Cheap flights from Portland, Maine to St. Louis from $154
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, Maine to St. Louis departing on 7/13. 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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How to get the cheapest flight ticket from Portland, Maine 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, February is the cheapest month to fly from Portland, Maine to St. Louis. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $250. The month of January is another great option to travel to St. Louis, with average flight prices from Portland, Maine averaging around $371.
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 Tuesday when prices can be found for as low as $443. 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 Monday because tickets tend to average around $638. 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, Maine in the afternoon is the least expensive time of day to depart. momondo users have found prices as low as $441 when looking at flights departing in the afternoon. At noon is when there is more demand to fly to St. Louis, so prices are often more expensive at around $609 per ticket.
How have Portland, Maine to St. Louis flight prices changed over time?
As of June 2025, prices for Portland, Maine to St. Louis flights are approximately 17% cheaper when compared to flights at the same time last year.
What is the cheapest airline that flies from Portland to Lambert-St Louis?
Sun Country Air, Delta, and American Airlines are the most popular carriers operating from Portland to Lambert-St Louis
What airlines fly to St. Louis?
American Airlines, Southwest and Delta are the top three most popular airlines that fly to St. Louis from Portland, Maine according to our data. American Airlines is the first choice among our users, with 60% 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 to book flights from Portland, Maine to St. Louis
Cheap Portland, Maine to St. Louis (PWM to STL) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from Portland, Maine to St. Louis
How far is Portland to Lambert-St Louis by plane?
The distance between Portland and Lambert-St Louis is about 1090.4 mi. 4h 36m is a normal flight duration for this route.
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 refresh daily.
How many operators does momondo search for flights from Portland Airport to Lambert-St Louis Airport?
The number of operators available for flights from Portland Airport to Lambert-St Louis Airport is 4 as of June 2025.
How old do you have to be to fly from Portland Airport to Lambert-St Louis Airport?
Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify 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 you'll need for your trip to Lambert-St Louis Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Lambert-St Louis Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.
What is the most popular airline from Portland, Maine to St. Louis?
Based on momondo bookings for this flight route, the most popular airline on flight routes from Portland, Maine to St. Louis is American Airlines (59% of total bookings). The next most popular airlines are Delta (21%), United Airlines (12%), and Southwest (9%).
Best airlines flying from Portland, Maine to St. Louis
Compare and see reviews for airlines that fly from Portland, Maine to St. Louis with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $311 | Free Cancellation | Rating 8.0 7,963 reviews | |||
| PriceFrom $316 | Free Cancellation | Rating 7.2 10,000 reviews | |||
| PriceFrom $341 | Free Cancellation | Rating 7.4 8,801 reviews | |||
| PriceFrom $351 | Free Cancellation | Rating 8.0 4,278 reviews |
Traveling to a place near St. Louis?
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Why should I use momondo to find a flight deal from Portland to St. Louis?
Finding the right flight to St. Louis from Portland is quick and easy when you have a range of options in front of you, from reputable agents and recognisable airlines. Options that can then be filtered down to find the best fit. That is what momondo does. We make finding flights to St. Louis quick and easy, saving you time and money.
Can I find flights from Portland to St. Louis with flexible booking policies on momondo?
Flights from Portland to St. Louis with flexible booking policies can be found by using the search form above and then selecting our dedicated flexible booking filter, which will highlight only the flights where this policy is applied.
How can momondo help me find flights from Portland to St. Louis?
momondo helps you find the best flight between Portland and St. Louis by providing filters to narrow your choice of flights to those matching your criteria. You can select flights based on numerous factors such as price, departure and landing times, airport and airline.
I’m not ready to book a flight from Portland to St. Louis right now. Can momondo alert me if prices change?
If you are simply researching potential flights to St. Louis, momondo offers a useful price alert feature which will track prices for flights to St. Louis from Portland and alert you when they change.