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Cheap flights from St. Louis to London from $335

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 11/11. 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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0 bags

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Cheap round-trip flights

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Scandinavian Airlines Logo
11:39 am - 4:00 pmSTL-LHR
22h 21m2 stops
Scandinavian Airlines Logo
6:40 am - 9:58 pmLHR-STL
21h 18m2 stops
$601Scandinavian Airlines
Find Deal
Sat, Nov 15 - Sat, Nov 22
Scandinavian Airlines Logo
11:39 am - 5:40 pmSTL-LHR
24h 01m2 stops
Scandinavian Airlines Logo
7:05 am - 11:44 pmLHR-STL
22h 39m3 stops
$605Scandinavian Airlines
Find Deal
Thu, Nov 13 - Thu, Nov 20
Scandinavian Airlines Logo
11:39 am - 5:40 pmSTL-LHR
24h 01m2 stops
Scandinavian Airlines Logo
6:40 pm - 11:44 pmLHR-STL
35h 04m2 stops
$613Scandinavian Airlines
Find Deal
Thu, Nov 13 - Sun, Nov 16
United Airlines Logo
10:00 am - 7:10 amSTL-LHR
15h 10m2 stops
United Airlines Logo
6:35 am - 5:39 pmLHR-STL
17h 04m2 stops
$628United Airlines
Find Deal
Wed, Nov 12 - Wed, Nov 19
United Airlines Logo
10:00 am - 7:55 amSTL-LHR
15h 55m1 stop
United Airlines Logo
6:50 am - 3:47 pmLHR-STL
14h 57m2 stops
$629United Airlines
Find Deal
Tue, Nov 11 - Tue, Nov 18
Delta Logo
12:14 pm - 7:05 amSTL-LHR
12h 51m1 stop
Delta Logo
6:30 am - 8:47 pmLHR-STL
20h 17m2 stops
$630Delta
Find Deal
Mon, Nov 3 - Fri, Dec 12
Delta Logo
1:30 pm - 8:45 amSTL-LHR
14h 15m2 stops
Delta Logo
11:45 am - 8:46 pmLHR-STL
15h 01m2 stops
$635Delta
Find Deal
Wed, Oct 29 - Wed, Nov 12
Air Canada Logo
4:05 pm - 8:35 pmSTL-LHR
22h 30m2 stops
Air Canada Logo
1:25 pm - 12:15 pmLHR-STL
28h 50m2 stops
$638Air Canada
Find Deal
Sat, Nov 8 - Wed, Dec 10
Air Canada Logo
6:43 pm - 6:30 amSTL-LHR
29h 47m2 stops
Air Canada Logo
1:25 pm - 2:23 pmLHR-STL
30h 58m2 stops
$647Air Canada
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Mon, Nov 3 - Thu, Dec 11
Virgin Atlantic Logo
11:04 am - 7:50 amSTL-LHR
14h 46m1 stop
Virgin Atlantic Logo
8:55 am - 4:06 pmLHR-STL
13h 11m1 stop
$648Virgin Atlantic
Find Deal
Thu, Nov 27 - Thu, Dec 4

Scandinavian Airlines flights from St. Louis to London Heathrow Airport

Our best Scandinavian Airlines deals on St. Louis to London Heathrow Airport flight tickets
Scandinavian Airlines
Nov 15
STL11:39 amLambert-St Louis
22h 21m
2 stops
LHR4:00 pmLondon Heathrow
Nov 22
LHR6:40 amLondon Heathrow
21h 18m
2 stops
STL9:58 pmLambert-St Louis
$601
Find similar
Scandinavian Airlines
Nov 13
STL11:39 amLambert-St Louis
24h 01m
2 stops
LHR5:40 pmLondon Heathrow
Nov 20
LHR7:05 amLondon Heathrow
22h 39m
3 stops
STL11:44 pmLambert-St Louis
$605
Find similar
Scandinavian Airlines
Nov 13
STL11:39 amLambert-St Louis
24h 01m
2 stops
LHR5:40 pmLondon Heathrow
Nov 16
LHR6:40 pmLondon Heathrow
35h 04m
2 stops
STL11:44 pmLambert-St Louis
$613
Find similar

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
Oct 20
STL12:25 pmLambert-St Louis
13h 55m
1 stop
LHR8:20 amLondon Heathrow
Nov 5
LHR6:30 amLondon Heathrow
13h 25m
1 stop
STL1:55 pmLambert-St Louis
$627
Find similar
United Airlines
Nov 12
STL10:00 amLambert-St Louis
15h 10m
2 stops
LHR7:10 amLondon Heathrow
Nov 19
LHR6:35 amLondon Heathrow
17h 04m
2 stops
STL5:39 pmLambert-St Louis
$628
Find similar
United Airlines
Nov 11
STL10:00 amLambert-St Louis
15h 55m
1 stop
LHR7:55 amLondon Heathrow
Nov 18
LHR6:50 amLondon Heathrow
14h 57m
2 stops
STL3:47 pmLambert-St Louis
$629
Find similar

momondo Fare Finder

 
Customize your flight search to find flights from St. Louis to London Heathrow Airport 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, momondo users made 832,500 searches. Data last updated October 14, 2025.
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

Sat 11/15

11:39 am-4:00 pm

2 stops22h 21m

London Heathrow

Sat 11/22

6:40 am-9:58 pm

2 stops21h 18m

$601

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Thu 11/13

11:39 am-5:40 pm

2 stops24h 01m

London Heathrow

Thu 11/20

7:05 am-11:44 pm

3 stops22h 39m

$605

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Thu 11/13

11:39 am-5:40 pm

2 stops24h 01m

London Heathrow

Sun 11/16

6:40 pm-11:44 pm

2 stops35h 04m

$613

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 11/12

10:00 am-7:10 am

2 stops15h 10m

London Heathrow

Wed 11/19

6:35 am-5:39 pm

2 stops17h 04m

$628

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Tue 11/11

10:00 am-7:55 am

1 stop15h 55m

London Heathrow

Tue 11/18

6:50 am-3:47 pm

2 stops14h 57m

$629

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Mon 11/3

12:14 pm-7:05 am

1 stop12h 51m

London Heathrow

Fri 12/12

6:30 am-8:47 pm

2 stops20h 17m

$630

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 10/29

1:30 pm-8:45 am

2 stops14h 15m

London Heathrow

Wed 11/12

11:45 am-8:46 pm

2 stops15h 01m

$635

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Sat 11/8

4:05 pm-8:35 pm

2 stops22h 30m

London Heathrow

Wed 12/10

1:25 pm-12:15 pm

2 stops28h 50m

$638

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Mon 11/3

6:43 pm-6:30 am

2 stops29h 47m

London Heathrow

Thu 12/11

1:25 pm-2:23 pm

2 stops30h 58m

$647

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Thu 11/27

11:04 am-7:50 am

1 stop14h 46m

London Heathrow

Thu 12/4

8:55 am-4:06 pm

1 stop13h 11m

$648

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first
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See travel insights to London from

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

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 $727. If you’re not able to fly to London Heathrow Airport in October, then September is your next best option. Flight prices from St. Louis to London Heathrow Airport during September average around $767.

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

Our data shows that Tuesday is the least expensive day to fly to London Heathrow Airport. Tickets to fly out on this day can be as low as $597. The most expensive day to fly to London Heathrow Airport is Wednesday, with ticket prices averaging around $796.

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

According to our data, the cheapest time of day to fly to London Heathrow Airport is in the evening. momondo users have found flights departing from St. Louis to London Heathrow Airport in the evening for as low as $597. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. Flights in the morning are often more expensive with an average ticket price of $996.

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 $904 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 $743 on momondo.

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

There are 2 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.

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

$418

Direct flights

None
The best one-way flight to London Heathrow Airport from St. Louis in the past 72 hours is $418. The best round-trip flight deal from St. Louis to London Heathrow Airport found on momondo in the last 72 hours is $597.
There are no direct flights from St. Louis to London Heathrow Airport. There are no popular flight routes from St. Louis to London Heathrow Airport.
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 10h 25m.

  • 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?

  • 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?

  • What is the most popular airline 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
Airline
Rating
Free Cancellation
Price
KLMPriceFrom $529Free CancellationRating
7.7
1,402 reviews
Search KLM flights
Air CanadaPriceFrom $573Free CancellationRating
7.1
10,294 reviews
Search Air Canada flights
DeltaPriceFrom $580Free CancellationRating
7.9
7,972 reviews
Search Delta flights
United AirlinesPriceFrom $580Free CancellationRating
7.4
8,975 reviews
Search United Airlines flights
British AirwaysPriceFrom $580Free CancellationRating
6.7
7,454 reviews
Search British Airways flights
Scandinavian AirlinesPriceFrom $602Free CancellationRating
7.4
1,531 reviews
Search Scandinavian Airlines flights
American AirlinesPriceFrom $637Free CancellationRating
7.2
11,040 reviews
Search American Airlines flights
IberiaPriceFrom $654Free CancellationRating
7.0
2,988 reviews
Search Iberia flights
LufthansaPriceFrom $670Free CancellationRating
6.8
7,487 reviews
Search Lufthansa flights
Virgin AtlanticPriceFrom $736Free CancellationRating
7.4
667 reviews
Search Virgin Atlantic flights

Traveling to a place near London?

Book flights to London if you plan to visit one of these locations
Gatwick
Hounslow
Milton Keynes
Luton
Dover
Slough
Guildford
Dartford
Hayes
Crawley
Chelmsford
Brentwood
Salisbury
Colchester
Ilford
Folkestone
Romford
Swindon
Stratford-upon-Avon
Cobham

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.

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