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.

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

Montreal (YUL) has the shortest average layover time for this route: 1h 55m.

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

Virgin Atlantic, United Airlines, and Air Canada are the most popular carriers operating from Lambert-St Louis to London Heathrow

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

Chicago (ORD) was the most common stop: 50% of momondo users choosing 1-stop flights on this route connected there.

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

Flights connecting via Montreal (YUL) have the shortest average one-way travel time: 11h 00m.

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 44% of people opting to fly with this airline when traveling to London Heathrow Airport. Keep in mind that there are 8 different airlines that fly to London Heathrow Airport on a routine basis, so you have a few additional options to choose from.

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 April 2026, there are 8 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.

$429 Cheap Flights from St. Louis to London Heathrow Airport in 2026

Q: What is the typical price of a round-trip flight between St. Louis and London Heathrow Airport?

Prices are currently low for flights on this route. Typical prices usually range from $841 to $635. The lowest price recently found on this route was $822.

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Find the cheapest flights from St. Louis to London

Round-trip

One-way

Last minute

Direct

Cheap round-trip flights

Enter your travel dates to find the best prices.

1:30 pm - 9:40 pm

STL

LHR

26h 10m

2 stops

6:40 am - 11:37 pm

LHR

STL

22h 57m

2 stops

$822Scandinavian Airlines

Sun, Sep 6 - Sat, Sep 12

3:42 pm - 5:40 pm

STL

LHR

19h 58m

2 stops

6:40 am - 8:50 pm

LHR

STL

20h 10m

2 stops

$823Scandinavian Airlines

Sun, Sep 6 - Sat, Sep 12

3:42 pm - 9:40 pm

STL

LHR

23h 58m

2 stops

6:40 am - 11:37 pm

LHR

STL

22h 57m

2 stops

$830Scandinavian Airlines

Sun, Sep 6 - Mon, Sep 14

12:10 pm - 8:35 am

STL

LHR

14h 25m

2 stops

5:15 pm - 6:42 pm

LHR

STL

31h 27m

2 stops

$831Air Canada

Wed, Aug 26 - Wed, Sep 2

1:30 pm - 6:30 pm

STL

LHR

23h 00m

2 stops

9:05 pm - 8:49 pm

LHR

STL

29h 44m

3 stops

$835Scandinavian Airlines

Mon, Oct 5 - Fri, Oct 16

3:30 pm - 10:40 am

STL

LHR

13h 10m

1 stop

6:30 am - 1:25 pm

LHR

STL

12h 55m

1 stop

$836Lufthansa

Tue, Oct 6 - Wed, Oct 14

12:10 pm - 10:00 am

STL

LHR

15h 50m

1 stop

6:30 am - 1:25 pm

LHR

STL

12h 55m

1 stop

$838Air Canada

Wed, Aug 26 - Wed, Sep 2

1:30 pm - 5:40 pm

STL

LHR

22h 10m

2 stops

5:00 pm - 8:50 pm

LHR

STL

33h 50m

2 stops

$839Scandinavian Airlines

Sun, Sep 6 - Fri, Sep 18

3:42 pm - 9:20 am

STL

LHR

35h 38m

2 stops

5:00 pm - 11:39 pm

LHR

STL

36h 39m

2 stops

$840Scandinavian Airlines

Mon, Aug 17 - Sat, Jan 16

3:30 pm - 5:40 pm

STL

LHR

20h 10m

1 stop

7:10 pm - 3:38 pm

LHR

STL

26h 28m

2 stops

$845Lufthansa

Wed, Oct 7 - Tue, Oct 13

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

Aug 26

STL12:10 pmLambert-St Louis

14h 25m

2 stops

LHR8:35 amLondon Heathrow

Sep 2

LHR5:15 pmLondon Heathrow

31h 27m

2 stops

STL6:42 pmLambert-St Louis

$831

Air Canada

Aug 26

STL12:10 pmLambert-St Louis

15h 50m

1 stop

LHR10:00 amLondon Heathrow

Sep 2

LHR6:30 amLondon Heathrow

12h 55m

1 stop

STL1:25 pmLambert-St Louis

$838

Air Canada

May 10

STL1:05 pmLambert-St Louis

11h 25m

1 stop

LHR6:30 amLondon Heathrow

May 19

LHR9:30 amLondon Heathrow

16h 55m

1 stop

STL8:25 pmLambert-St Louis

$858

United Airlines flights from St. Louis to London Heathrow Airport

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

United Airlines

May 5

STL6:15 amLambert-St Louis

18h 15m

2 stops

LHR6:30 amLondon Heathrow

May 12

LHR6:50 amLondon Heathrow

15h 49m

2 stops

STL4:39 pmLambert-St Louis

$870

United Airlines

Apr 21

STL6:15 amLambert-St Louis

21h 45m

2 stops

LHR10:00 amLondon Heathrow

May 7

LHR6:50 amLondon Heathrow

15h 49m

2 stops

STL4:39 pmLambert-St Louis

$871

United Airlines

Aug 19

STL12:10 pmLambert-St Louis

12h 20m

1 stop

LHR6:30 amLondon Heathrow

Aug 24

LHR5:50 pmLondon Heathrow

27h 48m

2 stops

STL3:38 pmLambert-St Louis

$884

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

Cheapest round-trip

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Sun 9/6

1:30 pm-9:40 pm

2 stops26h 10m

London Heathrow

Sat 9/12

6:40 am-11:37 pm

2 stops22h 57m

$822

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Sun 9/6

3:42 pm-5:40 pm

2 stops19h 58m

London Heathrow

Sat 9/12

6:40 am-8:50 pm

2 stops20h 10m

$823

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Sun 9/6

3:42 pm-9:40 pm

2 stops23h 58m

London Heathrow

Mon 9/14

6:40 am-11:37 pm

2 stops22h 57m

$830

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 8/26

12:10 pm-8:35 am

2 stops14h 25m

London Heathrow

Wed 9/2

5:15 pm-6:42 pm

2 stops31h 27m

$831

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Mon 10/5

1:30 pm-6:30 pm

2 stops23h 00m

London Heathrow

Fri 10/16

9:05 pm-8:49 pm

3 stops29h 44m

$835

Quickest round-trip

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Tue 10/6

3:30 pm-10:40 am

1 stop13h 10m

London Heathrow

Wed 10/14

6:30 am-1:25 pm

1 stop12h 55m

$836

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 8/26

12:10 pm-10:00 am

1 stop15h 50m

London Heathrow

Wed 9/2

6:30 am-1:25 pm

1 stop12h 55m

$838

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Sun 9/6

1:30 pm-5:40 pm

2 stops22h 10m

London Heathrow

Fri 9/18

5:00 pm-8:50 pm

2 stops33h 50m

$839

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Mon 8/17

3:42 pm-9:20 am

2 stops35h 38m

London Heathrow

Sat 1/16

5:00 pm-11:39 pm

2 stops36h 39m

$840

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 10/7

3:30 pm-5:40 pm

1 stop20h 10m

London Heathrow

Tue 10/13

7:10 pm-3:38 pm

2 stops26h 28m

$845

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 typical price of a round-trip flight between St. Louis and London Heathrow Airport?

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 $658. If you’re not able to fly to London Heathrow Airport in October, then November is your next best option. Flight prices from St. Louis to London Heathrow Airport during November average around $703.

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 $693. The most expensive day to fly to London Heathrow Airport is Saturday, with ticket prices averaging around $1,101.

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 $845 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 $680 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?

No. A direct flight is the cheapest option for a flight between St. Louis to London Heathrow Airport.

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

As of April 2026, prices for St. Louis to London Heathrow Airport flights are approximately 26% more expensive 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	$538
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 $538. The best round-trip flight deal from St. Louis to London Heathrow Airport found on momondo in the last 72 hours is $896.

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

Frequently asked questions about flying from St. Louis to London Heathrow Airport

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 April 2026, there are 8 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 96.51% of the total bookings. Other popular models include Boeing 787-9 Dreamliner with 2.95%, Airbus A330-300 with 0.44%, and Embraer 175 with 0.11%.
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 37% of all bookings. The subsequent popular airlines are American Airlines at 23%, United Airlines at 17%, and Air Canada at 7%.

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
Delta	PriceFrom $483	Free Cancellation	Rating 7.9 8,400 reviews	Search Delta flights
KLM	PriceFrom $529	Free Cancellation	Rating 7.7 1,493 reviews	Search KLM flights
American Airlines	PriceFrom $563	Free Cancellation	Rating 7.1 11,564 reviews	Search American Airlines flights
Air Canada	PriceFrom $572	Free Cancellation	Rating 7.1 10,915 reviews	Search Air Canada flights
British Airways	PriceFrom $574	Free Cancellation	Rating 6.7 7,869 reviews	Search British Airways flights
Iberia	PriceFrom $577	Free Cancellation	Rating 7.0 3,176 reviews	Search Iberia flights
United Airlines	PriceFrom $580	Free Cancellation	Rating 7.4 9,561 reviews	Search United Airlines flights
Lufthansa	PriceFrom $635	Free Cancellation	Rating 6.8 7,905 reviews	Search Lufthansa flights

Gatwick

Hounslow

Milton Keynes

Luton

Dover

Hayes

Slough

Stratford-upon-Avon

Wembley

Crawley

Stansted

Croydon

Dartford

Brentwood

Cobham

Folkestone

Guildford

Romford

Harrow

Watford

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 $473

Flights to London City Airportfrom $674

Flights to London Stansted Airportfrom $522

Flights to London Luton Airportfrom $563

Flights to Glasgow Intl Airportfrom $566

Flights to Belfast Intl Airportfrom $711

Flights to London Southend Airportfrom $671

Flights to Belfast City Airportfrom $711

Cheap flights from St. Louis to London from $429

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 5/13. 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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Air Canada flights from St. Louis to London Heathrow Airport

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

United Airlines flights from St. Louis to London Heathrow Airport

Our best United Airlines 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 typical price of a round-trip flight between St. Louis and 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

Frequently asked questions about flying from St. Louis to London Heathrow Airport

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

Popular cities in the United Kingdom

Popular flights according to clicks in the last 7 days on momondo

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According to popular flight searches on momondo this year

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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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