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Keflavik Intl

$349+ 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 8/21. Fares are subject to change and may not be available on all flights or dates of travel.
STL — KEF
Jul 8 — Jul 151
Tue 7/8
Tue 7/15
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 July 3, 2025.

Round-trip from

$581
(Mytrip)

One-way from

$349
(Mytrip)

Popular in

June

Cheapest in

May

Average price

$973
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 July 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 July 3, 2025.

This Mytrip deal was found by Cheapflights users on 7/1. 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 8/181:00 pmSTL - KEF
2 stops12h 40mMultiple Airlines
Sun 8/247:35 pmKEF - STL
2 stops21h 35mMultiple Airlines
Deal found 7/1$581
This Expedia deal was found by Cheapflights users on 7/1. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/106:29 pmSTL - KEF
2 stops34h 21mBritish Airways
Thu 11/2011:40 amKEF - STL
2 stops38h 20mBritish Airways
Deal found 7/1$622
This United Airlines deal was found by Cheapflights users on 7/2. 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.
Fri 8/221:30 pmSTL - KEF
1 stop13h 50mUnited Airlines
Tue 8/269:50 amKEF - STL
2 stops29h 50mUnited Airlines
Deal found 7/2$631
This Gotogate deal was found by Cheapflights users on 7/2. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/121:30 pmSTL - KEF
2 stops37h 45mAir Canada
Tue 8/269:50 amKEF - STL
2 stops33h 43mAir Canada
Deal found 7/2$637
This KLM deal was found by Cheapflights users on 7/1. 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 8/1911:23 amSTL - KEF
1 stop14h 37mKLM
Tue 8/268:50 amKEF - STL
1 stop12h 57mKLM
Deal found 7/1$651
This Delta deal was found by Cheapflights users on 7/3. 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.
Mon 8/255:25 pmSTL - KEF
1 stop7h 55mDelta
Thu 9/49:30 amKEF - STL
1 stop18h 53mDelta
Deal found 7/3$681
This Lufthansa deal was found by Cheapflights users on 7/2. 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.
Wed 10/1512:25 pmSTL - KEF
2 stops30h 45mLufthansa
Sun 10/1912:25 amKEF - STL
2 stops44h 19mLufthansa
Deal found 7/2$770

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 July 3, 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

Mon 8/18

1:00 pm-6:40 am

2 stops12h 40m

Reykjavik Keflavik Intl

Sun 8/24

7:35 pm-12:10 pm

2 stops21h 35m

$581

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Mon 11/10

6:29 pm-10:50 am

2 stops34h 21m

Reykjavik Keflavik Intl

Thu 11/20

11:40 am-8:00 pm

2 stops38h 20m

$622

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Fri 8/22

1:30 pm-8:20 am

1 stop13h 50m

Reykjavik Keflavik Intl

Tue 8/26

9:50 am-10:40 am

2 stops29h 50m

$631

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Tue 8/12

1:30 pm-8:15 am

2 stops37h 45m

Reykjavik Keflavik Intl

Tue 8/26

9:50 am-2:33 pm

2 stops33h 43m

$637

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Tue 8/19

11:23 am-7:00 am

1 stop14h 37m

Reykjavik Keflavik Intl

Tue 8/26

8:50 am-4:47 pm

1 stop12h 57m

$651

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Mon 8/25

5:25 pm-6:20 am

1 stop7h 55m

Reykjavik Keflavik Intl

Thu 9/4

9:30 am-11:23 pm

1 stop18h 53m

$681

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Wed 10/15

12:25 pm-12:10 am

2 stops30h 45m

Reykjavik Keflavik Intl

Sun 10/19

12:25 am-3:44 pm

2 stops44h 19m

$770

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Thu 8/21

10:37 am-4:55 am

3 stops37h 18m

$349

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Wed 8/27

1:30 pm-8:10 am

1 stop13h 40m

$495

St. LouisReykjavik

STL - KEF

STLKEF

Lambert-St Louis

Wed 8/27

8:10 am-8:10 am

2 stops19h 00m

$500

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/3

Showing 1-10 of 13 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 $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.

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 July 3, 2025.
See what other customers who have flown with Delta, KLM, and Air France from St. Louis to Reykjavik Keflavik Intl Airport have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,982 reviews

Overall

8.0

Food

7.3

Comfort

7.9

Boarding

8.2

Entertainment

7.9

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
Delta
8.0
Very good
7,982 reviews
Delta
8.0
Very good
7,982 reviews

Overall

8.0

Food

7.3

Comfort

7.9

Boarding

8.2

Entertainment

7.9

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
KLM
7.8
Good
1,367 reviews
Delta
8.0
Very good
7,982 reviews

Overall

8.0

Food

7.3

Comfort

7.9

Boarding

8.2

Entertainment

7.9

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
Air France
7.5
Good
1,465 reviews
Delta
8.0
Very good
7,982 reviews

Overall

8.0

Food

7.3

Comfort

7.9

Boarding

8.2

Entertainment

7.9

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
United Airlines
7.4
Good
8,861 reviews
Delta
8.0
Very good
7,982 reviews

Overall

8.0

Food

7.3

Comfort

7.9

Boarding

8.2

Entertainment

7.9

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
WestJet
7.2
Good
2,917 reviews
Delta
8.0
Very good
7,982 reviews

Overall

8.0

Food

7.3

Comfort

7.9

Boarding

8.2

Entertainment

7.9

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

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 British Airways. Our recent data shows that you can find tickets from as low as $622 on this airline. Additional options worth looking into are United Airlines and Air Canada, starting at $631 and $637 round-trip. British Airways 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?

    $495 is the cheapest one-way deal found within the past few days, from Air Canada. You may also be able to find cheap deals on United Airlines and Air France, with prices starting from $500 and $550, 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

Traveling to a place near St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
Keflavik
Hveragerdi

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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 July 3, 2025.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapest$566Average$729FlexibilityNo cancel feeOn-time67%
United AirlinesCheapest$586Average$1,108FlexibilityNo cancel feeOn-time69%
DeltaCheapest$636Average$1,002FlexibilityNo cancel feeOn-timeN/A
KLMCheapest$828Average$1,157FlexibilityNo cancel feeOn-time75%

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