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Cheap flights from London Heathrow Airport to St. Louis from £354

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from London Heathrow Airport to St. Louis departing on 20/9. 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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Find the cheapest flights from London Heathrow Airport to St. Louis

Cheap return flights

Enter your travel dates to find the best prices.
KLM Logo
11:45 - 23:37
LHR
-
STL
17h 52m
2 stops
KLM Logo
19:05 - 13:15
STL
-
LHR
12h 10m
1 stop
£632KLM
Wed, 2 Sep - Wed, 23 Sep
American Airlines Logo
16:25 - 19:30
LHR
-
STL
9h 05mdirect
American Airlines Logo
06:20 - 06:50
STL
-
LHR
18h 30m
1 stop
£632American Airlines
Wed, 9 Sep - Thu, 17 Sep
American Airlines Logo
14:45 - 23:59
LHR
-
STL
15h 14m
1 stop
American Airlines Logo
14:45 - 07:40
STL
-
LHR
10h 55m
1 stop
£637American Airlines
Mon, 7 Sep - Wed, 16 Sep
British Airways Logo
16:25 - 19:30
LHR
-
STL
9h 05mdirect
British Airways Logo
21:35 - 11:35
STL
-
LHR
8h 00mdirect
£641British Airways
Tue, 22 Sep - Tue, 6 Oct
British Airways Logo
16:25 - 19:30
LHR
-
STL
9h 05mdirect
British Airways Logo
12:52 - 06:55
STL
-
LHR
12h 03m
1 stop
£641British Airways
Tue, 22 Sep - Tue, 6 Oct
American Airlines Logo
16:25 - 19:30
LHR
-
STL
9h 05mdirect
American Airlines Logo
21:35 - 11:35
STL
-
LHR
8h 00mdirect
£643American Airlines
Tue, 22 Sep - Tue, 6 Oct
British Airways Logo
16:25 - 19:30
LHR
-
STL
9h 05mdirect
British Airways Logo
13:00 - 06:50
STL
-
LHR
11h 50m
1 stop
£644British Airways
Tue, 22 Sep - Tue, 6 Oct
American Airlines Logo
16:25 - 19:30
LHR
-
STL
9h 05mdirect
American Airlines Logo
14:47 - 06:50
STL
-
LHR
10h 03m
1 stop
£644American Airlines
Tue, 22 Sep - Tue, 6 Oct
British Airways Logo
12:30 - 18:58
LHR
-
STL
12h 28m
1 stop
British Airways Logo
18:51 - 12:50
STL
-
LHR
11h 59m
1 stop
£646British Airways
Tue, 22 Sep - Tue, 6 Oct
British Airways Logo
08:55 - 18:10
LHR
-
STL
15h 15m
1 stop
British Airways Logo
11:18 - 06:50
STL
-
LHR
13h 32m
1 stop
£647British Airways
Tue, 8 Sep - Tue, 22 Sep

American Airlines flights from London Heathrow Airport to St. Louis

Our best American Airlines deals on London Heathrow Airport to St. Louis flight tickets
American Airlines
9 Sept
LHR16:25London Heathrow
9h 05m
STL19:30Lambert-St Louis
15 Sept
STL17:46Lambert-St Louis
10h 34m
1 stop
LHR10:20London Heathrow
£632
American Airlines
7 Sept
LHR14:45London Heathrow
15h 14m
1 stop
STL23:59Lambert-St Louis
16 Sept
STL14:45Lambert-St Louis
10h 55m
1 stop
LHR07:40London Heathrow
£637
American Airlines
22 Sept
LHR16:25London Heathrow
9h 05m
STL19:30Lambert-St Louis
6 Oct
STL21:35Lambert-St Louis
8h 00m
LHR11:35London Heathrow
£643

British Airways flights from London Heathrow Airport to St. Louis

Our best British Airways deals on London Heathrow Airport to St. Louis flight tickets
British Airways
22 Sept
LHR16:25London Heathrow
9h 05m
STL19:30Lambert-St Louis
6 Oct
STL21:35Lambert-St Louis
8h 00m
LHR11:35London Heathrow
£641
British Airways
22 Sept
LHR16:25London Heathrow
9h 05m
STL19:30Lambert-St Louis
6 Oct
STL12:52Lambert-St Louis
12h 03m
1 stop
LHR06:55London Heathrow
£641
British Airways
22 Sept
LHR16:25London Heathrow
9h 05m
STL19:30Lambert-St Louis
6 Oct
STL13:00Lambert-St Louis
11h 50m
1 stop
LHR06:50London Heathrow
£644

momondo Fare Finder

 
Customise your flight search to find flights from London Heathrow Airport to St. Louis 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 279,928 searches. Data last updated 4 May 2026.
Use the filters below to find and compare flights from London Heathrow Airport to St. Louis that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Wed 2/9

11:45-23:37

2 stops17h 52m

Lambert-St Louis

Wed 23/9

19:05-13:15

1 stop12h 10m

£632

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Wed 9/9

16:25-19:30

Nonstop9h 05m

Lambert-St Louis

Thu 17/9

06:20-06:50

1 stop18h 30m

£632

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Mon 7/9

14:45-23:59

1 stop15h 14m

Lambert-St Louis

Wed 16/9

14:45-07:40

1 stop10h 55m

£637
Fastest return journey

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Tue 22/9

16:25-19:30

Nonstop9h 05m

Lambert-St Louis

Tue 6/10

21:35-11:35

Nonstop8h 00m

£641

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Tue 22/9

16:25-19:30

Nonstop9h 05m

Lambert-St Louis

Tue 6/10

12:52-06:55

1 stop12h 03m

£641

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Tue 22/9

16:25-19:30

Nonstop9h 05m

Lambert-St Louis

Tue 6/10

21:35-11:35

Nonstop8h 00m

£643

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Tue 22/9

16:25-19:30

Nonstop9h 05m

Lambert-St Louis

Tue 6/10

13:00-06:50

1 stop11h 50m

£644

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Tue 22/9

16:25-19:30

Nonstop9h 05m

Lambert-St Louis

Tue 6/10

14:47-06:50

1 stop10h 03m

£644

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Tue 22/9

12:30-18:58

1 stop12h 28m

Lambert-St Louis

Tue 6/10

18:51-12:50

1 stop11h 59m

£646

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Tue 8/9

08:55-18:10

1 stop15h 15m

Lambert-St Louis

Tue 22/9

11:18-06:50

1 stop13h 32m

£647

Flights are sorted by cheapest return flights first.

Showing 1-10 of 20 resultsSorted by cheapest first
1
2

See travel insights to St. Louis from

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

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 London Heathrow Airport and St. Louis?

What is the cheapest month to fly to St. Louis?

The month of February is, on average, the cheapest month to fly to St. Louis from London Heathrow Airport, with most prices found around £549. If you’re not able to fly to St. Louis in February, then March is your next best option. Flight prices from London Heathrow Airport to St. Louis during March average around £678.

What is the cheapest day to depart on your flight to St. Louis?

Our data shows that Saturday is the least expensive day to fly to St. Louis. Tickets to fly out on this day can be as low as £588. Flights from London Heathrow Airport to St. Louis on a Sunday will generally be more expensive and average around £754. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.

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

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

How far in advance should I book a flight from London Heathrow Airport to St. Louis?

You are more likely to see cheaper flights to St. Louis from London Heathrow Airport when booking weeks ahead of your departure date. In general, you can expect to find flights to St. Louis for around £730 when searching weeks before you fly. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to St. Louis from London Heathrow Airport for as low as £641 on momondo.

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

You could potentially save up to 26% on your flight if you consider stops on a London Heathrow Airport to St. Louis flight.

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

As of May 2026, prices for London Heathrow Airport to St. Louis flights are approximately 41% cheaper when compared to flights at the same time last year.

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

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

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

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

Best price found

£723

Fastest flight time

9h 05m

Direct flights

Mon, Wed, Thu and Sat

Airports in St. Louis

1 airport
The best flight deal from London Heathrow Airport to St. Louis found on momondo in the last 72 hours is £723
The fastest flight from London Heathrow Airport to St. Louis takes 9h 05m
Direct flights go from London Heathrow Airport to St. Louis on Monday, Wednesday, Thursday and Saturday. There are no airlines offering direct flights..
There is 1 airport in St. Louis. From London Heathrow Airport there are direct flights to Lambert-St Louis (STL).
Search flight deals

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

  • How far is London Heathrow to Lambert-St Louis by plane?

    The distance between London Heathrow and Lambert-St Louis is about 4185.8 mi. A reasonable flight in good conditions will take 9h 05m.

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

    Prices for flights from London Heathrow Airport to Lambert-St Louis Airport are refreshed on a daily basis.

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

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

    The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from London Heathrow Airport to Lambert-St Louis Airport.

  • What documentation or ID do you need to fly to Lambert-St Louis Airport?

    The travel and health documents required for your trip to Lambert-St Louis Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Lambert-St Louis Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

  • What is the most popular plane model from London Heathrow Airport to St. Louis?

  • What is the most popular airline from London Heathrow Airport to St. Louis?

Best airlines flying from London Heathrow Airport to St. Louis

Compare and see reviews for airlines that fly from London Heathrow Airport to St. Louis with momondo
Airline
Rating
Free Cancellation
Price
American AirlinesPriceFrom £197Free CancellationRating
7.1
11,670 reviews
Search American Airlines flights
Aer LingusPriceFrom £363Free CancellationRating
7.3
1,540 reviews
Search Aer Lingus flights
United AirlinesPriceFrom £467Free CancellationRating
7.4
9,680 reviews
Search United Airlines flights
British AirwaysPriceFrom £472Free CancellationRating
6.7
7,943 reviews
Search British Airways flights
KLMPriceFrom £513Free CancellationRating
7.8
1,511 reviews
Search KLM flights
Virgin AtlanticPriceFrom £548Free CancellationRating
7.4
688 reviews
Search Virgin Atlantic flights
FinnairPriceFrom £579Free CancellationRating
7.6
1,392 reviews
Search Finnair flights
Scandinavian AirlinesPriceFrom £588Free CancellationRating
7.4
1,769 reviews
Search Scandinavian Airlines flights
Air CanadaPriceFrom £595Free CancellationRating
7.1
10,995 reviews
Search Air Canada flights
LufthansaPriceFrom £644Free CancellationRating
6.8
7,972 reviews
Search Lufthansa flights

  • Finnair Flights From London Heathrow Airport to St. Louis

    The lowest priced Finnair flight from London Heathrow Airport to St. Louis from the last 72 hours was £579. Generally, Finnair has 4 flights on this route every week with an average price of £661. Finnair is rated 7.6/10 by our users.

  • Aer Lingus Flights From London Heathrow Airport to St. Louis

    £363 is the best Aer Lingus flight deal from London Heathrow Airport to St. Louis found on momondo over the last 72 hours. The average Aer Lingus ticket price found was closer to £718, however, with flight time and availability significantly affecting the price. Aer Lingus (7.3/10 from 1,540 user reviews) flies into St. Louis from London Heathrow Airport 4 times in an average week so prices can vary.

Travelling to a place near St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
Collinsville

Why use momondo?

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

We help find the flight that best suits your needs, momondo compares prices from hundreds of airlines and travel agents and helps you filter them to find the best flight from London to St. Louis for you.

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

momondo does allow users to show only those flights to St. Louis from London which offer a flexible booking policy as well as other useful filters and features.

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

momondo provides multiple filters to help you find the best flight to St. Louis from London. Filter by price, airline, airports, cabin, aircraft, payment method, number of stops and more.

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

Yes momondo offers price alerts on flights to St. Louis from London. 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 St. Louis trip

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