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Keflavik Intl

$403+ Cheap flights from St. Louis (STL) to Keflavik Intl (KEF)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 6/19. Fares are subject to change and may not be available on all flights or dates of travel.
STL — KEF
May 20 — May 271
Tue 5/20
Tue 5/27
1 adult, Economy
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Cheap flight deals from St. Louis to Keflavik Intl

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Keflavik Intl (KEF). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated May 15, 2025.

Most accurate provider

AranGrant
3 stars

Most trusted provider

AranGrant
3 stars

Round-trip from

$615
(Air Canada)

One-way from

$403
(Mytrip)

Popular in

June

Cheapest in

May

Average price

$736
Provider with most accurate pricing for Lambert-St Louis-Reykjavik Keflavik Intl flight deals.
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Provider most trusted by Cheapflights users for Lambert-St Louis-Reykjavik Keflavik Intl flights.
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From Lambert-St Louis to Reykjavik Keflavik Intl
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One-way flight from Lambert-St Louis to Reykjavik Keflavik Intl
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Highest demand for flights based on searches. 3% potential increase in price ($32 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($26 potential savings vs. average RT price).
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Average for round-trip flights in May 2025
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Find flight deals from St. Louis to Keflavik Intl

Cheapest flights from St. Louis to Keflavik Intl
Explore the most affordable flight options available from St. Louis to Keflavik Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 15, 2025.

This Air Canada deal was found by Cheapflights users on 5/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/51:30 pmSTL - KEF
1 stop13h 40mAir Canada
Fri 8/159:50 amKEF - STL
2 stops33h 47mAir Canada
Deal found 5/15$615
This United Airlines deal was found by Cheapflights users on 5/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/256:35 amSTL - KEF
1 stop20h 55mUnited Airlines
Thu 9/49:50 amKEF - STL
3 stops35h 50mUnited Airlines
Deal found 5/14$621
This Delta deal was found by Cheapflights users on 5/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/33:16 pmSTL - KEF
1 stop13h 14mDelta
Wed 8/138:50 amKEF - STL
1 stop9h 26mDelta
Deal found 5/15$636
This KLM deal was found by Cheapflights users on 5/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/302:18 pmSTL - KEF
1 stop11h 02mKLM
Tue 10/78:45 amKEF - STL
1 stop16h 50mKLM
Deal found 5/15$661
This Mytrip deal was found by Cheapflights users on 5/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/237:13 pmSTL - KEF
2 stops28h 32mMultiple Airlines
Wed 7/29:35 amKEF - STL
3 stops36h 29mMultiple Airlines
Deal found 5/15$669
This Travelocity deal was found by Cheapflights users on 5/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Travelocity is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/307:23 amSTL - KEF
2 stops29h 12mBritish Airways
Sat 11/811:50 amKEF - STL
2 stops38h 10mBritish Airways
Deal found 5/15$723
This Lufthansa deal was found by Cheapflights users on 5/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Lufthansa is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/245:30 pmSTL - KEF
2 stops25h 05mLufthansa
Sun 8/3112:25 amKEF - STL
2 stops20h 19mLufthansa
Deal found 5/15$818
This Finnair deal was found by Cheapflights users on 5/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Finnair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/151:54 pmSTL - KEF
2 stops37h 06mFinnair
Mon 10/208:45 amKEF - STL
2 stops38h 33mFinnair
Deal found 5/15$950

Cheapflights Fare Finder

Customize your flight search to find flights from St. Louis to Keflavik Intl 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, Cheapflights users made 2,558,603 searches. Data last updated May 15, 2025.
Use the filters below to find and compare flights from St. Louis to Reykjavik Keflavik Intl Airport that are best for you.

Fly from

St. Louis

Fly to

Keflavik Intl

Route

Depart

Return

Price

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Tue 8/5

1:30 pm-8:10 am

1 stop13h 40m

Reykjavik Keflavik Intl

Fri 8/15

9:50 am-2:37 pm

2 stops33h 47m

$615

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Tue 8/5

1:30 pm-8:10 am

1 stop13h 40m

Reykjavik Keflavik Intl

Thu 8/14

9:50 am-7:40 pm

1 stop14h 50m

$628

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Sun 8/3

3:16 pm-9:30 am

1 stop13h 14m

Reykjavik Keflavik Intl

Wed 8/13

8:50 am-1:16 pm

1 stop9h 26m

$636

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Mon 6/23

7:13 pm-4:45 am

2 stops28h 32m

Reykjavik Keflavik Intl

Wed 7/2

9:35 am-5:04 pm

3 stops36h 29m

$662

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Mon 8/4

3:42 pm-9:30 am

2 stops12h 48m

Reykjavik Keflavik Intl

Tue 8/12

8:50 am-3:58 pm

2 stops12h 08m

$706

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Mon 8/4

10:46 am-6:20 am

2 stops14h 34m

Reykjavik Keflavik Intl

Mon 8/11

9:30 am-4:45 pm

1 stop12h 15m

$776

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Tue 8/5

4:52 pm-8:00 am

2 stops34h 08m

Reykjavik Keflavik Intl

Thu 8/14

5:15 pm-11:03 pm

2 stops34h 48m

$1,048

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Thu 8/7

8:35 am-9:10 am

2 stops43h 35m

Reykjavik Keflavik Intl

Fri 8/15

8:45 am-11:03 pm

2 stops19h 18m

$1,143

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Sun 6/29

5:30 pm-11:35 pm

2 stops25h 05m

Reykjavik Keflavik Intl

Sat 7/5

12:25 am-10:45 pm

2 stops27h 20m

$1,467

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Thu 7/3

1:30 pm-3:20 pm

2 stops20h 50m

Reykjavik Keflavik Intl

Sun 7/13

1:00 am-11:53 pm

3 stops27h 53m

$1,739

Flights are sorted by cheapest round-trip flights first.

Deals found on 5/15

Showing 1-10 of 13 results
1
2

Compare providers for flights from St. Louis to Keflavik Intl

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from St. Louis to Keflavik Intl in May.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*2 stars
AranGrantPrice Accuracy3 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on St. Louis-Reykjavik Keflavik Intl Airport flights, users find the pricing of AranGrant to be most consistent on Cheapflights vs. AranGrant Users can find the same prices on St. Louis-Reykjavik Keflavik Intl Airport flight deals on Cheapflights vs. AranGrant >95% of the time. Price accuracy is based on data collected from St. Louis-Reykjavik Keflavik Intl Airport flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on St. Louis-Reykjavik Keflavik Intl Airport flights, Cheapflights users trust AranGrant the most. AranGrant has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for St. Louis-Reykjavik Keflavik Intl Airport flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from St. Louis to Keflavik Intl

Have a flexible travel schedule? Discover the best time to fly to Keflavik Intl from St. Louis with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from St. Louis to Reykjavik Keflavik Intl Airport

What is the cheapest month to book a flight from St. Louis to Reykjavik Keflavik Intl Airport?

Currently, November is the cheapest month in which you can book a flight from St. Louis to Reykjavik Keflavik Intl Airport (average of $328). Flying from St. Louis to Reykjavik Keflavik Intl Airport in June is currently the most expensive (average of $653). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

Rainfall in Keflavik Intl by month

Plan your trip to Keflavik Intl by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Reykjavik Keflavik Intl Airport ranges from 1.6 - 3.1 inches per month. January is typically the wettest month, when rainfall can reach 3.1 in. May is typically the driest time to visit Reykjavik Keflavik Intl Airport when rainfall is around 1.6 in.

Temperature in Keflavik Intl by month

Plan your trip to Keflavik Intl by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Reykjavik Keflavik Intl Airport, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 51.8 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 32.0 F).

Reviews of airlines servicing Keflavik Intl

Get insights into the airlines that provide service to Keflavik Intl. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Keflavik Intl. Reviews last updated May 15, 2025.
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Boarding

8.2

Comfort

7.9

Food

7.1

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Alaska Airlines
8.0
Very good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Boarding

8.2

Comfort

7.9

Food

7.1

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Delta
8.0
Very good
7,946 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Boarding

8.2

Comfort

7.9

Food

7.1

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
KLM
7.8
Good
1,344 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Boarding

8.2

Comfort

7.9

Food

7.1

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Finnair
7.6
Good
1,279 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Boarding

8.2

Comfort

7.9

Food

7.1

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
United Airlines
7.4
Good
8,731 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Boarding

8.2

Comfort

7.9

Food

7.1

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Keflavik Intl. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly from for flights from St. Louis to Reykjavik Keflavik Intl?

    Located just 12.7 mi from the city center, Lambert-St Louis is the airport most travelers will use when flying to Reykjavik Keflavik Intl from St. Louis. Booking flights from Lambert-St Louis (STL) to Reykjavik Keflavik Intl should be relatively easy as there are 0 daily outbound flights to Reykjavik Keflavik Intl from 4 different airlines.

  • What are the cheapest airlines flying from St. Louis to Reykjavik Keflavik Intl Airport round-trip?

    Our cheapest airline available from St. Louis to Reykjavik Keflavik Intl Airport is Air Canada. Our recent data shows that you can find tickets from as low as $615 on this airline. Additional options worth looking into are United Airlines and Delta, starting at $621 and $636 round-trip. Air Canada is 33% cheaper than the average price of flights available within the next 90 days to this destination.

  • What are the cheapest airlines to fly from St. Louis to Reykjavik Keflavik Intl Airport one-way?

    $745 is the cheapest one-way deal found within the past few days, from United Airlines. You may also be able to find cheap deals on Alaska Airlines and British Airways, with prices starting from $2,432 and $3,455, respectively.

  • Can I find deals for flights from St. Louis to Keflavik Intl that include hotel bookings?

    Yes. In addition to deals on St. Louis to Keflavik Intl flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from St. Louis to Keflavik Intl?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to Keflavik Intl.

  • Can I find deals for business class flights from St. Louis to Keflavik Intl?

    Yes. Cheapflights offers flight deals from St. Louis to Keflavik Intl by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from St. Louis to Reykjavik Keflavik Intl Airport?

    Currently, November is the cheapest month in which you can book a flight from St. Louis to Reykjavik Keflavik Intl Airport (average of $328). Flying from St. Louis to Reykjavik Keflavik Intl Airport in June is currently the most expensive (average of $653). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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Keflavik

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Alternative routes for St. Louis to Keflavik Intl

See prices for flight routes from nearby airports that may be better suited for you.
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Springfield to Keflavik Intl flights

Top 4 airlines flying from St. Louis to Keflavik Intl

Discover the top 4 airlines that operate flights from St. Louis to Keflavik Intl. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated May 15, 2025.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapest$566Average$699FlexibilityNo cancel feeOn-time67%
United AirlinesCheapest$595Average$1,104FlexibilityNo cancel feeOn-time69%
DeltaCheapest$651Average$987FlexibilityNo cancel feeOn-timeN/A
KLMCheapest$856Average$1,182FlexibilityNo cancel feeOn-time75%

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