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Cheap flights from St. Louis to London Heathrow Airport from £319

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 8/4. Fares are subject to change and may not be available on all flights or dates of travel.
STL — LHR
30 Mar — 6 Apr1
1 adult

Cheapflights Tip: The best prices from Lambert-St Louis to London Heathrow are usually found in October or September, booked 56 days in advance, depart on a Tuesday or Wednesday and return on a Wednesday

Cheap flight deals from St. Louis to Heathrow

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Heathrow (LHR). 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 25 March 2025.

Round-trip from

£531

One-way from

£319

Popular in

June

Cheapest in

October

Average price

£640
Iberia
  • Iberia
  • 28/4-7/5
  • 2 total stops
  • 22h 48m total
  • St. Louis to London
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8/4
  • 8/4
  • 3 total stops
  • 17h 40m total
  • St. Louis to London
Search Deals
Highest demand for flights based on searches. 15% potential increase in price (£101 potential increase over avg. return price).
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Cheapest flight prices on average. 2% potential price decrease (£15 potential savings vs. average return price).
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Average for round-trip flights in March 2025
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Find flight deals from St. Louis to Heathrow

Cheapest flights from St. Louis to Heathrow
Explore the most affordable flight options available from St. Louis to Heathrow. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 25 March 2025.

Mon 28/418:00STL - LHR
1 stop10h 30mIberia
Wed 7/512:15LHR - STL
1 stop12h 18mIberia
Deal found 24/3£531
Thu 8/513:30STL - LHR
1 stop14h 30mMultiple Airlines
Thu 15/510:30LHR - STL
2 stops15h 28mMultiple Airlines
Deal found 24/3£532
Tue 13/513:38STL - LHR
1 stop16h 37mBritish Airways
Tue 20/517:20LHR - STL
2 stops31h 13mBritish Airways
Deal found 24/3£534
Sat 11/1016:30STL - LHR
1 stop35h 10mUnited Airlines
Tue 21/1017:40LHR - STL
1 stop31h 53mUnited Airlines
Deal found 24/3£535
Tue 13/511:32STL - LHR
1 stop19h 38mDelta
Thu 5/606:15LHR - STL
2 stops16h 45mDelta
Deal found 24/3£537
Thu 15/507:30STL - LHR
1 stop17h 05mAir Canada
Thu 22/508:40LHR - STL
2 stops17h 18mAir Canada
Deal found 24/3£544
Sat 12/417:33STL - LHR
2 stops18h 07mLufthansa
Wed 23/406:30LHR - STL
1 stop13h 00mLufthansa
Deal found 24/3£565
Mon 1/914:18STL - LHR
2 stops14h 12mVirgin Atlantic
Sun 7/911:45LHR - STL
2 stops17h 54mVirgin Atlantic
Deal found 24/3£588
Wed 26/313:06STL - LHR
2 stops23h 34mScandinavian Airlines
Wed 2/417:00LHR - STL
2 stops36h 29mScandinavian Airlines
Deal found 24/3£615
Wed 23/411:06STL - LHR
1 stop21h 19mFinnair
Wed 30/410:20LHR - STL
2 stops17h 52mFinnair
Deal found 25/3£664
Wed 2/411:55STL - LHR
2 stops16h 25mAer Lingus
Wed 23/413:25LHR - STL
2 stops16h 08mAer Lingus
Deal found 24/3£665

Cheapflights Fare Finder

Customise your flight search to find flights from St. Louis to Heathrow 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 25 March 2025.
Use the filters below to find and compare flights from St. Louis to London Heathrow Airport that are best for you.

Fly from

St. Louis

Fly to

Heathrow

Route

Depart

Return

Price

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Mon 28/4

18:00-10:30

1 stop10h 30m

London Heathrow

Wed 7/5

12:15-18:33

1 stop12h 18m

£531

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Thu 8/5

13:30-10:00

1 stop14h 30m

London Heathrow

Thu 15/5

10:30-19:58

2 stops15h 28m

£532

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Tue 13/5

13:38-12:15

1 stop16h 37m

London Heathrow

Tue 20/5

17:20-18:33

2 stops31h 13m

£534

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 7/5

10:05-11:10

1 stop19h 05m

London Heathrow

Wed 21/5

09:55-20:39

2 stops16h 44m

£535

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Mon 28/4

09:39-06:55

2 stops15h 16m

London Heathrow

Wed 7/5

08:40-19:35

2 stops16h 55m

£537

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Thu 15/5

07:30-06:35

1 stop17h 05m

London Heathrow

Thu 22/5

08:40-19:58

2 stops17h 18m

£544

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Sat 12/4

17:33-17:40

2 stops18h 07m

London Heathrow

Wed 23/4

06:30-13:30

1 stop13h 00m

£565

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Mon 1/9

14:18-10:30

2 stops14h 12m

London Heathrow

Sun 7/9

11:45-23:39

2 stops17h 54m

£588

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Mon 5/5

16:05-21:40

2 stops23h 35m

London Heathrow

Thu 15/5

21:05-20:39

3 stops29h 34m

£630

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 23/4

11:06-14:25

1 stop21h 19m

London Heathrow

Wed 30/4

10:20-22:12

2 stops17h 52m

£664

Flights are sorted by cheapest return flights first.

Deals found on 25/3

Showing 1-10 of 22 results
1
2
3

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

Have a flexible travel schedule? Discover the best time to fly to Heathrow from St. Louis 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 St. Louis to London Heathrow Airport

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

Use this chart to determine the optimal time to book a return flight from St. Louis to Heathrow. Price data was last updated on 21 March 2025.

The best time to book flights from St. Louis to London Heathrow Airport is 56 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

What is the cheapest month to book a flight from St. Louis to London Heathrow Airport?

Currently, January is the cheapest month in which you can book a flight from St. Louis to London Heathrow Airport (average of £112). Flying from St. Louis to London Heathrow Airport in August is currently the most expensive (average of £164). 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 STL to LHR?

Find hourly flight availability from St. Louis to Heathrow. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 25 March 2025.

Unlike in the afternoon, when flights are generally more expensive, you can save up to 20% on flights from St. Louis to London Heathrow Airport by exploring options for tickets in the morning.

Rainfall in Heathrow by month

Plan your trip to Heathrow by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in London Heathrow Airport ranges from 40.0 - 70.0 inches per month. January is typically the wettest month, when rainfall can reach 70.0 mm. July is typically the driest time to visit London Heathrow Airport when rainfall is around 40.0 mm.

Temperature in Heathrow by month

Plan your trip to Heathrow by taking into account the average temperature totals by month.

If weather is an important factor for your trip to London Heathrow Airport, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 17.0 C. Travellers hoping to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 4.0 C).

Reviews of airlines servicing Heathrow

Get insights into the airlines that provide service to Heathrow. 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 Heathrow. Reviews last updated 25 March 2025.
Read reviews from past customers who have flown Delta, KLM and Finnair from St. Louis to London. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very Good
7,890 reviews
Check prices

Boarding

8.2

Comfort

8.0

Entertainment

7.9

Food

7.3

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
Delta
8.0
Very Good
7,890 reviews
Delta
8.0
Very Good
7,890 reviews
Check prices

Boarding

8.2

Comfort

8.0

Entertainment

7.9

Food

7.3

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
KLM
7.8
Good
1,318 reviews
Delta
8.0
Very Good
7,890 reviews
Check prices

Boarding

8.2

Comfort

8.0

Entertainment

7.9

Food

7.3

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
Finnair
7.6
Good
1,266 reviews
Delta
8.0
Very Good
7,890 reviews
Check prices

Boarding

8.2

Comfort

8.0

Entertainment

7.9

Food

7.3

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
United Airlines
7.4
Good
8,605 reviews
Delta
8.0
Very Good
7,890 reviews
Check prices

Boarding

8.2

Comfort

8.0

Entertainment

7.9

Food

7.3

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
Virgin Atlantic
7.4
Good
634 reviews
Delta
8.0
Very Good
7,890 reviews
Check prices

Boarding

8.2

Comfort

8.0

Entertainment

7.9

Food

7.3

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

Related info for your journey

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

    Lambert-St Louis (STL) is the airport you will fly out of if you book a flight from St. Louis to London Heathrow. You should not have trouble finding flights to London Heathrow from Lambert-St Louis; the airport handles an average of 0 outbound flights to London Heathrow per day. You should also have plenty of airline options to choose from since 4 airlines have flights from the St. Louis airport to London Heathrow. It is only a 12.7 mi journey to Lambert-St Louis (STL) from St. Louis’s city center.

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

    Iberia, at £531, was found to be the cheapest airline from St. Louis to London Heathrow Airport.Alternate airlines flying return to your destination include British Airways and Delta. You may be able to fly from St. Louis to London Heathrow Airport for 27% less than the average price by searching for these airlines.

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

    The cheapest airline one-way is Aer Lingus, with whom users have recently found tickets for as low as £343. However, be on the lookout for offers from KLM and Iberia, as they are both options that can get you from St. Louis to London Heathrow Airport for a low price.

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

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

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

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

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

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

    Currently, January is the cheapest month in which you can book a flight from St. Louis to London Heathrow Airport (average of £112). Flying from St. Louis to London Heathrow Airport in August is currently the most expensive (average of £164). 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

Travelling to a place near St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
Hounslow
Deal
Milton Keynes
Gatwick
Croydon
Luton
Slough
Eastbourne
Wembley
Northampton
Swindon
Hayes
Ilford
Crawley
Southend-on-Sea
Winchester
Maidstone
Ipswich
Watford
Southall

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Top 4 airlines flying from St. Louis to Heathrow

Discover the top 4 airlines that operate flights from St. Louis to Heathrow. 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 25 March 2025.
AirlineCheapestAverageFlexibilityOn-time
British AirwaysCheapest£509Average£867FlexibilityNo cancel feeOn-time70%
Search British Airways flights
Virgin AtlanticCheapest£544Average£856FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
KLMCheapest£550Average£829FlexibilityNo cancel feeOn-time75%
Search KLM flights
American AirlinesCheapest£607Average£1,201FlexibilityNo cancel feeOn-time71%
Search American Airlines flights

Fly with Cheapflights

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

Cheapflights helps you search for flights from St. Louis to Heathrow via 900+ travel sites so you don’t have to. After performing a flight search, users can also filter their flight selection by filtering for price, number of stops, airlines, and so on.

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

It’s simple! Cheapflights, which is free to use for everyone, saves millions of users time and money every year by helping them find the cheapest and most suitable flights from St. Louis to Heathrow.

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

Yes! Cheapflights helps users easily find flights from St. Louis to Heathrow with no change fees.

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

Not ready to book yet? You can track prices for flights from St. Louis to Heathrow on Cheapflights with our Price Alert feature and get notified when better prices are available.

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