$666 Cheap Flights from Reykjavik (KEF) to St. Louis (STL)

View $666 flight on Fri, Apr 25, 2025Opens in a new window

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Find available prices by choosing your travel dates.

Cheap Flights from Reykjavik to St. Louis (KEF-STL)

Prices were available within the past 7 days and start at $666 for one-way flights and $751 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Sat, May 31 - Sun, Jun 1
KEF
Reykjavik
STL
St. Louis
$751 Roundtrip, found 6 days ago
$751
Roundtrip
found 6 days ago
Select Delta flight, departing Sat, May 31 from Reykjavik to St. Louis, returning Sun, Jun 1, priced at $751 found 6 days ago
United
Thu, Jun 26 - Fri, Jul 11
KEF
Reykjavik
STL
St. Louis
$758 Roundtrip, found 6 days ago
$758
Roundtrip
found 6 days ago
Select United flight, departing Thu, Jun 26 from Reykjavik to St. Louis, returning Fri, Jul 11, priced at $758 found 6 days ago
United
Sun, Jun 1 - Sat, Jun 7
KEF
Reykjavik
STL
St. Louis
$762 Roundtrip, found 6 days ago
$762
Roundtrip
found 6 days ago
Select United flight, departing Sun, Jun 1 from Reykjavik to St. Louis, returning Sat, Jun 7, priced at $762 found 6 days ago
Air Canada
Fri, Jun 27 - Fri, Jul 11
KEF
Reykjavik
STL
St. Louis
$764 Roundtrip, found 6 days ago
$764
Roundtrip
found 6 days ago
Select Air Canada flight, departing Fri, Jun 27 from Reykjavik to St. Louis, returning Fri, Jul 11, priced at $764 found 6 days ago
United
Wed, Jul 2 - Fri, Jul 11
KEF
Reykjavik
STL
St. Louis
$768 Roundtrip, found 6 days ago
$768
Roundtrip
found 6 days ago
Select United flight, departing Wed, Jul 2 from Reykjavik to St. Louis, returning Fri, Jul 11, priced at $768 found 6 days ago
United
Mon, Jun 2 - Sun, Jun 8
KEF
Reykjavik
STL
St. Louis
$769 Roundtrip, found 6 days ago
$769
Roundtrip
found 6 days ago
Select United flight, departing Mon, Jun 2 from Reykjavik to St. Louis, returning Sun, Jun 8, priced at $769 found 6 days ago
United
Wed, May 28 - Sat, Jun 7
KEF
Reykjavik
STL
St. Louis
$772 Roundtrip, found 6 days ago
$772
Roundtrip
found 6 days ago
Select United flight, departing Wed, May 28 from Reykjavik to St. Louis, returning Sat, Jun 7, priced at $772 found 6 days ago
United
Thu, Jul 31 - Fri, Aug 8
KEF
Reykjavik
STL
St. Louis
$773 Roundtrip, found 1 day ago
$773
Roundtrip
found 1 day ago
Select United flight, departing Thu, Jul 31 from Reykjavik to St. Louis, returning Fri, Aug 8, priced at $773 found 1 day ago
Virgin Atlantic
Sat, May 31 - Sun, Jun 1
KEF
Reykjavik
STL
St. Louis
$795 Roundtrip, found 6 days ago
$795
Roundtrip
found 6 days ago
Select Virgin Atlantic flight, departing Sat, May 31 from Reykjavik to St. Louis, returning Sun, Jun 1, priced at $795 found 6 days ago
KLM
Sat, May 31 - Sun, Jun 1
KEF
Reykjavik
STL
St. Louis
$838 Roundtrip, found 6 days ago
$838
Roundtrip
found 6 days ago
Select KLM flight, departing Sat, May 31 from Reykjavik to St. Louis, returning Sun, Jun 1, priced at $838 found 6 days ago
Flights from Reykjavik (KEF) to St. Louis (STL)
Origin airport
Keflavik Intl.
Destination airport
Lambert-St. Louis Intl.
Airlines serving
Air Canada, Air France, British Airways, Delta, KLM, United, Virgin Atlantic
Roundtrip price
$751
Distance
3192 mi

Reykjavik to St. Louis Flights

The cheapest times to fly from Reykjavik to St. Louis

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Reykjavik to St. Louis are during the month of May. You can find some of the cheapest flights from Reykjavik to St. Louis with Expedia's search tool and vast selection of airlines.

The best time to book a flight from Reykjavik to St. Louis

Sunday is one of the best days to book for cheap flights from Reykjavik to St. Louis: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

How to find cheap round-trip tickets from Reykjavik to St. Louis

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Reykjavik to St. Louis in 2025. You can also book with separate airlines for your outbound and return journeys, from $666 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Reykjavik to St. Louis flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

You could also save big by booking one of Expedia's vacation packages. Bundling together your Reykjavik to St. Louis airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

*Terms apply.

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

Frequently asked questions

How much does a flight from Keflavik Intl. Airport (KEF) to Lambert-St. Louis Intl. Airport (STL) cost?
Discover the latest flight deals from KEF to STL by entering your preferred travel dates and searching on Expedia. Easily compare prices by departure date if you have flexibility with your schedule and use handy filters to explore prices for your preferred journey. As a member of One Key™, our free loyalty program, you can use Price Tracking to watch fares and receive notifications if prices go up or down.
What is the cheapest month to fly from KEF to STL?
The cheapest flights from KEF to STL are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
What is the cheapest airline that flies from KEF to STL?
Use the filter tool on Expedia to compare airlines and find the cheapest carrier that’ll take you from KEF to STL. Sort your results by “Price (lowest to highest)” to snap up a great deal.
How many flights per day from Keflavik Intl. Airport (KEF) to Lambert-St. Louis Intl. Airport (STL)?
Direct flights from Keflavik Intl. Airport (KEF) to Lambert-St. Louis Intl. Airport (STL) aren’t available daily, so you’ll have to take a flight with a layover. Explore your options with Expedia’s filter tool. Enter your dates and choose either “1 Stop” or “2+ Stops.”
What day of the week has the most flights from KEF to STL?
Typically you’ll find the most flight options available on a Friday. Tuesdays tend to be the quietest.* However, this can vary based on the season, airline and other factors.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Keflavik Intl. Airport (KEF) to Lambert-St. Louis Intl. Airport (STL)?
To reach Lambert-St. Louis Intl. Airport (STL) on time, pick a flight that leaves Keflavik Intl. Airport (KEF) before 3 PM. The chance of cancellations is 22% higher, on average, for departures after this hour.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG’s global flight data platform.
Is it cheaper to buy a plane ticket from Keflavik Intl. Airport (KEF) to Lambert-St. Louis Intl. Airport (STL) last-minute?
Holding off until just before your trip to book a ticket from KEF to STL generally means paying more. While it’s possible to find some last-minute deals, they aren’t always guaranteed. Keep your travel plans flexible for a better chance of snagging a bargain.
Is it cheaper to book a KEF to STL flight and hotel package?
You can save money by booking a KEF to STL flight and hotel package compared to booking separately. In fact, you could save hundreds of dollars by bundling with Expedia. And it’s easy to manage it all in one place. After selecting your ideal accommodations and flights, consider adding extras including activities, tours and car rentals.
Can I cancel or change the date of my flight from Keflavik Intl. Airport (KEF) to Lambert-St. Louis Intl. Airport (STL)?
In most instances, you’re able to cancel or reschedule your KEF to STL flight. However, there may be additional charges, especially if you booked over 24 hours ago. Double-check your itinerary for the airline’s fees and guidelines on flight changes, or if you need more details, go to our Customer Service portal.

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*Available to One Key members.