
-
STL
5h 25m1 stop
Delta Logo
3:05 pm - 9:12 pm
STL
-
PDX
8h 07m1 stop
$225Delta
Wed, Mar 4 - Mon, Mar 9
United Airlines Logo
8:30 am - 9:05 pm
PDX
-
STL
10h 35m2 stops
United Airlines Logo
4:30 pm - 9:15 pm
STL
-
PDX
6h 45m1 stop
$230United Airlines
Wed, Feb 18 - Sat, Feb 21
United Airlines Logo
1:24 pm - 8:58 pm
PDX
-
STL
5h 34m1 stop
United Airlines Logo
4:49 pm - 10:32 pm
STL
-
PDX
7h 43m1 stop
$236United Airlines
Fri, Jan 30 - Mon, Feb 2
Delta Logo
5:08 pm - 12:25 am
PDX
-
STL
5h 17m1 stop
Delta Logo
3:40 pm - 8:30 pm
STL
-
PDX
6h 50m1 stop
$237Delta
Fri, Feb 13 - Sat, Feb 21
United Airlines Logo
8:30 am - 9:05 pm
PDX
-
STL
10h 35m2 stops
United Airlines Logo
6:00 pm - 11:14 pm
STL
-
PDX
7h 14m1 stop
$241United Airlines
Wed, Feb 18 - Sun, Feb 22
United Airlines Logo
1:24 pm - 8:58 pm
PDX
-
STL
5h 34m1 stop
United Airlines Logo
6:00 am - 12:18 pm
STL
-
PDX
8h 18m1 stop
$245United Airlines
Sat, Jan 17 - Sun, Jan 18
United Airlines Logo
11:05 pm - 10:41 am
PDX
-
STL
9h 36m1 stop
United Airlines Logo
8:45 am - 1:45 pm
STL
-
PDX
7h 00m1 stop
$248United Airlines
Tue, Jan 20 - Sun, Jan 25
American Airlines Logo
10:15 pm - 9:40 am
PDX
-
STL
9h 25m1 stop
American Airlines Logo
6:00 am - 11:45 am
STL
-
PDX
7h 45m1 stop
$249American Airlines
Thu, Jan 29 - Mon, Feb 2

American Airlines flights from Portland to St. Louis

Our best American Airlines deals on Portland to St. Louis flight tickets
American Airlines
Jan 29
PDX10:15 pmPortland
9h 25m
1 stop
STL9:40 amLambert-St Louis
Feb 2
STL6:00 amLambert-St Louis
7h 45m
1 stop
PDX11:45 amPortland
American Airlines
Apr 16
PDX11:40 pmPortland
7h 17m
1 stop
STL8:57 amLambert-St Louis
Apr 18
STL5:20 amLambert-St Louis
7h 41m
1 stop
PDX11:01 amPortland
American Airlines
Feb 3
PDX6:00 amPortland
6h 50m
1 stop
STL2:50 pmLambert-St Louis
Feb 12
STL1:34 pmLambert-St Louis
9h 10m
1 stop
PDX8:44 pmPortland

Delta flights from Portland to St. Louis

Our best Delta deals on Portland to St. Louis flight tickets
Delta
Mar 4
PDX5:00 pmPortland
5h 25m
1 stop
STL12:25 amLambert-St Louis
Mar 9
STL3:05 pmLambert-St Louis
8h 07m
1 stop
PDX9:12 pmPortland
Delta
Feb 13
PDX5:08 pmPortland
5h 17m
1 stop
STL12:25 amLambert-St Louis
Feb 21
STL3:40 pmLambert-St Louis
6h 50m
1 stop
PDX8:30 pmPortland
Delta
Jan 27
PDX7:37 pmPortland
12h 02m
2 stops
STL9:39 amLambert-St Louis
Feb 3
STL6:35 amLambert-St Louis
14h 15m
2 stops
PDX6:50 pmPortland

momondo 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, momondo users made 832,500 searches. Data last updated January 2, 2026.
Use the filters below to find and compare flights from Portland to St. Louis that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Thu 1/29

11:28 am-9:06 pm

1 stop7h 38m

Lambert-St Louis

Thu 2/5

10:01 pm-9:49 am

1 stop13h 48m

$181

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Thu 1/29

11:28 am-6:44 pm

2 stops29h 16m

Lambert-St Louis

Thu 2/5

10:01 pm-9:49 am

1 stop13h 48m

$204

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Wed 3/4

5:00 pm-12:25 am

1 stop5h 25m

Lambert-St Louis

Mon 3/9

3:05 pm-9:12 pm

1 stop8h 07m

$225

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Wed 2/18

8:30 am-9:05 pm

2 stops10h 35m

Lambert-St Louis

Sat 2/21

4:30 pm-9:15 pm

1 stop6h 45m

$230

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Fri 1/30

1:24 pm-8:58 pm

1 stop5h 34m

Lambert-St Louis

Mon 2/2

4:49 pm-10:32 pm

1 stop7h 43m

$236

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Fri 2/13

5:08 pm-12:25 am

1 stop5h 17m

Lambert-St Louis

Sat 2/21

3:40 pm-8:30 pm

1 stop6h 50m

$237

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Wed 2/18

8:30 am-9:05 pm

2 stops10h 35m

Lambert-St Louis

Sun 2/22

6:00 pm-11:14 pm

1 stop7h 14m

$241

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Sat 1/17

1:24 pm-8:58 pm

1 stop5h 34m

Lambert-St Louis

Sun 1/18

6:00 am-12:18 pm

1 stop8h 18m

$245

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Tue 1/20

11:05 pm-10:41 am

1 stop9h 36m

Lambert-St Louis

Sun 1/25

8:45 am-1:45 pm

1 stop7h 00m

$248

PortlandSt. Louis

PDX - STL

PDXSTL

Portland

Thu 1/29

10:15 pm-9:40 am

1 stop9h 25m

Lambert-St Louis

Mon 2/2

6:00 am-11:45 am

1 stop7h 45m

$249

Flights are sorted by cheapest round-trip flights first.

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See travel insights to St. Louis from

How to get the cheapest flight ticket from Portland to St. Louis

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the cheapest month to fly to St. Louis?

In general, January is the cheapest month to fly from Portland to St. Louis. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $280. The month of November is another great option to travel to St. Louis, with average flight prices from Portland averaging around $300.

What is the cheapest day to depart on your flight to St. Louis?

The cheapest day to depart on your flight to St. Louis is on a Saturday when prices can be found for as low as $548. This is often the case because there is less demand to fly during this day of the week. If your travel schedule is flexible, try to avoid departing on a Sunday because tickets tend to average around $621. These prices are subject to change though, so be sure to set up a Price Alert for flights to St. Louis.

What is the cheapest time of day to depart on your flight to St. Louis?

Flying to St. Louis from Portland in the morning is the least expensive time of day to depart. momondo users have found prices as low as $526 when looking at flights departing in the morning. At noon is when there is more demand to fly to St. Louis, so prices are often more expensive at around $679 per ticket.

What is the cheapest Portland to Lambert-St Louis flight route?

Fly from Portland to Lambert-St Louis for the best Portland - Lambert-St Louis flight prices

How far in advance should I book a flight to St. Louis?

You are more likely to see cheaper flights to St. Louis from Portland when booking weeks ahead of your departure date. In general, you can expect to find flights to St. Louis for around $371 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to St. Louis from Portland for as low as $245 on momondo.

What cabin class options are available on Portland to Lambert-St Louis flights?

There is only 1 cabin class available to choose from on Portland to Lambert-St Louis flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on Portland to St. Louis flights?

No. A direct flight is the cheapest option for a flight between Portland to St. Louis.

How have Portland to St. Louis flight prices changed over time?

As of January 2026, prices for Portland to St. Louis flights are approximately 68% more expensive when compared to flights at the same time last year.

When to book flights from Portland to St. Louis

Are you open to changing your travel dates? Check out the ideal times to fly from Portland to St. Louis according to our flight data. Find out which month and days have the cheapest flights.
Estimated round-trip price

Cheap Portland to St. Louis (PDX to STL) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Portland to St. Louis

Fastest flight time

3h 48m

Direct flights

Mon, Tue, Wed, Thu, Fri and Sat

Airports in St. Louis

1 airport
The fastest flight from Portland to St. Louis takes 3h 48m
Direct flights go from Portland to St. Louis on Monday, Tuesday, Wednesday, Thursday, Friday and Saturday. There are no airlines offering direct flights.
There is 1 airport in St. Louis. From Portland there are direct flights to Lambert-St Louis (STL).
  • How far is Portland to Lambert-St Louis by plane?

    A flight from Portland to Lambert-St Louis will travel around 1718.1 mi. A reasonable flight in good conditions will take 3h 48m.

  • When did momondo last update prices for flights from Portland Airport to Lambert-St Louis Airport?

    Prices for flights from Portland Airport to Lambert-St Louis Airport are updated daily.

  • How many operators does momondo search for flights from Portland Airport to Lambert-St Louis Airport?

  • How old do you have to be to fly from Portland Airport to Lambert-St Louis Airport?

    The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Portland Airport to Lambert-St Louis Airport.

  • What documentation or ID do you need to fly to Lambert-St Louis Airport?

    The travel and health documents required for your trip to Lambert-St Louis Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Lambert-St Louis Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

  • What is the most popular plane model from Portland to St. Louis?

  • What is the most popular airline from Portland to St. Louis?

Best airlines flying from Portland to St. Louis

Compare and see reviews for airlines that fly from Portland to St. Louis with momondo
Airline
Rating
Free Cancellation
Price
FrontierPriceFrom $158Free CancellationRating
5.7
3,066 reviews
Search Frontier flights
DeltaPriceFrom $221Free CancellationRating
7.9
8,022 reviews
Search Delta flights
American AirlinesPriceFrom $226Free CancellationRating
7.2
11,075 reviews
Search American Airlines flights
United AirlinesPriceFrom $226Free CancellationRating
7.4
9,133 reviews
Search United Airlines flights
SouthwestPriceFrom $246Free CancellationRating
8.0
4,255 reviews
Search Southwest flights
Alaska AirlinesPriceFrom $249Free CancellationRating
8.0
11,600 reviews
Search Alaska Airlines flights

Traveling to a place near St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
St. Charles
Chesterfield
Hermann
Fairview Heights
Maryland Heights
O'Fallon
Florissant
Fenton
Collinsville
St. Peters
Wentzville
Alton
Farmington
Clayton
Glencoe
Eureka
Festus
Edwardsville
Litchfield
Shrewsbury

Why use momondo?

Why should I use momondo to find a flight deal from Portland to St. Louis?

It is quick and easy to find Portland to St. Louis flights on momondo. We search and return numerous flight options from various airlines and agents. You can then use our filters to narrow your search until you have found the most convenient flight to St. Louis that suits you.

Can I find flights from Portland to St. Louis with flexible booking policies on momondo?

momondo does allow users to show only those flights to St. Louis from Portland which offer a flexible booking policy as well as other useful filters and features.

How can momondo help me find flights from Portland to St. Louis?

Once you have performed a search for Portland to St. Louis flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.

I’m not ready to book a flight from Portland to St. Louis right now. Can momondo alert me if prices change?

Of course. momondo tracks the price of Portland to St. Louis flights. All you need is a valid email address and we will do the rest; it is that quick and easy.

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1 adult
Sun 2/1
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