STL - LHR

$320 Find Cheap Flights from St. Louis to London Heathrow Airport - Compare and Save

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from St. Louis to Heathrow departing on 9/16. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to London Heathrow Airport

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from St. Louis to London.
These are the airlines KAYAK users have selected most often from within our search results in flight searches from St. Louis to London.
Travelers love KAYAK
41,299,237 searches in the past 7 days on KAYAK

Save 21% or moreCompare multiple travel sites with one search.

Track pricesNot ready to book? Create a price alert for when prices drop.

Bundle and saveSave money when you bundle your flight + hotel.

Filter your dealsChoose cabin class, free Wi-Fi and more.

Everything you should know

Cheapest round-trip
$1,071
Typical prices: $948-$658
Lufthansa
Sat 9/5Sun 9/13
STL - LHR • 2 stops
Cheapest non-stop
$1,079
British Airways
Wed 8/26Wed 9/2
STL - LHR • Non-stop
Nonstop flights
Tue, Wed, Fri, Sun
You can fly direct with British Airways. Average duration is 8h 00m
Direct flights
Direct flights
+1
+1
Direct flights
Direct flights
+1
Top airlines
Cheapest • from $1,071 (round-trip)
Best reviews • 7.4 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
Top layover airports
Cheapest • Avg $728 (round-trip)
Shortest trip • 10h 52m (one-way)
Insights
Insights
Insights
Insights
Avoid delays
Most punctual • 73% on-time
Best time • Fewest delays
Insights
Insights
Insights
Insights
When to travel
Cheapest • 26% price drop
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
Start a new search
KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to Heathrow!
Flight Deals
Booking Insights
Flight Deals

Cheap Flights from St. Louis to Heathrow (STL-LHR)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from St. Louis to Heathrow that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from St. Louis to Heathrow

Sat, Sep 5 - Sun, Sep 13
Lufthansa Logo
6:54 pm - 4:40 pm
STL
-
LHR
15h 46m
2 stops
Lufthansa Logo
6:30 am - 9:36 pm
LHR
-
STL
21h 06m
2 stops
$1,071Lufthansa
Fri, Sep 4 - Sat, Sep 12
Multiple Airlines Logo
8:55 am - 6:30 am
STL
-
LHR
15h 35m
2 stops
Multiple Airlines Logo
12:40 pm - 9:30 pm
LHR
-
STL
14h 50m
2 stops
$1,072Multiple Airlines
Fri, Sep 4 - Sun, Sep 13
Air Canada Logo
2:40 pm - 10:00 am
STL
-
LHR
13h 20m
2 stops
Air Canada Logo
8:30 am - 6:41 pm
LHR
-
STL
16h 11m
2 stops
$1,073Air Canada
Fri, Aug 28 - Tue, Sep 1
Air Canada Logo
12:10 pm - 6:30 am
STL
-
LHR
12h 20m
1 stop
Air Canada Logo
9:30 am - 6:42 pm
LHR
-
STL
15h 12m
1 stop
$1,074Air Canada
Fri, Oct 9 - Sun, Oct 18
British Airways Logo
9:35 pm - 11:35 am
STL
-
LHR
8h 00mnonstop
British Airways Logo
1:10 pm - 8:08 pm
LHR
-
STL
12h 58m
1 stop
$1,075British Airways
Fri, Nov 27 - Wed, Dec 2
Air Canada Logo
4:15 pm - 8:30 am
STL
-
LHR
10h 15m
1 stop
Air Canada Logo
1:00 pm - 10:54 pm
LHR
-
STL
15h 54m
2 stops
$1,076Air Canada
Fri, Jul 31 - Wed, Aug 12
Lufthansa Logo
1:13 pm - 2:40 pm
STL
-
LHR
19h 27m
2 stops
Lufthansa Logo
11:30 am - 10:59 pm
LHR
-
STL
17h 29m
2 stops
$1,077Lufthansa
Wed, Aug 26 - Wed, Sep 2
British Airways Logo
9:35 pm - 11:35 am
STL
-
LHR
8h 00mnonstop
British Airways Logo
4:25 pm - 7:30 pm
LHR
-
STL
9h 05mnonstop
$1,079British Airways
Wed, Aug 26 - Wed, Sep 2
British Airways Logo
9:35 pm - 11:35 am
STL
-
LHR
8h 00mnonstop
British Airways Logo
4:25 pm - 7:30 pm
LHR
-
STL
9h 05mnonstop
$1,080British Airways
Fri, Sep 18 - Mon, Sep 28
British Airways Logo
9:35 pm - 11:35 am
STL
-
LHR
8h 00mnonstop
British Airways Logo
9:45 am - 4:48 pm
LHR
-
STL
13h 03m
1 stop
$1,081British Airways
Booking Insights

KAYAK's insights & trends for St. Louis to Heathrow flights

Get data-powered insights and trends into flights from St. Louis to Heathrow to help you find the cheapest flights, the best time to fly and much more.

How much is a round-trip flight from St. Louis to London Heathrow Airport?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from St. Louis to London Heathrow Airport departing in September.

What is the cheapest month to fly from St. Louis to London Heathrow Airport?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from St. Louis to London Heathrow Airport, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from St. Louis to London Heathrow Airport is October, where tickets cost $652 (return) on average. On the other hand, the most expensive months are June and July, where the average cost of round-trip tickets is $1,445 and $1,098 respectively.

Can I save money by flying with a layover from St. Louis to London Heathrow Airport?

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.

Yes, flying with a layover may cost you more time, but you can also save money on the route, with a 1 stop layover the cheapest option at $1,325 on average.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from St. Louis to London Heathrow Airport, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from St. Louis to London Heathrow Airport, you should book around 1 week before departure. For the absolute cheapest price, our data suggests you should book 8 weeks before departure.

Good to know

Low seasonJanuary
Cheapest flight$320
Best time to beat the crowds but there is an average 3% increase in price.
Most popular time to fly with an average 16% increase in price.
Flight from St. Louis to London Heathrow Airport

When to book flights from St. Louis to Heathrow

Are your dates flexible? Find out the best times to travel from St. Louis to Heathrow based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking St. Louis to London Heathrow Airport flights

  • What is the cheapest flight from St. Louis to London Heathrow Airport?

    In the last 5 days, the lowest price for a flight from St. Louis to London Heathrow Airport was $320 for a one-way ticket and $1,071 for a round-trip.

  • Do I need a passport to fly between St. Louis and London Heathrow Airport?

    A passport is required to fly from St. Louis to London Heathrow Airport.

  • Which airports will I be using when flying from St. Louis to London Heathrow Airport?

    St. Louis and London Heathrow Airport are both served by 1 main airport. You will leave St. Louis from Lambert-St Louis and will be arriving at London Heathrow.

  • Which airlines offer Wi-Fi service onboard planes from St. Louis to London Heathrow Airport?

    American Airlines, Lufthansa, and United Airlines offer inflight Wi-Fi service on the St. Louis to London Heathrow Airport flight route.

  • Which aircraft models fly most regularly from St. Louis to London Heathrow Airport?

    The Boeing 787-8 Dreamliner is the aircraft model that flies most regularly on the St. Louis to London Heathrow Airport flight route.

  • Which airline alliances offer flights from St. Louis to London Heathrow Airport?

    SkyTeam, Star Alliance, and oneworld are the airline alliances operating flights between St. Louis and London Heathrow Airport, with SkyTeam being the most commonly used for this route.

  • On which days can I fly direct from St. Louis to London Heathrow Airport?

    You can catch a nonstop flight from St. Louis to London Heathrow Airport on Tuesday, Wednesday, Friday, and Sunday.

  • Which is the best airline for flights from St. Louis to London, Delta or KLM?

    The two airlines most popular with KAYAK users for flights from St. Louis to London are Delta and KLM. With an average price for the route of $852 and an overall rating of 7.9, Delta is the most popular choice. KLM is also a great choice for the route, with an average price of $683 and an overall rating of 7.8.

  • How does KAYAK find such low prices on flights from St. Louis to London Heathrow Airport?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from St. Louis to London Heathrow Airport.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from St. Louis to London Heathrow Airport?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to London Heathrow Airport from St. Louis is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from St. Louis to London Heathrow Airport?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to London Heathrow Airport with an airline and back to St. Louis with another airline. Booking your flights between St. Louis and LHR can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from St. Louis to London Heathrow Airport?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to London Heathrow Airport from St. Louis up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

KAYAK’s top tips for finding a cheap flight from St. Louis to London Heathrow Airport

  • Looking for a cheap flight? 25% of our users found flights on this route for $374 or less one-way and $1,071 or less round-trip.

Prefer to fly direct from St. Louis to London Heathrow Airport?

 
Direct data is based off flight results for the next 60 days. Find direct flights from all airlines flying direct from Lambert-St Louis to London Heathrow.
Find which airlines fly direct from Lambert-St Louis Airport to London Heathrow Airport, which days they fly and book direct flights.

Direct departures

Lambert-St Louis to London Heathrow

Tuesday

British Airways

British Airways

Wednesday

British Airways

British Airways

Friday

British Airways

British Airways

Sunday

British Airways

British Airways

See more direct flights

Direct returns

London Heathrow to Lambert-St Louis

Tuesday

British Airways

British Airways

Wednesday

British Airways

British Airways

Friday

British Airways

British Airways

Sunday

British Airways

British Airways

See more direct flights

Reviews of the top 5 airlines serving from St. Louis to Heathrow

 
See real verified KAYAK customer reviews for airlines flying from St. Louis to London. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from St. Louis to Heathrow? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.4
United AirlinesOverall score based on 9828 reviews
7.1Entertainment
7.7Boarding
6.6Food
8.1Crew
7.3Comfort
Airline reviews

Our flight was delayed several Times due to mechanical issues. Although I understand this may happen at times, it was very inconvenient and we had to book a hotel for an overnight stay. We were traveling with my 3-yo grandson and waiting at the airport from noon until 6:30pm with no reassurance that our next rescheduled flight would depart, we had to decide what’s best for him. A day later, I found out that I may be able to demand compensation if my flight is delayed more than 4 hours. I will hav to read the fine print next time.

4.0 OkayOlivia, Jun 2026
SEA - SFO
Read more United Airlines reviews

Our flight was delayed several Times due to mechanical issues. Although I understand this may happen at times, it was very inconvenient and we had to book a hotel for an overnight stay. We were traveling with my 3-yo grandson and waiting at the airport from noon until 6:30pm with no reassurance that our next rescheduled flight would depart, we had to decide what’s best for him. A day later, I found out that I may be able to demand compensation if my flight is delayed more than 4 hours. I will hav to read the fine print next time.

Flight cancelled instead of leaving Friday am now, maybe, leaving Sunday

The pilot had to extend the flight time from san antonio to Houston to burn off fuel. This caused a lot of unnecessary stress since we had a tight connection to Aruba. And with no other flights going to Aruba we were worried about spending a night in Houston. We had to to run to our connection because of the flight crews mistake. Not happy.

Service was professional and quick. Premium economy seat was comfortable given the class

one of the flight attendants on the Dallas to frankfurt leg was somewhat rude..

I'm a United 1K member and have ben for 10 years. The gate agent had no control over the boarding process and had us passengers queued for hours as delays were announced. On the plane, the overhead air nozzle was broken so col over was powering through on me and the passenger next to me. Not a great experience for a million miler on United. Feel free to contact me. Josh Smigel - DM426089

Like: departed and arrived on time. Unlike: Food options for purchase allways bad, 1 of 2 of the crew members not very friendly at all. Seats and leg room aweful. At this point I am thinking on switching to AA.

Over 5 hour delay with minimal updates or ability to standby for alternative flights. During boarding and 1 hr+ wait for takeoff, seats were drenched w water from air conditioning condensation and always leftover crumbs on carpet and seats

It was perfect! United Airlines staff was extremely caring, super friendly and professional

The staff was extremely helpful and friendly at all times! They went above and beyond to get us into an earlier flight in San Diego to make our connection in SFO possible, because our original flight did actually not make it! I did so much appreciate the UA team and how they made this possible. We also didn’t have seats together on the long flight to Singapore, but they found us seats together last moment with no additional cost! Nobody sat next to us, so that we were able to sleep! Thanks to UA for improving their service and Underpricer for booking this trip! Please be careful: 1,5 hrs for transfer in San Francisco might not be enough time in the future

Luggage did not make it onto my plane. Business seats were economy with empty row seat. Just horrible experience. Why would the company allow for transfers that don’t give employees enough time to transfer luggages??

For an long range economy flight I feel more space and more meal options need to be offered for flights over 5 hours

The check in agents in PHL and gate agents had to have been the rudest women that I have ever encountered; the agent weighing the bags at check in screamed continuously at all of the guests as did the woman at the gate.I have Executive Platinum status with AA and fly a lot with AA but these ladies were the absolute worst I had the displeasure to encounter!

B-class on an old plane with antiquated amenities and poor service. Landed in Rome w/o bag that didn’t make the connection (plenty of time in London). Bag will come to hotel NOT the day it lands but the following night!! Still waiting for bag…BA had nothing to offer in support and couldn’t even tell me their comp, told to submit receipts and then I’ll learn what is or isn’t covered.

It's a long flight and that is always difficult. I was comfortable and well. The movies available were great and the crew was good.

Premium Economy Good crew, good service, excellent food. Seat back screen just not bright enough.

Flight was delayed an no one cares, or try to help passengers to get the conexión.

Our flight was cancelled while we are on our way to the airport. So, no notice. We were rescheduled to another airline with a 2 hour later takeoff and so arrived at our destination on time. We pre-paid American Airlines $190 to upgrade our seats. No refund. So no use for AA or Kayak.

Terrible, horrible, disappointing- without telling us they changed planes and moved and separated our seats to opposite sides - said they changed seats putting us together - got to airport to find no, they did not - we sat opposing sides of plane - food overly salty to inedible, never saw stewardess but once - it was terrible

The business class layout of chairs was weired. You are sitting directly across stranger.,

Flight was overbooked and seats assigned to multiple passengers. Delay 1 hour to sort out.

Good but I don’t received my bags yet is been 5days still no update

It was pretty straight forward, no glitches or hidden costs

It was a short flight so, everything went smoothly and we got to where we needed to be safely.

Didn’t make it on the flight. Delayed then had to be rebooked, which in turn had me waiting at the airport for another 8 hours before next flight

No TV on the flight. The charging outlet was not working. No food, even a sandwich. The served orange was poor quality.

Selected seats 5 months prior to date. Had email confirmation and seats were not honoured. Family did not sit together

Loved and was pleasantly surprised by the food!! Request Lufthansa to help transiting passengers at Munich (confusion whether to go thru passport control or not).

The flight was comfortable and the staff were helpful and friendly. However, we did not know we were flying PAL until we arrived in Canada, so it was a bit disconcerting. In addition, which port we were leaving from was confusing.

I cannot think how they could put more seats together but they did. So elbow to elbow leg to leg for these long journeys they should consider leg space at least. Since they did not offer to check people's carry one space was tight and if you did not get on first people used your assigned overhead storage so now your doing these same to another. Cascading inconvenience.

Not bad but they lost 2 of my bags when I got to Florence

Couldn’t get boarding passes online, delayed an hour, and smallest amount of space on board I’ve ever encountered for such a long flight.

Horrible seat at the back. Crew was very kind. Packed plane. Wordy pilot bragging about Iberia being punctual when many of us came from Alicante flight that was delayed an hour and many lost connection and we lost our luggage. Still waiting for it

In general, I've had excellent experiences with Iberia flights and will continue to use them. In this last flight there were two things that didn't go right. I didn't get the kosher meal I had pre-requested when I had checked in on-line. Things worked out OK as we ended up eating the fish and vegetarian choices, which were really good. The other issue was that some movies for me and my wife started fine but after 8-12 minutes the content just switched to something else. The flight attendant reset our entertainment systems, but the problem persisted. We ended up choosing other movies/TV shows that did work fine.

Flight was fine - however my husband's checked in case was damaged, and mine still has not arrived

Awful. They didn't even show concern that her connecting flight( Dallas to Mardrid) was gone/missing. I don't understand how that is even possible. Rudest answer from one of the crew was that American Airlines sold the tickets to somebody else. My daughter was not in the list.

The flight was canceled on a Thursday last minute. I lost thousands of dollars in hotels and car rental

Excellent lie flat seat for premium economy! Great staff. Bad food . Not so great entertainment. My bag didn’t make it either.

Really like the idea experience on this airline I will use again

The boarding procedure got confusing because they wanted to weigh everyone’s carry-on. Apparently mine was 3 1/2 kg over their limit. I didn’t know they had a limit. And at the check-in desk, nothing was said about this. They wanted me to check the carry-on at no charge and that would have been fine except then they told me at my connection in London I would have to go outside to baggage claim retrieve my bag, and then recheck it. In other words, they could not check it to my final destination, only to London. I told him this was unacceptable so after a few minutes of discussion, they came back and said that my bag would be OK to carry on the plane. It seems that if you have a connection then the weight is not as important. Then when I actually went to board the boarding agent said I needed a tag indicating that my bag had been weighed, even though she had just five minutes ago talked to the same person who cleared me. Lots of confusion seems like a very bad process. They need to improve this.

Boarding process was chaotic. Confusion over Boarding gates: gate 55 or gate 56 ???. Unnecessary standing in long lines to board. Better to call out Boarding groups one at a time and everyone else to sit. Airline only has 2 Boarding groups 1-3 and 4-9. That causes over crowding and chaos

Lady next to me was coughing profusely the entire flight, other lady moved seats because of it, 8 hours of that during an overnight flight is a bit much.

3.5 hr delay leaving Pittsburgh, notifications for which were incomplete and untimely. Connecting flight was automatically switched to one requiring more than a 30 hour layover! After waiting in a long queue, customer service reduced layover to 11 hours and also set up an earlier standby. The standby had empty seats, but the gate agent couldn't change our tickets! On top of all that my luggage was lost and has yet to even be located, much less returned 5 (FIVE!) days later. Too bad there's no rating below poor.

Canceled flight late London to Florence. Help at airport very poor. Treated poorly. Had to sleep in the airport. Lost bags- still do not have them. Horrible. I should be reimbursed!

The seats are extra cramped if you are taller than 5’8! Spring for the extra legroom seats for sure if you have a long flight!

Very disappointed with British Airways. It has been over 24 hours and I still have not received my checked baggage or any proper update. Customer support has been unresponsive, making the situation even more frustrating. Poor baggage handling and lack of communication seriously impacted my travel experience.

Flight was good but temp in the cabin was cold.

I like American Airlines and their safety record. They provide quality service and a feel safe enough to prefer American Airlines over other carriers even if I have to pay a little more.

Cancelled flight and re booked seats were a downgrade. British Airways said the upgrade was t available but when I checked it was but then they wouldn’t make it right

Boarding was orderly, pilot and flight attendants were nice, entertainment options were good, and low sodium meals were quite tasty.

Everything you need to know for your flight from St. Louis to Heathrow

Information on your arrival and departure airports