What is the cheapest airline that flies from Portland to Lambert-St Louis?

Hawaiian Airlines, American Airlines, and Delta are the most popular carriers operating from Portland to Lambert-St Louis

What airlines fly to St. Louis?

Delta, United Airlines and Southwest are the top three most popular airlines that fly to St. Louis from Portland according to our data. Delta is the first choice among our users, with 41% of people opting to fly with this airline when traveling to St. Louis. Keep in mind that there are 6 different airlines that fly to St. Louis on a routine basis, so you have a few additional options to choose from.

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?

As of July 2025, there are 6 operators available to choose from 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.

$81 Cheap Flights from Portland to St. Louis in 2025

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Find the cheapest flights from Portland to St. Louis

Round-trip

One-way

Last minute

Direct

Cheap round-trip flights

9:50 pm - 9:29 amPDX-STL

9h 39m1 stop

5:52 pm - 10:59 pmSTL-PDX

7h 07m1 stop

$173American Airlines

Find Deal

mar., ago. 5 - mar., ago. 12

5:00 am - 2:55 pmPDX-STL

7h 55m1 stop

6:30 pm - 12:05 amSTL-PDX

7h 35m1 stop

$174Southwest

Find Deal

jue., oct. 16 - lun., oct. 20

12:40 am - 10:33 amPDX-STL

7h 53m1 stop

2:25 pm - 6:00 pmSTL-PDX

5h 35m1 stop

$177Delta

Find Deal

lun., ago. 4 - mar., ago. 12

7:00 am - 5:40 pmPDX-STL

8h 40m2 stops

6:15 am - 11:45 amSTL-PDX

7h 30m1 stop

$178Southwest

Find Deal

mié., ago. 27 - mar., sep. 2

1:24 pm - 11:59 pmPDX-STL

8h 35m1 stop

3:35 pm - 10:47 pmSTL-PDX

9h 12m1 stop

$181Alaska Airlines

Find Deal

jue., sep. 11 - lun., sep. 15

6:27 am - 9:11 amPDX-STL

24h 44m1 stop

7:54 pm - 10:39 pmSTL-PDX

28h 45m1 stop

$190Frontier

Find Deal

vie., ago. 22 - mar., ago. 26

6:07 am - 8:32 pmPDX-STL

12h 25m1 stop

3:59 pm - 9:27 pmSTL-PDX

7h 28m1 stop

$193American Airlines

Find Deal

vie., sep. 26 - mar., sep. 30

5:05 pm - 12:38 amPDX-STL

5h 33m1 stop

7:15 pm - 11:35 pmSTL-PDX

6h 20m1 stop

$198Delta

Find Deal

lun., ago. 4 - mar., ago. 5

1:24 pm - 11:59 pmPDX-STL

8h 35m1 stop

6:00 am - 12:27 pmSTL-PDX

8h 27m1 stop

$222Alaska Airlines

Find Deal

vie., sep. 26 - dom., sep. 28

5:50 pm - 9:11 amPDX-STL

13h 21m1 stop

7:29 pm - 11:30 amSTL-PDX

18h 01m1 stop

$262Frontier

Find Deal

vie., ago. 1 - lun., ago. 4

American Airlines flights from Portland to St. Louis

Our best American Airlines deals on Portland to St. Louis flight tickets

American Airlines

Aug 5

PDX9:50 pmPortland

9h 39m

1 stop

STL9:29 amLambert-St Louis

Aug 12

STL5:52 pmLambert-St Louis

7h 07m

1 stop

PDX10:59 pmPortland

$173

Find similar

American Airlines

Sep 26

PDX6:07 amPortland

12h 25m

1 stop

STL8:32 pmLambert-St Louis

Sep 30

STL3:59 pmLambert-St Louis

7h 28m

1 stop

PDX9:27 pmPortland

$193

Find similar

American Airlines

Aug 22

PDX7:00 amPortland

11h 18m

1 stop

STL8:18 pmLambert-St Louis

Aug 24

STL6:14 pmLambert-St Louis

7h 45m

1 stop

PDX11:59 pmPortland

$218

Find similar

Alaska Airlines flights from Portland to St. Louis

Our best Alaska Airlines deals on Portland to St. Louis flight tickets

Alaska Airlines

Sep 11

PDX1:24 pmPortland

8h 35m

1 stop

STL11:59 pmLambert-St Louis

Sep 15

STL3:35 pmLambert-St Louis

9h 12m

1 stop

PDX10:47 pmPortland

$181

Find similar

Alaska Airlines

Sep 26

PDX1:24 pmPortland

8h 35m

1 stop

STL11:59 pmLambert-St Louis

Sep 28

STL6:00 amLambert-St Louis

8h 27m

1 stop

PDX12:27 pmPortland

$222

Find similar

Alaska Airlines

Jul 15

PDX10:40 amPortland

5h 55m

1 stop

STL6:35 pmLambert-St Louis

Jul 16

STL3:24 pmLambert-St Louis

7h 49m

1 stop

PDX9:13 pmPortland

$538

Find similar

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

Prices

Airlines

Other information

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 September is another great option to travel to St. Louis, with average flight prices from Portland averaging around $316.

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 Friday when prices can be found for as low as $366. 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 $596. 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 evening is the least expensive time of day to depart. momondo users have found prices as low as $288 when looking at flights departing in the evening. 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 $388 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 $260 on momondo.

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

There are 1 cabin classes 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.

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

As of July 2025, prices for Portland to St. Louis flights are approximately 12% cheaper 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

Best Price Found	$81
Fastest flight time	3h 45m
Direct flights	Mon and Sun
Airports in St. Louis	1 airport

The best one-way flight to St. Louis from Portland in the past 72 hours is $81. The best round-trip flight deal from Portland to St. Louis found on momondo in the last 72 hours is $173.

The fastest flight from Portland to St. Louis takes 3h 45m

Direct flights go from Portland to St. Louis on Monday and Sunday. The only airline offering direct flights is Southwest.

There is 1 airport near St. Louis: Lambert-St Louis (STL)

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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 45m.
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?
As of July 2025, there are 6 operators available to choose from 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?
momondo data reveals that the most frequently booked plane model on the route from Portland to St. Louis is Boeing 737 MAX 9, representing 22.22% of all bookings. The subsequent popular models are Boeing 737-800 Passenger/BBJ2 (winglets) at 15.56%, Boeing 737-900 Passenger/BBJ3 (winglets) at 15.56%, and Airbus A321-100/200 at 11.11%.
What is the most popular airline from Portland to St. Louis?
momondo data reveals that the most frequently booked airline on the route from Portland to St. Louis is Delta, representing 35% of all bookings. The subsequent popular airlines are United Airlines at 20%, Southwest at 18%, and American Airlines at 12%.

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
Frontier	PriceFrom $118	Free Cancellation	Rating 5.9 3,271 reviews	Search Frontier flights
American Airlines	PriceFrom $212	Free Cancellation	Rating 7.2 10,000 reviews	Search American Airlines flights
Delta	PriceFrom $212	Free Cancellation	Rating 8.0 7,951 reviews	Search Delta flights
United Airlines	PriceFrom $226	Free Cancellation	Rating 7.4 8,846 reviews	Search United Airlines flights
Alaska Airlines	PriceFrom $244	Free Cancellation	Rating 8.0 10,000 reviews	Search Alaska Airlines flights
Southwest	PriceFrom $252	Free Cancellation	Rating 8.0 4,249 reviews	Search Southwest flights

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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.