Latest deals
Insights
When to book
FAQs
Reviews
Price Alerts

Cheap flights from St. Louis to London from $347

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 3/21. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
1 adult
0 bags

Deals available from 900+ travel sites.

Save money when you book flights with momondo
Big names and deals
Big names and deals
Search 100s of travel sites to compare prices.
Filter for what you want
Filter for what you want
Free Wi-Fi? Stopover? Instantly customize your results.
Trusted and free
Trusted and free
We’re completely free to use - no hidden charges or fees.
Price Alerts
Price Alerts
Not ready to book? to track prices.

Find the cheapest flights from St. Louis to London

Cheap round-trip flights

These are some of the best round-trip flight deals from St. Louis to London that have been recently found on momondo from popular airlines, departing in the coming months.
4:57 pm - 10:00 amSTL-LGW
35h 03m1 stop
2:00 pm - 12:04 amLGW-STL
16h 04m1 stop
Wed, Apr 9 - Tue, Apr 22
3:50 pm - 6:30 amSTL-LHR
32h 40m2 stops
2:05 pm - 2:49 pmLHR-STL
30h 44m2 stops
$645Air Canada
Find Deal
Mon, Mar 31 - Wed, Apr 16
3:29 pm - 7:25 amSTL-LHR
9h 56m1 stop
12:15 pm - 10:12 pmLHR-STL
15h 57m1 stop
$674Iberia
Find Deal
Tue, Apr 15 - Tue, Apr 22
10:55 am - 7:30 amSTL-LHR
15h 35m1 stop
3:00 pm - 2:23 pmLHR-STL
28h 23m2 stops
$677United Airlines
Find Deal
Wed, Mar 19 - Wed, Mar 26
9:39 am - 10:00 amSTL-LHR
18h 21m2 stops
6:30 am - 1:30 pmLHR-STL
13h 00m1 stop
$678United Airlines
Find Deal
Tue, Apr 22 - Wed, Apr 30
3:29 pm - 12:15 pmSTL-LHR
14h 46m1 stop
6:10 am - 6:02 pmLHR-STL
17h 52m2 stops
$682British Airways
Find Deal
Mon, Apr 7 - Tue, Apr 15
6:00 pm - 10:00 amSTL-LHR
10h 00m1 stop
8:00 pm - 10:12 pmLHR-STL
32h 12m2 stops
$691British Airways
Find Deal
Tue, Mar 4 - Wed, Apr 9
2:21 pm - 7:50 amSTL-LHR
11h 29m1 stop
10:15 am - 8:41 pmLHR-STL
15h 26m1 stop
$700American Airlines
Find Deal
Wed, Mar 5 - Wed, Mar 12
6:00 pm - 12:15 pmSTL-LHR
12h 15m1 stop
12:00 pm - 10:28 pmLHR-STL
16h 28m1 stop
$765Iberia
Find Deal
Thu, Apr 10 - Thu, Apr 17
1:51 pm - 7:00 amSTL-LHR
12h 09m1 stop
1:30 pm - 8:41 pmLHR-STL
13h 11m1 stop
$938American Airlines
Find Deal
Wed, Mar 26 - Sun, Mar 30

Air Canada flights from St. Louis to London

Our best Air Canada deals on St. Louis to London flight tickets
Air Canada
Mar 31
STL3:50 pmLambert-St Louis
32h 40m
2 stops
LHR6:30 amLondon Heathrow
Apr 16
LHR2:05 pmLondon Heathrow
30h 44m
2 stops
STL2:49 pmLambert-St Louis
Air Canada
Mar 31
STL3:50 pmLambert-St Louis
32h 40m
2 stops
LHR6:30 amLondon Heathrow
Apr 16
LHR8:30 amLondon Heathrow
12h 19m
1 stop
STL2:49 pmLambert-St Louis
Air Canada
Mar 31
STL3:50 pmLambert-St Louis
32h 40m
2 stops
LHR6:30 amLondon Heathrow
Apr 16
LHR2:05 pmLondon Heathrow
30h 44m
2 stops
STL2:49 pmLambert-St Louis

Iberia flights from St. Louis to London

Our best Iberia deals on St. Louis to London flight tickets
Iberia
Apr 15
STL3:29 pmLambert-St Louis
9h 56m
1 stop
LHR7:25 amLondon Heathrow
Apr 22
LHR12:15 pmLondon Heathrow
15h 57m
1 stop
STL10:12 pmLambert-St Louis
Iberia
Mar 5
STL9:25 amLambert-St Louis
16h 25m
1 stop
LHR7:50 amLondon Heathrow
Mar 10
LHR1:50 pmLondon Heathrow
13h 28m
1 stop
STL10:18 pmLambert-St Louis
Iberia
Apr 10
STL6:00 pmLambert-St Louis
12h 15m
1 stop
LHR12:15 pmLondon Heathrow
Apr 17
LHR12:00 pmLondon Heathrow
16h 28m
1 stop
STL10:28 pmLambert-St Louis

See travel insights to London from

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

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 cheapest month to fly to London?

The cheapest month to fly to London from St. Louis is in April. Flight prices, which tend to average around $756, are often lower during this time because this is during the off-season. The month of November is another great option to travel to London, with average flight prices from St. Louis averaging around $786.

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

The cheapest day to depart from St. Louis to London is on a Wednesday. Travelers who choose to depart for London on a Wednesday will often find tickets for as low as $846. If your travel schedule is flexible, try to avoid departing on a Tuesday because tickets tend to average around $1,006. These prices are subject to change though, so be sure to set up a Price Alert for flights to London.

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

Flying to London from St. Louis in the morning is the least expensive time of day to depart. momondo users have found prices as low as $915 when looking at flights departing in the morning. Flights to London are more costly at noon, with an average ticket price of $958. Departure times at noon fall within the peak daily travel times, which is why tickets can be more expensive.

How far in advance should I book a flight to London?

You are more likely to see cheaper flights to London from St. Louis when booking 9 weeks ahead of your departure date. In general, you can expect to find flights to London for around $950 when searching 9 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to London from St. Louis for as low as $795 on momondo.

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

As of February 2025, prices for St. Louis to London flights are approximately 25% cheaper when compared to flights at the same time last year.

When to book flights from St. Louis to London

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

Cheap St. Louis to London (STL to LON) flight deals and tips

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

Best Price Found

$347

Fastest flight time

9h 56m

Direct flights

None

Airports in London

5 airports
The best one-way flight to London from St. Louis in the past 72 hours is $347. The best round-trip flight deal from St. Louis to London found on momondo in the last 72 hours is $607.
The fastest flight from St. Louis to London takes 9h 56m
There are no direct flights from St. Louis to London. Popular non-direct routes for this connection are Lambert-St Louis Airport - London Gatwick Airport, Lambert-St Louis Airport - London Stansted Airport and Lambert-St Louis Airport - London Heathrow Airport.
There are 5 airports near London: London City (LCY), London Heathrow (LHR), London Luton (LTN), London Stansted (STN), London Gatwick (LGW)

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

    London is 4197.7 mi away from Lambert-St Louis. Flights usually cover this in 9h 56m, depending on flying conditions and air traffic around both airports.

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

    Prices for flights from Lambert-St Louis Airport to London were last updated today.

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

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

    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.

  • What documentation or ID do you need to fly to London?

    The travel and health documents you'll need for your trip to London may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at London. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

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


Best airlines flying from St. Louis to London

Compare and see reviews for airlines that fly from St. Louis to London with momondo
Airline
Rating
Free Cancellation
Price
KLMPriceFrom $490Free CancellationRating
7.8
1,333 reviews
Search KLM flights
IberiaPriceFrom $631Free CancellationRating
7.0
2,639 reviews
Search Iberia flights
American AirlinesPriceFrom $651Free CancellationRating
7.2
10,000 reviews
Search American Airlines flights
Virgin AtlanticPriceFrom $654Free CancellationRating
7.5
654 reviews
Search Virgin Atlantic flights
United AirlinesPriceFrom $675Free CancellationRating
7.4
8,765 reviews
Search United Airlines flights
British AirwaysPriceFrom $685Free CancellationRating
6.6
6,762 reviews
Search British Airways flights
DeltaPriceFrom $713Free CancellationRating
8.0
8,219 reviews
Search Delta flights
Air CanadaPriceFrom $728Free CancellationRating
7.0
8,748 reviews
Search Air Canada flights
LufthansaPriceFrom $734Free CancellationRating
6.7
6,986 reviews
Search Lufthansa flights

Traveling to a place near London?

Book flights to London if you plan to visit one of these locations
Hounslow
Gatwick
Croydon
Luton
Slough
Guildford
Ipswich
Hayes
Stansted
Ilford
Canterbury
Dover
Milton Keynes
Dartford
Horley
Colchester
Wembley
Eastbourne
Chelmsford
St. Albans

Why use momondo?

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

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 St. Louis to London for you.

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

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

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

Once you have performed a search for St. Louis to London flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.

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

If you are not ready to book a flight from St. Louis to London now, use our insights above to find helpful tips or alternatively set up a price alert, where momondo will track prices on flights to London and let you know when they change.


An easier way to manage your London 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.
1 adult
From?
To?
Tue 2/25
Tue 3/4

Find better results for your trip to the United Kingdom

Fly into one of these airports located in London

Airports listed have a maximum distance of 35.6 mi from London