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Heathrow

$329+ 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 5/10. Fares are subject to change and may not be available on all flights or dates of travel.
STL — LHR
Mar 13 — Mar 201
Fri 3/13
Fri 3/20
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 April, booked 17 days in advance, depart on a Monday or Thursday and return on a Monday

Cheap 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 February 11, 2026.

This Flighttix deal was found by Cheapflights users on 2/8. 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 Flighttix is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/256:25 am
STL
-
LHR
2 stops19h 45m
Multiple Airlines
Wed 4/16:30 am
LHR
-
STL
1 stop12h 55m
Multiple Airlines
Deal found 2/8$638
This United Airlines deal was found by Cheapflights users on 2/8. 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 2/236:55 pm
STL
-
LHR
1 stop10h 20m
United Airlines
Wed 3/46:30 am
LHR
-
STL
1 stop13h 25m
United Airlines
Deal found 2/8$640
This Cheapflightsfares deal was found by Cheapflights users on 2/9. 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 8/193:30 pm
STL
-
LHR
1 stop17h 10m
Lufthansa
Wed 9/26:30 am
LHR
-
STL
1 stop12h 55m
Lufthansa
Deal found 2/9$641
This Delta deal was found by Cheapflights users on 2/8. 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 2/96:57 pm
STL
-
LHR
1 stop10h 43m
Delta
Wed 2/258:40 am
LHR
-
STL
2 stops18h 03m
Delta
Deal found 2/8$642
This Mytrip deal was found by Cheapflights users on 2/9. 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.
Wed 5/61:00 pm
STL
-
LHR
2 stops13h 35m
Multiple Airlines
Wed 5/136:30 am
LHR
-
STL
1 stop12h 55m
Multiple Airlines
Deal found 2/9$643
This United Airlines deal was found by Cheapflights users on 2/8. 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 3/1010:00 am
STL
-
LHR
2 stops16h 10m
United Airlines
Wed 3/186:50 am
LHR
-
STL
2 stops14h 33m
United Airlines
Deal found 2/8$644
This United Airlines deal was found by Cheapflights users on 2/10. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/1010:00 am
STL
-
LHR
2 stops16h 10m
United Airlines
Tue 3/176:35 am
LHR
-
STL
2 stops16h 25m
United Airlines
Deal found 2/10$645
This Delta deal was found by Cheapflights users on 2/7. 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.
Tue 2/106:35 am
STL
-
LHR
2 stops18h 30m
Delta
Tue 2/176:30 am
LHR
-
STL
2 stops16h 15m
Delta
Deal found 2/7$646
This Cheapflightsfares deal was found by Cheapflights users on 2/8. 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 8/103:30 pm
STL
-
LHR
1 stop17h 10m
Lufthansa
Thu 8/278:25 pm
LHR
-
STL
2 stops24h 56m
Lufthansa
Deal found 2/8$649

Find 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 February 11, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$643
(Mytrip)

One-way from

$329
(Trip.com)

Popular in

June

Cheapest in

October

Average price

$952

Good round-trip deal

$666 or less

Good one-way deal

$515 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. 21% potential increase in price ($237 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease ($37 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in February 2026
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 February 11, 2026.
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

Mon 3/16

7:00 pm-5:55 am

1 stop29h 55m

London Heathrow

Thu 3/26

9:00 am-3:29 pm

2 stops35h 29m

$655

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 4/22

6:15 am-10:00 am

2 stops21h 45m

London Heathrow

Wed 4/29

10:50 am-9:08 pm

2 stops16h 18m

$656

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Mon 3/30

12:04 pm-6:45 am

1 stop12h 41m

London Heathrow

Tue 4/7

6:30 am-5:53 pm

2 stops17h 23m

$657

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Mon 3/30

4:21 pm-1:15 pm

1 stop14h 54m

London Heathrow

Tue 4/14

6:30 am-4:42 pm

2 stops16h 12m

$657

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Sat 4/11

4:05 pm-9:00 pm

2 stops22h 55m

London Heathrow

Wed 4/22

6:50 am-9:47 pm

2 stops20h 57m

$661

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Mon 5/4

1:00 pm-10:00 am

1 stop15h 00m

London Heathrow

Thu 5/21

7:30 am-10:44 pm

2 stops21h 14m

$667

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Mon 4/13

10:50 am-8:50 am

2 stops16h 00m

London Heathrow

Tue 4/28

6:15 am-5:44 pm

2 stops17h 29m

$669

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 5/6

7:45 am-11:45 am

1 stop22h 00m

London Heathrow

Thu 5/21

5:40 pm-12:06 pm

1 stop24h 26m

$672

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Tue 5/5

4:06 pm-9:40 am

1 stop35h 34m

London Heathrow

Tue 5/19

5:40 pm-8:04 pm

1 stop32h 24m

$672

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Mon 3/30

6:05 pm-9:40 am

1 stop33h 35m

London Heathrow

Tue 4/14

5:40 pm-3:24 pm

1 stop27h 44m

$672

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/10

Showing 1-10 of 17 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 February.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
OvagoPrice Accuracy2 starsTrust Score*3 stars
AranGrantPrice Accuracy2 starsTrust Score*2 stars
JustAirTicketPrice 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 FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on St. Louis-London Heathrow Airport flight deals on Cheapflights vs. FlightHub >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 FlightHub the most. FlightHub 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 February 6, 2026.

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 17 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, February is the cheapest month in which you can book a flight from St. Louis to London Heathrow Airport (average of $529). Flying from St. Louis to London Heathrow Airport in June is currently the most expensive (average of $999). 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.

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 February 11, 2026.
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
9,274 reviews

Crew

8.1

Overall

7.4

Comfort

7.3

Boarding

7.7

Entertainment

7.1

Food

6.6

Reviews

1 / 20
10.0
Excellent

Dane,Jan 2026

TYS - IAD

It was a short flight, so no time for amenities. Just glad everything was quick and easy from boarding to arriving at my destination with my family
United Airlines
7.4
Good
9,274 reviews
United Airlines
7.4
Good
9,274 reviews

Crew

8.1

Overall

7.4

Comfort

7.3

Boarding

7.7

Entertainment

7.1

Food

6.6

Reviews

1 / 20
10.0
Excellent

Dane,Jan 2026

TYS - IAD

It was a short flight, so no time for amenities. Just glad everything was quick and easy from boarding to arriving at my destination with my family
American Airlines
7.2
Good
11,266 reviews
United Airlines
7.4
Good
9,274 reviews

Crew

8.1

Overall

7.4

Comfort

7.3

Boarding

7.7

Entertainment

7.1

Food

6.6

Reviews

1 / 20
10.0
Excellent

Dane,Jan 2026

TYS - IAD

It was a short flight, so no time for amenities. Just glad everything was quick and easy from boarding to arriving at my destination with my family
Air Canada
7.1
Good
10,707 reviews
United Airlines
7.4
Good
9,274 reviews

Crew

8.1

Overall

7.4

Comfort

7.3

Boarding

7.7

Entertainment

7.1

Food

6.6

Reviews

1 / 20
10.0
Excellent

Dane,Jan 2026

TYS - IAD

It was a short flight, so no time for amenities. Just glad everything was quick and easy from boarding to arriving at my destination with my family
Iberia
7.0
Good
3,112 reviews
United Airlines
7.4
Good
9,274 reviews

Crew

8.1

Overall

7.4

Comfort

7.3

Boarding

7.7

Entertainment

7.1

Food

6.6

Reviews

1 / 20
10.0
Excellent

Dane,Jan 2026

TYS - IAD

It was a short flight, so no time for amenities. Just glad everything was quick and easy from boarding to arriving at my destination with my family
British Airways
6.7
Okay
7,728 reviews
United Airlines
7.4
Good
9,274 reviews

Crew

8.1

Overall

7.4

Comfort

7.3

Boarding

7.7

Entertainment

7.1

Food

6.6

Reviews

1 / 20
10.0
Excellent

Dane,Jan 2026

TYS - IAD

It was a short flight, so no time for amenities. Just glad everything was quick and easy from boarding to arriving at my destination with my family

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?

    United Airlines and Delta can get you from St. Louis to London Heathrow Airport in just under 12h 41m. Your travel time can differ by up to 17h 14m. 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 ($572), and British Airways ($574) offers the cheapest pricing from St. Louis to London Heathrow Airport. KLM is 38% 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 British Airways. According to our data, you can fly for as low as $397. Users have also found prices from $418 and $446 on Delta and American Airlines, respectively.

  • 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 $1,084, our data shows the cheapest flight currently is $354. When looking at the most popular route, (Lambert-St Louis - London Heathrow), you can expect to pay $619 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, February is the cheapest month in which you can book a flight from St. Louis to London Heathrow Airport (average of $529). Flying from St. Louis to London Heathrow Airport in June is currently the most expensive (average of $999). 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
Ilford
Croydon
Hounslow
Southend-on-Sea
Harrow
Eastleigh
Gatwick
Dartford
Dover
Winchester
Orpington
Northampton
Watford
Hayes
Borehamwood
Broadway
Aylesbury
Chipping Norton
Horley
Kingston upon Thames

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 February 11, 2026.
AirlineCheapestAverageFlexibilityOn-time
KLMCheapest$529Average$683FlexibilityNo cancel feeOn-time75%
Air CanadaCheapest$572Average$964FlexibilityNo cancel feeOn-time67%
British AirwaysCheapest$574Average$836FlexibilityNo cancel feeOn-time70%
DeltaCheapest$577Average$946FlexibilityNo cancel feeOn-timeN/A
IberiaCheapest$580Average$979FlexibilityNo cancel feeOn-time77%
United AirlinesCheapest$580Average$856FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$596Average$886FlexibilityNo cancel feeOn-time71%
Scandinavian AirlinesCheapest$602Average$1,114FlexibilityNo cancel feeOn-time77%
Virgin AtlanticCheapest$615Average$965FlexibilityNo cancel feeOn-time72%
LufthansaCheapest$668Average$898FlexibilityNo cancel feeOn-time76%

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