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Heathrow

$315+ 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 12/10. Fares are subject to change and may not be available on all flights or dates of travel.
STL — LHR
Dec 24 — Dec 311
Wed 12/24
Wed 12/31
1 adult, Economy
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Find cheap flights from St. Louis to Heathrow with Cheapflights

1. Tell us where you want to go

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Cheapflights Tip: The best prices from Lambert-St Louis to London Heathrow are usually found in October or November, booked 27 days in advance, depart on a Monday or Thursday and return on a Thursday

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 November 24, 2025.

This Kiwi.com deal was found by Cheapflights users on 11/23. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/31:00 pmSTL - LHR
1 stop10h 55mAustrian Airlines
Mon 12/810:25 amLHR - STL
1 stop12h 38mAustrian Airlines
Deal found 11/23$655
This Air Canada deal was found by Cheapflights users on 11/22. 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 12/34:05 pmSTL - LHR
1 stop10h 25mAir Canada
Fri 12/1212:00 pmLHR - STL
2 stops16h 45mAir Canada
Deal found 11/22$656
This Cheapflightsfares deal was found by Cheapflights users on 11/22. 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.
Wed 12/311:50 amSTL - LHR
1 stop12h 30mLufthansa
Sun 12/77:30 amLHR - STL
2 stops20h 10mLufthansa
Deal found 11/22$669
This Kiwi.com deal was found by Cheapflights users on 11/22. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/411:50 amSTL - LHR
1 stop14h 35mAustrian Airlines
Thu 12/114:00 pmLHR - STL
1 stop13h 42mAustrian Airlines
Deal found 11/22$670
This Orbitz deal was found by Cheapflights users on 11/23. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/36:42 pmSTL - LHR
2 stops15h 08mLufthansa
Mon 12/88:30 amLHR - STL
2 stops38h 33mLufthansa
Deal found 11/23$674
This United Airlines deal was found by Cheapflights users on 11/23. 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.
Tue 12/28:30 amSTL - LHR
2 stops16h 40mUnited Airlines
Sun 12/76:50 amLHR - STL
2 stops14h 50mUnited Airlines
Deal found 11/23$676
This United Airlines deal was found by Cheapflights users on 11/23. 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.
Sun 11/304:05 pmSTL - LHR
2 stops22h 30mUnited Airlines
Sun 12/76:50 amLHR - STL
2 stops14h 50mUnited Airlines
Deal found 11/23$678
This KAYAK deal was found by Cheapflights users on 11/23. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/411:50 amSTL - LHR
1 stop15h 20mLufthansa
Wed 12/107:40 amLHR - STL
2 stops15h 23mLufthansa
Deal found 11/23$680
This Virgin Atlantic deal was found by Cheapflights users on 11/23. 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 12/311:40 amSTL - LHR
2 stops14h 10mVirgin Atlantic
Mon 12/86:30 amLHR - STL
2 stops15h 36mVirgin Atlantic
Deal found 11/23$681
This FlightHub deal was found by Cheapflights users on 11/23. 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.
Wed 12/310:13 amSTL - LHR
1 stop15h 07mBritish Airways
Mon 12/87:40 pmLHR - STL
2 stops30h 44mBritish Airways
Deal found 11/23$682
This Cheapflightsfares deal was found by Cheapflights users on 11/23. 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 12/21:00 pmSTL - LHR
1 stop10h 55mLufthansa
Sun 12/710:25 amLHR - STL
1 stop12h 38mLufthansa
Deal found 11/23$686
This Cheapflightsfares deal was found by Cheapflights users on 11/24. 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.
Sun 11/306:43 pmSTL - LHR
2 stops17h 02mLufthansa
Sun 12/77:30 amLHR - STL
2 stops20h 10mLufthansa
Deal found 11/24$687

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 November 24, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$655
(Kiwi.com)

One-way from

$315
(Kiwi.com)

Popular in

June

Cheapest in

October

Average price

$751

Good round-trip deal

$598 or less

Good one-way deal

$418 or less
Provider with most accurate pricing for Lambert-St Louis-London Heathrow flight deals.
Search Deals
Provider most trusted by Cheapflights users for Lambert-St Louis-London Heathrow flights.
Search Deals
From Lambert-St Louis to London Heathrow
Search Deals
One-way flight from Lambert-St Louis to London Heathrow
Search Deals
Highest demand for flights based on searches. 17% potential increase in price ($192 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($32 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in November 2025
Search Deals
Price to beat on a round-trip flight from Lambert-St Louis to London Heathrow.
Search Deals
Price to beat on a one-way flight from Lambert-St Louis to London Heathrow.
Search Deals

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 November 24, 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 1/6

4:05 pm-8:30 am

1 stop10h 25m

London Heathrow

Wed 1/14

1:00 pm-3:29 pm

1 stop32h 29m

$660

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 1/7

1:15 pm-7:55 am

1 stop12h 40m

London Heathrow

Tue 1/13

4:00 pm-11:59 pm

1 stop13h 59m

$661

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 1/7

5:59 pm-11:05 am

1 stop11h 06m

London Heathrow

Thu 1/15

10:25 am-5:43 pm

1 stop13h 18m

$661

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Fri 12/5

1:00 pm-7:55 am

1 stop12h 55m

London Heathrow

Wed 12/10

6:30 am-1:55 pm

1 stop13h 25m

$676

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Sun 11/30

3:14 pm-7:55 am

1 stop10h 41m

London Heathrow

Sun 12/7

6:50 am-7:17 pm

2 stops18h 27m

$676

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Tue 12/2

8:30 am-7:10 am

2 stops16h 40m

London Heathrow

Sun 12/7

6:50 am-3:40 pm

2 stops14h 50m

$676

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Thu 1/22

1:15 pm-5:55 am

1 stop10h 40m

London Heathrow

Wed 2/4

11:05 am-9:13 pm

2 stops16h 08m

$683

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 2/4

10:19 am-8:45 am

1 stop16h 26m

London Heathrow

Sun 2/8

11:45 am-8:43 pm

2 stops14h 58m

$684

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Sun 11/30

6:43 pm-5:45 pm

2 stops17h 02m

London Heathrow

Sun 12/7

7:30 am-9:40 pm

2 stops20h 10m

$687

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 12/10

3:30 pm-10:50 am

3 stops37h 20m

$315

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/23

Showing 1-10 of 16 results
1
2

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 November.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
eDreamsPrice Accuracy3 starsTrust Score*3 stars
AranGrantPrice Accuracy2 starsTrust Score*3 stars
CheapflightsfaresPrice 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 eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on St. Louis-London Heathrow Airport flight deals on Cheapflights vs. eDreams >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 eDreams the most. eDreams 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 November 21, 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 27 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, September is the cheapest month in which you can book a flight from St. Louis to London Heathrow Airport (average of $530). Flying from St. Louis to London Heathrow Airport in June is currently the most expensive (average of $1,001). 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 November 24, 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 21% on airfare.

What is the cheapest day to fly from St. Louis to London Heathrow Airport?

Use this chart to determine the cheapest time to fly round-trip from St. Louis to Heathrow. Price data was last updated on December 16, 2024.

Travelers seeking maximum savings on their St. Louis to London Heathrow Airport flight should consider departing on Monday evenings when fares are most often at their lowest. Sunday mornings flights should be avoided if possible as fares are typically the most expensive at this time.

How much does it cost to fly round-trip from St. Louis to London Heathrow Airport?

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 November 24, 2025.
Get a feel of what it's like to fly with United Airlines, American Airlines, and Air Canada from St. Louis to London Heathrow Airport by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
9,038 reviews

Boarding

7.7

Entertainment

7.1

Comfort

7.3

Crew

8.1

Overall

7.4

Food

6.6

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
United Airlines
7.4
Good
9,038 reviews
United Airlines
7.4
Good
9,038 reviews

Boarding

7.7

Entertainment

7.1

Comfort

7.3

Crew

8.1

Overall

7.4

Food

6.6

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
American Airlines
7.2
Good
11,040 reviews
United Airlines
7.4
Good
9,038 reviews

Boarding

7.7

Entertainment

7.1

Comfort

7.3

Crew

8.1

Overall

7.4

Food

6.6

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
Air Canada
7.1
Good
10,466 reviews
United Airlines
7.4
Good
9,038 reviews

Boarding

7.7

Entertainment

7.1

Comfort

7.3

Crew

8.1

Overall

7.4

Food

6.6

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
Iberia
7.0
Good
3,033 reviews
United Airlines
7.4
Good
9,038 reviews

Boarding

7.7

Entertainment

7.1

Comfort

7.3

Crew

8.1

Overall

7.4

Food

6.6

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
British Airways
6.7
Okay
7,535 reviews
United Airlines
7.4
Good
9,038 reviews

Boarding

7.7

Entertainment

7.1

Comfort

7.3

Crew

8.1

Overall

7.4

Food

6.6

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000

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.

  • How long is the flight from St. Louis to London Heathrow Airport?

    Air Canada, Austrian Airlines, and United Airlines can get you from St. Louis to London Heathrow Airport in just under 10h 25m. Your travel time can differ by up to 2h 15m. Airlines will cover a distance of 4186 mi. Both multi-stop and nonstop flights can be found to your destination and back.

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

    According to our current data, KLM ($529), Air Canada ($573), and Delta ($580) offers the cheapest pricing from St. Louis to London Heathrow Airport. KLM is 41% cheaper than the average price of flights available within the next 90 days to this destination.

  • What are the cheapest flights from St. Louis to London Heathrow Airport?

    While on average a flight from St. Louis to London Heathrow Airport is generally $1,174, our data shows the cheapest flight currently is $403. When looking at the most popular route, (Lambert-St Louis - London Heathrow), you can expect to pay $597 for that flight.

  • 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, September is the cheapest month in which you can book a flight from St. Louis to London Heathrow Airport (average of $530). Flying from St. Louis to London Heathrow Airport in June is currently the most expensive (average of $1,001). 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 London Heathrow Airport?

Book flights to London Heathrow Airport if you plan to visit one of these locations
Hounslow
Ilford
Hayes
Southend-on-Sea
Harrow
Croydon
Eastleigh
Dartford
Dover
Winchester
Orpington
Northampton
Gatwick
Borehamwood
Broadway
Aylesbury
Bedford
Chipping Norton
Wembley
Folkestone

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

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 November 24, 2025.
AirlineCheapestAverageFlexibilityOn-time
KLMCheapest$529Average$745FlexibilityNo cancel feeOn-time75%
Air CanadaCheapest$573Average$929FlexibilityNo cancel feeOn-time67%
DeltaCheapest$580Average$925FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$580Average$886FlexibilityNo cancel feeOn-time69%
British AirwaysCheapest$581Average$886FlexibilityNo cancel feeOn-time70%
IberiaCheapest$597Average$960FlexibilityNo cancel feeOn-time77%
Scandinavian AirlinesCheapest$602Average$1,102FlexibilityNo cancel feeOn-time77%
American AirlinesCheapest$636Average$899FlexibilityNo cancel feeOn-time71%
LufthansaCheapest$670Average$888FlexibilityNo cancel feeOn-time76%
Virgin AtlanticCheapest$747Average$947FlexibilityNo cancel feeOn-time72%

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