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$403+ Cheap flights from St. Louis (STL) to Heathrow (LHR)

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 5/27. Fares are subject to change and may not be available on all flights or dates of travel.
STL — LHR
Apr 20 — Apr 271
Sun 4/20
Sun 4/27
1 adult, Economy
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Cheapflights Tip: The best prices from Lambert-St Louis to London Heathrow are usually found in October or January, booked 56 days in advance, depart on a Thursday or Tuesday and return on a Thursday

Cheap flight deals from St. Louis to Heathrow

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Heathrow (LHR). 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 April 15, 2025.

Most accurate provider

AranGrant
3 stars

Most trusted provider

AranGrant
3 stars

Round-trip from

$704
(Air Canada)

One-way from

$403
(Kiwi.com)

Popular in

June

Cheapest in

October

Average price

$841
Provider with most accurate pricing for Lambert-St Louis-London Heathrow flight deals.
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Provider most trusted by Cheapflights users for Lambert-St Louis-London Heathrow flights.
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From Lambert-St Louis to London Heathrow
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One-way flight from Lambert-St Louis to London Heathrow
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Highest demand for flights based on searches. 14% potential increase in price ($164 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($25 potential savings vs. average RT price).
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Average for round-trip flights in April 2025
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Find flight deals from St. Louis to Heathrow

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

This Air Canada deal was found by Cheapflights users on 4/14. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/149:15 amSTL - LHR
2 stops15h 15mAir Canada
Wed 10/222:05 pmLHR - STL
2 stops31h 11mAir Canada
Deal found 4/14$703
This Air Canada deal was found by Cheapflights users on 4/14. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/132:30 pmSTL - LHR
2 stops13h 30mMultiple Airlines
Wed 6/410:30 amLHR - STL
2 stops15h 28mMultiple Airlines
Deal found 4/14$704
This Delta deal was found by Cheapflights users on 4/14. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/1711:51 amSTL - LHR
2 stops15h 04mDelta
Wed 9/248:40 amLHR - STL
2 stops17h 55mDelta
Deal found 4/14$707
This United deal was found by Cheapflights users on 4/14. 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 is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/121:30 pmSTL - LHR
1 stop14h 30mUnited Airlines
Fri 5/236:30 amLHR - STL
1 stop13h 00mUnited Airlines
Deal found 4/14$711
This KLM deal was found by Cheapflights users on 4/14. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/1911:51 amSTL - LHR
1 stop12h 54mKLM
Thu 8/281:05 pmLHR - STL
1 stop13h 42mKLM
Deal found 4/14$715
This Cheapflightsfares deal was found by Cheapflights users on 4/14. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/92:42 pmSTL - LHR
1 stop11h 23mIberia
Mon 9/223:30 pmLHR - STL
1 stop14h 19mIberia
Deal found 4/14$719
This Virgin Atlantic deal was found by Cheapflights users on 4/14. 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 Virgin Atlantic is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/143:40 pmSTL - LHR
2 stops13h 45mVirgin Atlantic
Tue 6/179:20 amLHR - STL
1 stop12h 58mVirgin Atlantic
Deal found 4/14$727
This FlightHub deal was found by Cheapflights users on 4/14. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/143:30 pmSTL - LHR
2 stops18h 30mScandinavian Airlines
Wed 8/206:40 amLHR - STL
2 stops22h 59mScandinavian Airlines
Deal found 4/14$738
This Cheapflightsfares deal was found by Cheapflights users on 4/13. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/255:30 pmSTL - LHR
2 stops19h 10mLufthansa
Thu 9/46:30 amLHR - STL
2 stops15h 14mLufthansa
Deal found 4/13$768
This Cheapflightsfares deal was found by Cheapflights users on 4/14. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/23:29 pmSTL - LHR
1 stop9h 51mBritish Airways
Sun 5/119:15 amLHR - STL
1 stop12h 12mBritish Airways
Deal found 4/14$791
This StudentUniverse deal was found by Cheapflights users on 4/14. 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 StudentUniverse is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/139:47 amSTL - LHR
2 stops18h 33mAer Lingus
Sat 10/181:25 pmLHR - STL
2 stops16h 00mAer Lingus
Deal found 4/14$1,042

Cheapflights Fare Finder

Customize your flight search to find flights from St. Louis to Heathrow 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 April 15, 2025.
Use the filters below to find and compare flights from St. Louis to London Heathrow Airport that are best for you.

Fly from

St. Louis

Fly to

Heathrow

Route

Depart

Return

Price

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Tue 5/13

2:30 pm-10:00 am

2 stops13h 30m

London Heathrow

Wed 6/4

10:30 am-7:58 pm

2 stops15h 28m

$704

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 9/17

11:51 am-8:55 am

2 stops15h 04m

London Heathrow

Wed 9/24

8:40 am-8:35 pm

2 stops17h 55m

$707

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Mon 5/12

1:30 pm-10:00 am

1 stop14h 30m

London Heathrow

Fri 5/23

6:30 am-1:30 pm

1 stop13h 00m

$711

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Tue 8/19

11:51 am-6:45 am

1 stop12h 54m

London Heathrow

Thu 8/28

1:05 pm-8:47 pm

1 stop13h 42m

$715

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Tue 9/9

2:42 pm-8:05 am

1 stop11h 23m

London Heathrow

Mon 9/22

3:30 pm-11:49 pm

1 stop14h 19m

$719

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 8/20

1:30 pm-8:35 am

2 stops13h 05m

London Heathrow

Thu 8/28

9:30 am-8:00 pm

1 stop16h 30m

$725

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 5/14

3:40 pm-11:25 am

2 stops13h 45m

London Heathrow

Tue 6/17

9:20 am-4:18 pm

1 stop12h 58m

$727

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Thu 8/14

3:30 pm-4:00 pm

2 stops18h 30m

London Heathrow

Wed 8/20

6:40 am-11:39 pm

2 stops22h 59m

$738

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Mon 8/25

5:30 pm-6:40 pm

2 stops19h 10m

London Heathrow

Thu 9/4

6:30 am-3:44 pm

2 stops15h 14m

$768

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Fri 5/2

3:29 pm-7:20 am

1 stop9h 51m

London Heathrow

Sun 5/11

9:15 am-3:27 pm

1 stop12h 12m

$791

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/13

Showing 1-10 of 18 results
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Compare providers for flights from St. Louis to Heathrow

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 Heathrow in April.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*2 stars
AranGrantPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
CheapflightsfaresPrice Accuracy3 starsTrust Score*2 stars
OvagoPrice Accuracy3 starsTrust Score*2 stars
CheapfaremartPrice Accuracy-Trust Score*1 star

*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-London Heathrow 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-London Heathrow Airport flight deals on Cheapflights vs. AranGrant >95% of the time. Price accuracy is based on data collected from St. Louis-London Heathrow Airport flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on St. Louis-London Heathrow 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-London Heathrow 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 Heathrow

Have a flexible travel schedule? Discover the best time to fly to Heathrow 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 London Heathrow Airport

How far ahead should I book a flight from St. Louis to London Heathrow Airport?

Use this chart to determine the optimal time to book a round-trip flight from St. Louis to Heathrow. Price data was last updated on April 11, 2025.

To ensure you get the cheapest price possible for a flight from St. Louis to London Heathrow Airport, you should look to book at least 56 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

What is the cheapest month to book a flight from St. Louis to London Heathrow Airport?

Currently, November is the cheapest month in which you can book a flight from St. Louis to London Heathrow Airport (average of $661). Flying from St. Louis to London Heathrow Airport in June is currently the most expensive (average of $1,110). 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.

What is the cheapest time of day to fly from STL to LHR?

Find hourly flight availability from St. Louis to Heathrow. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated April 15, 2025.

One of the essential ways to save on airfare from St. Louis to London Heathrow Airport is to remain as flexible as possible. Flights that are in the morning tend to be the most expensive. A flight in the evening could potentially save you up to 11% on airfare.

Rainfall in Heathrow by month

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

In terms of precipitation, rainfall in London Heathrow Airport ranges from 1.6 - 2.8 inches per month. January is typically the wettest month, when rainfall can reach 2.8 in. July is typically the driest time to visit London Heathrow Airport when rainfall is around 1.6 in.

Temperature in Heathrow by month

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

If weather is an important factor for your trip to London Heathrow 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 62.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 39.2 F).

Reviews of airlines servicing Heathrow

Get insights into the airlines that provide service to Heathrow. 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 Heathrow. Reviews last updated April 15, 2025.
Get a feel of what it's like to fly with Delta, KLM and Finnair from St. Louis to London by reading reviews from past customers. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,917 reviews

Food

7.3

Comfort

7.9

Crew

8.5

Entertainment

7.9

Boarding

8.2

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
Delta
8.0
Very good
7,917 reviews
Delta
8.0
Very good
7,917 reviews

Food

7.3

Comfort

7.9

Crew

8.5

Entertainment

7.9

Boarding

8.2

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
KLM
7.8
Good
1,323 reviews
Delta
8.0
Very good
7,917 reviews

Food

7.3

Comfort

7.9

Crew

8.5

Entertainment

7.9

Boarding

8.2

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
Finnair
7.6
Good
1,269 reviews
Delta
8.0
Very good
7,917 reviews

Food

7.3

Comfort

7.9

Crew

8.5

Entertainment

7.9

Boarding

8.2

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
United Airlines
7.4
Good
8,656 reviews
Delta
8.0
Very good
7,917 reviews

Food

7.3

Comfort

7.9

Crew

8.5

Entertainment

7.9

Boarding

8.2

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
Virgin Atlantic
7.4
Good
642 reviews
Delta
8.0
Very good
7,917 reviews

Food

7.3

Comfort

7.9

Crew

8.5

Entertainment

7.9

Boarding

8.2

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Heathrow. 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 London Heathrow?

    Located just 12.7 mi from the city center, Lambert-St Louis is the airport most travelers will use when flying to London Heathrow from St. Louis. Booking flights from Lambert-St Louis (STL) to London Heathrow should be relatively easy as there are 0 daily outbound flights to London Heathrow from 10 different airlines.

  • What are the cheapest airlines flying from St. Louis to London Heathrow Airport round-trip?

    According to our current data, Delta ($708), United Airlines ($711), and Virgin Atlantic ($727) offers the cheapest pricing from St. Louis to London Heathrow Airport. Delta is 25% 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 London Heathrow Airport one-way?

    For one-way options, check prices for Iberia. According to our data, you can fly for as low as $463. Users have also found prices from $465 and $474 on Aer Lingus and Air Canada, respectively.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from St. Louis to Heathrow 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 London Heathrow Airport?

    Currently, November is the cheapest month in which you can book a flight from St. Louis to London Heathrow Airport (average of $661). Flying from St. Louis to London Heathrow Airport in June is currently the most expensive (average of $1,110). 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
Hayes
Hounslow
Thornton Heath
Luton
Horley
Wembley
Canterbury
Harrow
Dover
Stratford-upon-Avon
Gatwick
Orpington
Watford
Northampton
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Borehamwood
Folkestone
Ilford
Broadway
Aylesbury

Browse thousands of different options on Cheapflights for your next trip

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Top 10 airlines flying from St. Louis to Heathrow

Discover the top 10 airlines that operate flights from St. Louis to Heathrow. 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 April 15, 2025.
AirlineCheapestAverageFlexibilityOn-time
Scandinavian AirlinesCheapest$669Average$1,102FlexibilityNo cancel feeOn-time77%
IberiaCheapest$671Average$928FlexibilityNo cancel feeOn-time77%
British AirwaysCheapest$705Average$986FlexibilityNo cancel feeOn-time70%
United AirlinesCheapest$718Average$961FlexibilityNo cancel feeOn-time69%
KLMCheapest$726Average$896FlexibilityNo cancel feeOn-time75%
DeltaCheapest$726Average$930FlexibilityNo cancel feeOn-timeN/A
Virgin AtlanticCheapest$727Average$915FlexibilityNo cancel feeOn-time72%
Air CanadaCheapest$728Average$980FlexibilityNo cancel feeOn-time67%
LufthansaCheapest$734Average$1,076FlexibilityNo cancel feeOn-time76%
American AirlinesCheapest$744Average$1,053FlexibilityNo cancel feeOn-time71%

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