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Keflavik Intl

$500+ 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 8/27. Fares are subject to change and may not be available on all flights or dates of travel.
STL — KEF
Jun 17 — Jun 241
Tue 6/17
Tue 6/24
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 June 12, 2025.

Round-trip from

$596
(Mytrip)

One-way from

$500
(United Airlines)

Popular in

June

Cheapest in

May

Average price

$1,210
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. 4% potential increase in price ($44 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 June 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 June 12, 2025.

This Mytrip deal was found by Cheapflights users on 6/10. 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.
Fri 8/228:44 amSTL - KEF
1 stop16h 41mMultiple Airlines
Sun 8/244:55 pmKEF - STL
1 stop19h 54mMultiple Airlines
Deal found 6/10$596
This KLM deal was found by Cheapflights users on 6/11. 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.
Wed 8/1311:02 amSTL - KEF
2 stops17h 28mKLM
Wed 8/2011:25 amKEF - STL
2 stops15h 37mKLM
Deal found 6/11$604
This Travelocity deal was found by Cheapflights users on 6/10. 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.
Wed 11/126:29 pmSTL - KEF
2 stops34h 26mBritish Airways
Wed 11/1911:45 amKEF - STL
2 stops38h 15mBritish Airways
Deal found 6/10$620
This Air Canada deal was found by Cheapflights users on 6/12. 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.
Wed 8/131:30 pmSTL - KEF
2 stops37h 45mAir Canada
Thu 8/219:30 amKEF - STL
1 stop15h 30mAir Canada
Deal found 6/12$642
This United Airlines deal was found by Cheapflights users on 6/12. 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.
Wed 8/131:30 pmSTL - KEF
1 stop13h 40mUnited Airlines
Thu 8/219:30 amKEF - STL
1 stop15h 30mUnited Airlines
Deal found 6/12$660
This Delta deal was found by Cheapflights users on 6/11. 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 8/36:00 amSTL - KEF
2 stops19h 20mDelta
Wed 8/1311:25 amKEF - STL
2 stops25h 47mDelta
Deal found 6/11$684
This Lufthansa deal was found by Cheapflights users on 6/10. 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 6/10$758
This FlightHub deal was found by Cheapflights users on 6/12. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/1312:20 pmSTL - KEF
2 stops30h 00mAustrian Airlines
Fri 9/2612:10 amKEF - STL
2 stops28h 37mAustrian Airlines
Deal found 6/12$959

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 June 12, 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

Fri 8/22

8:44 am-6:25 am

1 stop16h 41m

Reykjavik Keflavik Intl

Sun 8/24

4:55 pm-7:49 am

1 stop19h 54m

$596

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Wed 8/13

11:02 am-9:30 am

2 stops17h 28m

Reykjavik Keflavik Intl

Wed 8/20

11:25 am-10:02 pm

2 stops15h 37m

$604

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Wed 11/12

6:29 pm-10:55 am

2 stops34h 26m

Reykjavik Keflavik Intl

Wed 11/19

11:45 am-8:00 pm

2 stops38h 15m

$620

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Wed 8/13

1:30 pm-8:15 am

2 stops37h 45m

Reykjavik Keflavik Intl

Thu 8/21

9:30 am-8:00 pm

1 stop15h 30m

$642

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Wed 8/13

1:30 pm-8:10 am

1 stop13h 40m

Reykjavik Keflavik Intl

Thu 8/21

9:30 am-8:00 pm

1 stop15h 30m

$660

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Sun 8/3

6:40 am-6:20 am

1 stop18h 40m

Reykjavik Keflavik Intl

Wed 8/13

11:25 am-12:31 pm

2 stops30h 06m

$684

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Sun 8/24

5:30 pm-11:35 pm

2 stops25h 05m

Reykjavik Keflavik Intl

Sun 8/31

12:25 am-3:44 pm

2 stops20h 19m

$758

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Sat 9/13

12:20 pm-11:20 pm

2 stops30h 00m

Reykjavik Keflavik Intl

Fri 9/26

12:10 am-11:47 pm

2 stops28h 37m

$959

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Wed 8/27

7:25 am-8:10 am

2 stops19h 45m

$500

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Wed 8/27

4:00 pm-8:15 am

1 stop11h 15m

$502

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/10

Showing 1-10 of 12 results
1
2

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 $659). 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 June 12, 2025.
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Overall

8.0

Boarding

8.1

Food

7.1

Crew

8.5

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Surinder,May 2025

SEA - YYZ

My wife wanted the aile seat and I always prefer window seat. Luckily we both got the best seats we wanted. The plane was very nice and we enjoyed the best take off and the smooth landing at Toronto. All the services by the staff inside the aeroplane were very nice well appreciated. Thanks again and hope to see you soon.
Alaska Airlines
8.0
Very good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Overall

8.0

Boarding

8.1

Food

7.1

Crew

8.5

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Surinder,May 2025

SEA - YYZ

My wife wanted the aile seat and I always prefer window seat. Luckily we both got the best seats we wanted. The plane was very nice and we enjoyed the best take off and the smooth landing at Toronto. All the services by the staff inside the aeroplane were very nice well appreciated. Thanks again and hope to see you soon.
Delta
8.0
Very good
7,946 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Overall

8.0

Boarding

8.1

Food

7.1

Crew

8.5

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Surinder,May 2025

SEA - YYZ

My wife wanted the aile seat and I always prefer window seat. Luckily we both got the best seats we wanted. The plane was very nice and we enjoyed the best take off and the smooth landing at Toronto. All the services by the staff inside the aeroplane were very nice well appreciated. Thanks again and hope to see you soon.
KLM
7.8
Good
1,358 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Overall

8.0

Boarding

8.1

Food

7.1

Crew

8.5

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Surinder,May 2025

SEA - YYZ

My wife wanted the aile seat and I always prefer window seat. Luckily we both got the best seats we wanted. The plane was very nice and we enjoyed the best take off and the smooth landing at Toronto. All the services by the staff inside the aeroplane were very nice well appreciated. Thanks again and hope to see you soon.
Austrian Airlines
7.6
Good
802 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Overall

8.0

Boarding

8.1

Food

7.1

Crew

8.5

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Surinder,May 2025

SEA - YYZ

My wife wanted the aile seat and I always prefer window seat. Luckily we both got the best seats we wanted. The plane was very nice and we enjoyed the best take off and the smooth landing at Toronto. All the services by the staff inside the aeroplane were very nice well appreciated. Thanks again and hope to see you soon.
United Airlines
7.4
Good
8,790 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Overall

8.0

Boarding

8.1

Food

7.1

Crew

8.5

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Surinder,May 2025

SEA - YYZ

My wife wanted the aile seat and I always prefer window seat. Luckily we both got the best seats we wanted. The plane was very nice and we enjoyed the best take off and the smooth landing at Toronto. All the services by the staff inside the aeroplane were very nice well appreciated. Thanks again and hope to see you soon.

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 KLM. Our recent data shows that you can find tickets from as low as $604 on this airline. Additional options worth looking into are British Airways and Air Canada, starting at $620 and $642 round-trip. KLM is 35% 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?

    $500 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 Air Canada and Alaska Airlines, with prices starting from $502 and $2,102, 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 $659). 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.

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Alternative routes for St. Louis to Keflavik Intl

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Kansas City to Keflavik Intl flights
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 June 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapest$566Average$729FlexibilityNo cancel feeOn-time67%
United AirlinesCheapest$595Average$1,071FlexibilityNo cancel feeOn-time69%
DeltaCheapest$636Average$980FlexibilityNo cancel feeOn-timeN/A
KLMCheapest$828Average$1,157FlexibilityNo cancel feeOn-time75%

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