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Cheap flights from London Heathrow Airport to St. Louis from £356

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 20/9. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — STL
30 May — 6 Jun1
1 adult
1 adult, Economy, 0 bags
Cheapflights Tip: The best prices from London Heathrow to Lambert-St Louis are usually found in February or March, booked 72 days in advance, depart on a Thursday or Monday and return on a Wednesday

Cheap flight deals from Heathrow to St. Louis

Enter your travel dates to find the best prices.

Cheapest flights from Heathrow to St. Louis
Explore the most affordable flight options available from Heathrow to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 30 April 2026.

Tue 8/916:10
LHR
-
STL
2 stops37h 10m
Finnair
Tue 22/912:43
STL
-
LHR
1 stop14h 22m
Finnair
Deal found 27/4£630
Tue 15/914:45
LHR
-
STL
1 stop14h 35m
Finnair
Tue 22/912:43
STL
-
LHR
1 stop18h 07m
Finnair
Deal found 26/4£634
Wed 2/911:45
LHR
-
STL
2 stops17h 52m
KLM
Wed 23/919:05
STL
-
LHR
1 stop12h 10m
KLM
Deal found 29/4£636
Wed 11/1109:55
LHR
-
STL
1 stop13h 59m
American Airlines
Tue 24/1118:45
STL
-
LHR
1 stop10h 55m
American Airlines
Deal found 25/4£636
Mon 21/912:30
LHR
-
STL
1 stop12h 28m
American Airlines
Thu 5/1114:17
STL
-
LHR
1 stop10h 38m
American Airlines
Deal found 27/4£637
Wed 2/1213:10
LHR
-
STL
1 stop13h 11m
American Airlines
Tue 8/1209:30
STL
-
LHR
1 stop15h 20m
American Airlines
Deal found 27/4£638
Wed 2/907:50
LHR
-
STL
2 stops17h 09m
Multiple Airlines
Wed 23/917:11
STL
-
LHR
1 stop13h 39m
Multiple Airlines
Deal found 28/4£643
Tue 8/916:25
LHR
-
STL
Nonstop9h 05m
British Airways
Tue 22/912:47
STL
-
LHR
1 stop12h 08m
British Airways
Deal found 26/4£645
Tue 22/916:25
LHR
-
STL
Nonstop9h 05m
British Airways
Tue 6/1012:52
STL
-
LHR
1 stop12h 03m
British Airways
Deal found 28/4£647

Find flight deals from Heathrow to St. Louis

Discover tips and strategies to find the most affordable flight options for your journey from Heathrow (LHR) to St. Louis (STL). 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 30 April 2026.

Round-trip from

£630

One-way from

£356

Popular in

July

Cheapest in

February

Average price

£733

Good round-trip deal

£646 or less
Finnair
  • Finnair
  • 8/9-22/9
  • 3 total stops
  • 51h 32m total
  • London to St. Louis
Search Deals
British Airways
  • British Airways
  • 20/9
  • Nonstop
  • 9h 05m total
  • London to St. Louis
Search Deals
Highest demand for flights based on searches. 10% potential increase in price (£61 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease (£10 potential savings vs. average return price).
Search Deals
Average for round-trip flights in April 2026
Search Deals
Price to beat on a round-trip flight from London Heathrow to Lambert-St Louis.
Search Deals

Cheapflights Fare Finder

 
Customise your flight search to find flights from Heathrow 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, Cheapflights users made 858,174 searches. Data last updated 30 April 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 16/9

12:30-18:58

1 stop12h 28m

Lambert-St Louis

Mon 21/9

12:47-06:55

1 stop12h 08m

£651

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Wed 2/9

09:55-20:31

2 stops16h 36m

Lambert-St Louis

Wed 23/9

10:45-06:45

2 stops14h 00m

£653

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Wed 16/9

09:55-20:31

2 stops16h 36m

Lambert-St Louis

Wed 23/9

13:30-11:20

1 stop15h 50m

£653

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Mon 14/9

06:30-16:55

2 stops16h 25m

Lambert-St Louis

Sat 19/9

13:30-11:20

1 stop15h 50m

£685
Fastest return journey

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Wed 16/9

10:45-16:49

1 stop12h 04m

Lambert-St Louis

Fri 25/9

14:18-07:10

1 stop10h 52m

£698

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Thu 17/9

18:10-23:20

2 stops35h 10m

Lambert-St Louis

Wed 23/9

12:43-09:05

1 stop14h 22m

£728

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Sun 13/9

10:45-16:49

1 stop12h 04m

Lambert-St Louis

Fri 25/9

14:18-07:10

1 stop10h 52m

£728

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Sun 30/8

15:00-23:54

1 stop14h 54m

Lambert-St Louis

Fri 11/9

12:47-06:55

1 stop12h 08m

£768

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Wed 17/6

06:30-16:46

2 stops16h 16m

Lambert-St Louis

Tue 23/6

13:59-13:05

2 stops17h 06m

£775
Cheapest one-way
Fastest single journey

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Wed 9/9

16:25-19:30

Nonstop9h 05m

£416

Flights are sorted by cheapest return flights first.

Deals found on 27/4

Showing 1-10 of 16 resultsSorted by cheapest first
1
2

Best time to book a flight from Heathrow to St. Louis

Have a flexible travel schedule? Discover the best time to fly to St. Louis from Heathrow with our price prediction graph.
Estimated return 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 London Heathrow Airport to St. Louis

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

To ensure you get the cheapest price possible for a flight from London Heathrow Airport to St. Louis, you should look to book at least 71 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 London Heathrow Airport to St. Louis?

Currently, February is the cheapest month in which you can book a flight from London Heathrow Airport to St. Louis (average of £551). Flying from London Heathrow Airport to St. Louis in July is currently the most expensive (average of £865). 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.

What is the cheapest time of day to fly from LHR to STL?

Find hourly flight availability from Heathrow to St. Louis. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 30 April 2026.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from London Heathrow Airport to St. Louis as you normally would.

How much does it cost for a return flight from London Heathrow Airport to St. Louis?

Reviews of airlines servicing St. Louis

Get insights into the airlines that provide service to St. Louis. 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 St. Louis. Reviews last updated 30 April 2026.
Get a feel of what it's like to fly with United Airlines,Virgin Atlantic, andAir Canada from London Heathrow Airport to St. Louis 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
9,677 reviews
Check prices

Entertainment

7.1

Overall

7.4

Food

6.6

Comfort

7.3

Boarding

7.7

Crew

8.1

Reviews

1 / 20
8.0
Excellent

Anonymous,Apr 2026

DFW - EWR

The flight was on time. Crew was friendly. Will fly again. The seats was comfortable.
United Airlines
7.4
Good
9,677 reviews
United Airlines
7.4
Good
9,677 reviews
Check prices

Entertainment

7.1

Overall

7.4

Food

6.6

Comfort

7.3

Boarding

7.7

Crew

8.1

Reviews

1 / 20
8.0
Excellent

Anonymous,Apr 2026

DFW - EWR

The flight was on time. Crew was friendly. Will fly again. The seats was comfortable.
Virgin Atlantic
7.4
Good
688 reviews
United Airlines
7.4
Good
9,677 reviews
Check prices

Entertainment

7.1

Overall

7.4

Food

6.6

Comfort

7.3

Boarding

7.7

Crew

8.1

Reviews

1 / 20
8.0
Excellent

Anonymous,Apr 2026

DFW - EWR

The flight was on time. Crew was friendly. Will fly again. The seats was comfortable.
Air Canada
7.1
Good
10,982 reviews
United Airlines
7.4
Good
9,677 reviews
Check prices

Entertainment

7.1

Overall

7.4

Food

6.6

Comfort

7.3

Boarding

7.7

Crew

8.1

Reviews

1 / 20
8.0
Excellent

Anonymous,Apr 2026

DFW - EWR

The flight was on time. Crew was friendly. Will fly again. The seats was comfortable.
Lufthansa
6.8
Okay
7,962 reviews
United Airlines
7.4
Good
9,677 reviews
Check prices

Entertainment

7.1

Overall

7.4

Food

6.6

Comfort

7.3

Boarding

7.7

Crew

8.1

Reviews

1 / 20
8.0
Excellent

Anonymous,Apr 2026

DFW - EWR

The flight was on time. Crew was friendly. Will fly again. The seats was comfortable.
British Airways
6.7
Okay
7,937 reviews
United Airlines
7.4
Good
9,677 reviews
Check prices

Entertainment

7.1

Overall

7.4

Food

6.6

Comfort

7.3

Boarding

7.7

Crew

8.1

Reviews

1 / 20
8.0
Excellent

Anonymous,Apr 2026

DFW - EWR

The flight was on time. Crew was friendly. Will fly again. The seats was comfortable.

Related info for your journey

Find useful and relevant information for your journey from Heathrow to St. Louis. 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 into for flights to St. Louis from London Heathrow?

    For a flight from London Heathrow to St. Louis, you will be flying into Lambert-St Louis. Lambert-St Louis (STL) is just 12.7 mi from the center of the city. Lambert-St Louis is the only St. Louis airport and it handles 2 inbound flights from London Heathrow per day. 10 airlines have flights to Lambert-St Louis from London Heathrow on a regular basis.

  • How long is the flight from London Heathrow Airport to St. Louis?

    Departing from London Heathrow Airport to St. Louis will take you 12h 28m. London Heathrow Airport and St. Louis are separated by a distance of 4186 mi. This flight may include one or multiple stops.

  • What are the cheapest airlines flying from London Heathrow Airport to St. Louis round-trip?

    Cheapflights users have booked flights from London Heathrow Airport to St. Louis round-trip from £172. Other airlines that can offer you cheap pricing are United Airlines, from £470, and British Airways, from £475. American Airlines is priced at 76% lower than the current average price of a flight leaving 3 months from now.

  • What are the cheapest airlines to fly from London Heathrow Airport to St. Louis one-way?

    For one-way options, check prices for British Airways. According to our data, you can fly for as low as £340. Users have also found prices from £356 and £359 on United Airlines and Finnair, respectively.

  • What are the cheapest flights from London Heathrow Airport to St. Louis?

    While on average a flight from London Heathrow Airport to St. Louis is generally £1,298, our data shows the cheapest flight currently is £604. When looking at the most popular route, (London Heathrow - Lambert-St Louis), you can expect to pay £628 for that flight.

  • Can I find deals for flights from Heathrow to St. Louis that include hotel bookings?

    Yes. In addition to deals on Heathrow to St. Louis flights, Cheapflights offers holiday packages that include both flights and hotel.

  • How can I find direct flights from Heathrow to St. Louis?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Heathrow to St. Louis.

  • Can I find deals for business class flights from Heathrow to St. Louis?

    Yes. Cheapflights offers flight deals from Heathrow to St. Louis 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 London Heathrow Airport to St. Louis?

    Currently, February is the cheapest month in which you can book a flight from London Heathrow Airport to St. Louis (average of £551). Flying from London Heathrow Airport to St. Louis in July is currently the most expensive (average of £865). 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

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 Heathrow to St. Louis

Discover the top 10 airlines that operate flights from Heathrow to St. Louis. 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 858,174 searches. Data last updated 30 April 2026.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest£172Average£714FlexibilityNo cancel feeOn-time71%
Search American Airlines flights
United AirlinesCheapest£470Average£732FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
British AirwaysCheapest£475Average£732FlexibilityNo cancel feeOn-time70%
Search British Airways flights
KLMCheapest£516Average£746FlexibilityNo cancel feeOn-time75%
Search KLM flights
Virgin AtlanticCheapest£551Average£768FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
FinnairCheapest£582Average£665FlexibilityNo cancel feeOn-time76%
Search Finnair flights
Scandinavian AirlinesCheapest£592Average£699FlexibilityNo cancel feeOn-time77%
Search Scandinavian Airlines flights
Air CanadaCheapest£599Average£713FlexibilityNo cancel feeOn-time67%
Search Air Canada flights
LufthansaCheapest£648Average£796FlexibilityNo cancel feeOn-time76%
Search Lufthansa flights
IberiaCheapest£652Average£716FlexibilityNo cancel feeOn-time77%
Search Iberia flights

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travellers can enjoy low prices and a wide availability of flights to their desired destinations.

How does Cheapflights help users find flights from Heathrow to St. Louis?

Cheapflights makes it easy to find Heathrow to St. Louis flights by helping our users search from 900+ travel sites for deals. We also provide you with filters for cabin, price, airline, airports, number of stops, and many more to narrow down that perfect flight.

Why should you use Cheapflights to find cheap flight tickets from Heathrow to St. Louis?

By finding flights from multiple airlines and providers at completely no cost, Cheapflights helps millions of users like you annually find the best flights to St. Louis from Heathrow.

Can Cheapflights find flights from Heathrow to St. Louis with no change fees?

Certainly. Search results for flights to St. Louis from Heathrow shown to you on Cheapflights can be narrowed down with different useful search filters, which includes flexible booking options.

Can Cheapflights notify me if prices for flights from Heathrow to St. Louis become cheaper?

Yes, Cheapflights offers price alerts on Heathrow to St. Louis flights so you can book your travel at the perfect time. Price Alerts can be enabled by clicking the bell icon next to the flight deals above and providing your email address where you want to receive the alerts.

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