What is the cheapest airline that flies from Lambert-St Louis to London Heathrow?

United Airlines is the most popular carrier operating from Lambert-St Louis to London Heathrow

Which layover airport has the shortest connection time from St. Louis to London Heathrow Airport?

Atlanta (ATL) has the shortest average layover time for this route: 1h 49m.

What airlines fly to London Heathrow Airport?

British Airways, American Airlines and United Airlines are the top three most popular airlines that fly to London Heathrow Airport from St. Louis according to our data. British Airways is the first choice among our users, with 42% of people opting to fly with this airline when traveling to London Heathrow Airport. Keep in mind that there are 9 different airlines that fly to London Heathrow Airport on a routine basis, so you have a few additional options to choose from.

Which layover airport has the shortest travel time from St. Louis to London Heathrow Airport?

Flights connecting via Chicago (ORD) have the shortest average one-way travel time: 10h 51m.

Which airport is the most popular layover for flights between St. Louis and London Heathrow Airport?

Chicago (ORD) was the most common stop: 40% of momondo users choosing 1-stop flights on this route connected there.

Which layover airport offers the lowest fares from St. Louis to London Heathrow Airport?

Flights via Philadelphia (PHL) offer the lowest average round-trip price of $703.

When did momondo last update prices for flights from Lambert-St Louis Airport to London Heathrow Airport?

Prices for flights from Lambert-St Louis Airport to London Heathrow Airport were last updated today.

How many operators does momondo search for flights from Lambert-St Louis Airport to London Heathrow Airport?

As of February 2026, there are 9 operators available to choose from for flights from Lambert-St Louis Airport to London Heathrow Airport.

How old do you have to be to fly from Lambert-St Louis Airport to London Heathrow Airport?

Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Lambert-St Louis Airport to London Heathrow Airport.

What documentation or ID do you need to fly to London Heathrow Airport?

The necessary travel and health documents for your London Heathrow Airport trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.

$324 Cheap Flights from St. Louis to London Heathrow Airport in 2026

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Find the cheapest flights from St. Louis to London

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One-way

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Cheap round-trip flights

Enter your travel dates to find the best prices.

3:30 pm - 5:40 pm

STL

LHR

20h 10m

1 stop

8:25 pm - 3:38 pm

LHR

STL

25h 13m

2 stops

$648Lufthansa

Sun, Aug 16 - Tue, Aug 25

12:25 pm - 10:35 am

STL

LHR

16h 10m

2 stops

6:15 am - 10:17 pm

LHR

STL

22h 02m

2 stops

$651Iberia

Tue, Apr 7 - Tue, Apr 14

6:49 pm - 6:25 pm

STL

LHR

17h 36m

2 stops

7:30 pm - 1:25 pm

LHR

STL

23h 55m

1 stop

$652Lufthansa

Mon, Aug 17 - Mon, Aug 24

6:49 pm - 5:40 pm

STL

LHR

16h 51m

2 stops

6:30 am - 3:38 pm

LHR

STL

15h 08m

2 stops

$653Lufthansa

Wed, Aug 19 - Fri, Aug 28

4:05 pm - 9:00 pm

STL

LHR

22h 55m

2 stops

8:40 am - 8:25 pm

LHR

STL

17h 45m

2 stops

$654Air Canada

Sun, Apr 26 - Wed, May 6

6:00 am - 7:15 am

STL

LHR

19h 15m

1 stop

6:30 am - 4:42 pm

LHR

STL

16h 12m

2 stops

$656Delta

Mon, Mar 30 - Tue, Apr 14

7:45 am - 6:30 am

STL

LHR

16h 45m

2 stops

12:10 pm - 3:24 pm

LHR

STL

57h 14m

2 stops

$658Air Canada

Wed, Apr 8 - Mon, Apr 13

4:05 pm - 9:35 am

STL

LHR

11h 30m

1 stop

8:30 am - 3:24 pm

LHR

STL

12h 54m

1 stop

$659Air Canada

Tue, Apr 7 - Tue, Apr 14

9:45 am - 7:10 am

STL

LHR

15h 25m

2 stops

9:55 am - 11:25 pm

LHR

STL

19h 30m

2 stops

$660Delta

Mon, Mar 30 - Fri, Apr 10

5:59 pm - 1:45 pm

STL

LHR

13h 46m

2 stops

6:30 am - 4:16 pm

LHR

STL

15h 46m

2 stops

$661Delta

Mon, Mar 30 - Wed, Apr 8

Iberia flights from St. Louis to London Heathrow Airport

Our best Iberia deals on St. Louis to London Heathrow Airport flight tickets

Iberia

Apr 19

STL8:03 pmLambert-St Louis

10h 12m

1 stop

LHR12:15 pmLondon Heathrow

Apr 29

LHR4:25 pmLondon Heathrow

9h 05m

STL7:30 pmLambert-St Louis

$668

Iberia

Apr 21

STL6:11 pmLambert-St Louis

11h 59m

1 stop

LHR12:10 pmLondon Heathrow

Apr 28

LHR12:15 pmLondon Heathrow

13h 18m

1 stop

STL7:33 pmLambert-St Louis

$683

Iberia

Apr 22

STL12:25 pmLambert-St Louis

13h 15m

1 stop

LHR7:40 amLondon Heathrow

Apr 29

LHR6:15 amLondon Heathrow

19h 18m

2 stops

STL7:33 pmLambert-St Louis

$696

Air Canada flights from St. Louis to London Heathrow Airport

Our best Air Canada deals on St. Louis to London Heathrow Airport flight tickets

Air Canada

Mar 1

STL4:05 pmLambert-St Louis

46h 30m

2 stops

LHR8:35 pmLondon Heathrow

Mar 13

LHR6:00 pmLondon Heathrow

27h 23m

2 stops

STL4:23 pmLambert-St Louis

$657

Air Canada

Apr 7

STL4:05 pmLambert-St Louis

11h 30m

1 stop

LHR9:35 amLondon Heathrow

Apr 14

LHR8:30 amLondon Heathrow

12h 54m

1 stop

STL3:24 pmLambert-St Louis

$659

Air Canada

Mar 1

STL4:05 pmLambert-St Louis

22h 30m

2 stops

LHR8:35 pmLondon Heathrow

Mar 13

LHR6:00 pmLondon Heathrow

29h 00m

2 stops

STL6:00 pmLambert-St Louis

$677

momondo Fare Finder

Use the filters below to find and compare flights from St. Louis to London Heathrow Airport that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Sun 8/16

3:30 pm-5:40 pm

1 stop20h 10m

London Heathrow

Tue 8/25

8:25 pm-3:38 pm

2 stops25h 13m

$648

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Tue 4/7

12:25 pm-10:35 am

2 stops16h 10m

London Heathrow

Tue 4/14

6:15 am-10:17 pm

2 stops22h 02m

$651

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Mon 8/17

6:49 pm-6:25 pm

2 stops17h 36m

London Heathrow

Mon 8/24

7:30 pm-1:25 pm

1 stop23h 55m

$652

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 8/19

6:49 pm-5:40 pm

2 stops16h 51m

London Heathrow

Fri 8/28

6:30 am-3:38 pm

2 stops15h 08m

$653

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Sun 4/26

4:05 pm-9:00 pm

2 stops22h 55m

London Heathrow

Wed 5/6

8:40 am-8:25 pm

2 stops17h 45m

$654

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Mon 3/30

6:00 am-7:15 am

1 stop19h 15m

London Heathrow

Tue 4/14

6:30 am-4:42 pm

2 stops16h 12m

$656

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 4/8

7:45 am-6:30 am

2 stops16h 45m

London Heathrow

Mon 4/13

12:10 pm-3:24 pm

2 stops57h 14m

$658

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Tue 4/7

4:05 pm-9:35 am

1 stop11h 30m

London Heathrow

Tue 4/14

8:30 am-3:24 pm

1 stop12h 54m

$659

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Mon 3/30

9:45 am-7:10 am

2 stops15h 25m

London Heathrow

Fri 4/10

9:55 am-11:25 pm

2 stops19h 30m

$660

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Mon 3/30

5:59 pm-1:45 pm

2 stops13h 46m

London Heathrow

Wed 4/8

6:30 am-4:16 pm

2 stops15h 46m

$661

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

How to get the cheapest flight ticket from St. Louis to London Heathrow Airport

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

Prices

Airlines

Layovers

What is the cheapest month to fly to London Heathrow Airport?

The month of October is, on average, the cheapest month to fly to London Heathrow Airport from St. Louis, with most prices found around $671. If you’re not able to fly to London Heathrow Airport in October, then April is your next best option. Flight prices from St. Louis to London Heathrow Airport during April average around $700.

What is the cheapest day to depart on your flight to London Heathrow Airport?

Our data shows that Monday is the least expensive day to fly to London Heathrow Airport. Tickets to fly out on this day can be as low as $688. The most expensive day to fly to London Heathrow Airport is Saturday, with ticket prices averaging around $989.

What is the cheapest Lambert-St Louis to London Heathrow flight route?

Fly from Lambert-St Louis to London Heathrow for the best Lambert-St Louis - London Heathrow flight prices

How far in advance should I book a flight to London Heathrow Airport?

You are more likely to see cheaper flights to London Heathrow Airport from St. Louis when booking weeks ahead of your departure date. In general, you can expect to find flights to London Heathrow Airport for around $859 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to London Heathrow Airport from St. Louis for as low as $786 on momondo.

What cabin class options are available on Lambert-St Louis to London Heathrow flights?

There are 3 cabin classes available to choose from on Lambert-St Louis to London Heathrow flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on St. Louis to London Heathrow Airport flights?

You could potentially save up to 2% on your flight if you consider stops on a St. Louis to London Heathrow Airport flight.

How have St. Louis to London Heathrow Airport flight prices changed over time?

As of February 2026, prices for St. Louis to London Heathrow Airport flights are approximately 15% cheaper when compared to flights at the same time last year.

When to book flights from St. Louis to London Heathrow Airport

Are you open to changing your travel dates? Check out the ideal times to fly from St. Louis to London Heathrow Airport according to our flight data. Find out which month and days have the cheapest flights.

Estimated round-trip price

Cheap St. Louis to London Heathrow Airport (STL to LHR) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from St. Louis to London Heathrow Airport

Best Price Found	$436
Fastest flight time	8h 00m
Direct flights	Mon, Wed, Thu and Sat

The best one-way flight to London Heathrow Airport from St. Louis in the past 72 hours is $436. The best round-trip flight deal from St. Louis to London Heathrow Airport found on momondo in the last 72 hours is $797.

The fastest flight from St. Louis to London Heathrow Airport takes 8h 00m

Direct flights go from St. Louis to London Heathrow Airport on Monday, Wednesday, Thursday and Saturday. There are no airlines offering direct flights.

Search flight deals

How far is Lambert-St Louis to London Heathrow by plane?
Lambert-St Louis and London Heathrow are 4185.8 mi apart from one another. By plane, this route typically takes 8h 00m.
When did momondo last update prices for flights from Lambert-St Louis Airport to London Heathrow Airport?
Prices for flights from Lambert-St Louis Airport to London Heathrow Airport were last updated today.
How many operators does momondo search for flights from Lambert-St Louis Airport to London Heathrow Airport?
As of February 2026, there are 9 operators available to choose from for flights from Lambert-St Louis Airport to London Heathrow Airport.
How old do you have to be to fly from Lambert-St Louis Airport to London Heathrow Airport?
Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Lambert-St Louis Airport to London Heathrow Airport.
What documentation or ID do you need to fly to London Heathrow Airport?
The necessary travel and health documents for your London Heathrow Airport trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.
What is the most popular plane model from St. Louis to London Heathrow Airport?
Based on momondo bookings for flights between St. Louis and London Heathrow Airport, the leading plane model is Boeing 787-8 Dreamliner, making up 94.79% of the total bookings. Other popular models include Boeing 787-9 Dreamliner with 4.65% and Airbus A330-300 with 0.56%.
What is the most popular airline from St. Louis to London Heathrow Airport?
momondo data reveals that the most frequently booked airline on the route from St. Louis to London Heathrow Airport is British Airways, representing 34% of all bookings. The subsequent popular airlines are American Airlines at 22%, United Airlines at 18%, and Iberia at 9%.

Best airlines flying from St. Louis to London Heathrow Airport

Compare and see reviews for airlines that fly from St. Louis to London Heathrow Airport with momondo

Airline	Rating	Free Cancellation	Price
KLM	PriceFrom $529	Free Cancellation	Rating 7.7 1,460 reviews	Search KLM flights
British Airways	PriceFrom $538	Free Cancellation	Rating 6.7 7,770 reviews	Search British Airways flights
Air Canada	PriceFrom $572	Free Cancellation	Rating 7.1 10,748 reviews	Search Air Canada flights
Delta	PriceFrom $577	Free Cancellation	Rating 7.9 8,240 reviews	Search Delta flights
Iberia	PriceFrom $580	Free Cancellation	Rating 7.0 3,127 reviews	Search Iberia flights
United Airlines	PriceFrom $580	Free Cancellation	Rating 7.4 9,348 reviews	Search United Airlines flights
American Airlines	PriceFrom $596	Free Cancellation	Rating 7.2 11,352 reviews	Search American Airlines flights
Scandinavian Airlines	PriceFrom $602	Free Cancellation	Rating 7.3 1,700 reviews	Search Scandinavian Airlines flights
Lufthansa	PriceFrom $668	Free Cancellation	Rating 6.8 7,814 reviews	Search Lufthansa flights

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Crawley

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Dartford

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Watford

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Romford

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Why use momondo?

Why should I use momondo to find a flight deal from St. Louis to London?

To find the flight that best suits your needs, momondo gathers a range of flights from a large pool of different airlines and agents; you can then use our insights and filters to find and book the right flight to London from St. Louis.

Can I find flights from St. Louis to London with flexible booking policies on momondo?

Flights from St. Louis to London with flexible booking policies can be found by using the search form above and then selecting our dedicated flexible booking filter, which will highlight only the flights where this policy is applied.

How can momondo help me find flights from St. Louis to London?

Once all potential St. Louis to London flight options are in front of you, momondo lets you sort and filter flights based on preferences such as airline, price and flight times amongst many other options.

I’m not ready to book a flight from St. Louis to London right now. Can momondo alert me if prices change?

Yes momondo offers price alerts on flights to London from St. Louis. After performing a search on this page you should be able to see the price alert set up feature. Simply provide a valid email address and momondo will instantly alert you when prices change.

An easier way to manage your London Heathrow Airport trip

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Flights to London Gatwick Airportfrom $352

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Cheap flights from St. Louis to London from $324

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from St. Louis to London departing on 3/23. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

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Iberia flights from St. Louis to London Heathrow Airport

Our best Iberia deals on St. Louis to London Heathrow Airport flight tickets

Air Canada flights from St. Louis to London Heathrow Airport

Our best Air Canada deals on St. Louis to London Heathrow Airport flight tickets

momondo Fare Finder

Use the filters below to find and compare flights from St. Louis to London Heathrow Airport that are best for you.

See travel insights to London from

How to get the cheapest flight ticket from St. Louis to London Heathrow Airport

What is the cheapest month to fly to London Heathrow Airport?

What is the cheapest day to depart on your flight to London Heathrow Airport?

What is the cheapest Lambert-St Louis to London Heathrow flight route?

How far in advance should I book a flight to London Heathrow Airport?

What cabin class options are available on Lambert-St Louis to London Heathrow flights?

Can stopping save me money on St. Louis to London Heathrow Airport flights?

How have St. Louis to London Heathrow Airport flight prices changed over time?

What is the cheapest airline that flies from Lambert-St Louis to London Heathrow?

What airlines fly to London Heathrow Airport?

Which airport is the most popular layover for flights between St. Louis and London Heathrow Airport?

Which layover airport offers the lowest fares from St. Louis to London Heathrow Airport?

Which layover airport has the shortest travel time from St. Louis to London Heathrow Airport?

Which layover airport has the shortest connection time from St. Louis to London Heathrow Airport?

When to book flights from St. Louis to London Heathrow Airport

Cheap St. Louis to London Heathrow Airport (STL to LHR) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from St. Louis to London Heathrow Airport

Best Price Found

Fastest flight time

Direct flights

Best airlines flying from St. Louis to London Heathrow Airport

Compare and see reviews for airlines that fly from St. Louis to London Heathrow Airport with momondo

Traveling to a place near London?

Why use momondo?

An easier way to manage your London Heathrow Airport trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.

Find better results for your trip to London

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According to popular flight searches on momondo this year

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List of cabin classes available on flights landing in London. Availability may vary depending on flight origin and airline.

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