Cheap Flights From Washington Dulles Intl. (IAD) To Lambert-St. Louis Intl. (STL)

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Cheapest Flights from Washington (IAD) to St. Louis (STL)

The cheapest flights to Lambert-St. Louis Intl. found within the past 7 days were CA $1,312 round trip and CA $667 one way. Prices and availability subject to change. Additional terms may apply.

Fri, Sep 25 - Sun, Sep 27
IAD
Washington
STL
St. Louis
CA $1,312 Roundtrip, found 10 hours ago
CA $1,312
Roundtrip
found 10 hours ago
Select Alaska Airlines flight, departing Fri, Sep 25 from Washington to St. Louis, returning Sun, Sep 27, priced at CA $1,312 found 10 hours ago
Fri, Sep 25 - Sun, Sep 27
IAD
Washington
STL
St. Louis
CA $1,383 Roundtrip, found 10 hours ago
CA $1,383
Roundtrip
found 10 hours ago
Select Alaska Airlines flight, departing Fri, Sep 25 from Washington to St. Louis, returning Sun, Sep 27, priced at CA $1,383 found 10 hours ago
Fri, Sep 25 - Sun, Sep 27
IAD
Washington
STL
St. Louis
CA $1,391 Roundtrip, found 10 hours ago
CA $1,391
Roundtrip
found 10 hours ago
Select Alaska Airlines flight, departing Fri, Sep 25 from Washington to St. Louis, returning Sun, Sep 27, priced at CA $1,391 found 10 hours ago
Fri, Sep 25 - Sun, Sep 27
IAD
Washington
STL
St. Louis
CA $1,462 Roundtrip, found 10 hours ago
CA $1,462
Roundtrip
found 10 hours ago
Select Alaska Airlines flight, departing Fri, Sep 25 from Washington to St. Louis, returning Sun, Sep 27, priced at CA $1,462 found 10 hours ago
Fri, Sep 25 - Sun, Sep 27
IAD
Washington
STL
St. Louis
CA $1,470 Roundtrip, found 10 hours ago
CA $1,470
Roundtrip
found 10 hours ago
Select Alaska Airlines flight, departing Fri, Sep 25 from Washington to St. Louis, returning Sun, Sep 27, priced at CA $1,470 found 10 hours ago

Frequently asked questions

Are there direct flights from IAD to Lambert-St. Louis Intl. Airport (STL)?
For a no-fuss trip between Sterling and St. Louis, take a look at United Airlines. They offer direct flights from Dulles Intl. Airport to STL.
What airlines fly from IAD to STL?
Ready to book the ticket for your next incredible adventure? Eager to travel from IAD to Lambert Field as fast as possible? Step aboard one of the 91 nonstop flights offered by United Airlines each month, and you'll be landing before you can ask 'Are we there yet?'
What is the best day to buy a plane ticket?
Airfares offered on Friday tend to be the cheapest, according to flight demand on Travelocity.ca in 2021. Purchasing your airfares on a Thursday or Saturday can also provide better value, however our advice if you're looking to save money is to avoid booking on a Wednesday or Sunday. Our data shows that those two days have the highest ticket values on average, so keep this in mind if you're browsing flight deals.
What are the cheapest days to fly?
Frequent travellers may already know this, but earlier in the week is often the cheapest time to fly. Flights departing on a Monday are the cheapest of the week. Since flights towards the middle of the week tend to be more popular, this causes the prices to rise. This is why, on average, airfares booked on Travelocity.ca in 2021 were most expensive for Wednesday departures.
How far in advance can you book a flight?
Here's the deal: It is typically possible to start comparing international airfares on Travelocity.ca up to 12 months in advance. However, it does depend on the carrier as not all airlines release their prices that far out. According to our 2021 flight demand trends, last minute planners can still bag a bargain with some of the cheapest fares appearing 2-4 weeks prior to their travel dates.*According to flight demand on Travelocity.ca from January to December 2021. Savings are subject to change and may vary depending on selections made.
*Price based on the lowest price found within past 24 hours and based upon one night stay for two adults over the next thirty days. Prices and availability subject to change. Additional terms may apply.