Cheap flights from London Heathrow Airport to St. Louis from $406
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 6/25. 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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British Airways flights from London Heathrow Airport to St. Louis
Our best British Airways deals on London Heathrow Airport to St. Louis flight tickets
Delta flights from London Heathrow Airport to St. Louis
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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?
In general, February is the cheapest month to fly from London Heathrow Airport to St. Louis. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $811. The month of September is another great option to travel to St. Louis, with average flight prices from London Heathrow Airport averaging around $828.
What is the cheapest day to depart on your flight to St. Louis?
The cheapest day to depart on your flight to St. Louis is on a Wednesday when prices can be found for as low as $952. This is often the case because there is less demand to fly during this day of the week. If your travel schedule is flexible, try to avoid departing on a Saturday because tickets tend to average around $1,371. These prices are subject to change though, so be sure to set up a Price Alert for flights to St. Louis.
What is the cheapest time of day to depart on your flight to St. Louis?
Flying to St. Louis from London Heathrow Airport at noon is the least expensive time of day to depart. momondo users have found prices as low as $1,075 when looking at flights departing at noon. In the morning is when there is more demand to fly to St. Louis, so prices are often more expensive at around $1,229 per ticket.
How far in advance should I book a flight to St. Louis?
You are more likely to see cheaper flights to St. Louis from London Heathrow Airport when booking 4 weeks ahead of your departure date. In general, you can expect to find flights to St. Louis for around $952 when searching 4 weeks out.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 $827 on momondo.
Can stopping save me money on London Heathrow Airport to St. Louis flights?
You could potentially save up to 15% 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 June 2025, prices for London Heathrow Airport to St. Louis flights are approximately 5% more expensive when compared to flights at the same time last year.
What is the cheapest airline that flies from London Heathrow to Lambert-St Louis?
Aer Lingus, Finnair, and Lufthansa are the most popular carriers operating from London Heathrow to Lambert-St Louis
What airlines fly to St. Louis?
American Airlines, British Airways and United Airlines are the top three most popular airlines that fly to St. Louis from London Heathrow Airport according to our data. American Airlines is the first choice among our users, with 28% of people opting to fly with this airline when traveling to St. Louis. Keep in mind that there are 4 different airlines that fly to St. Louis on a routine basis, so you have a few additional options to choose from.
When to book flights from London Heathrow Airport to St. Louis
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
How far is London Heathrow to Lambert-St Louis by plane?
The straight-line distance from London Heathrow to Lambert-St Louis is 4185.8 mi. By plane, this route typically takes 11h 46m.
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?
The number of operators available for flights from London Heathrow Airport to Lambert-St Louis Airport is 4 as of June 2025.
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 necessary travel and health documents for your Lambert-St Louis Airport trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.
What is the most popular airline from London Heathrow Airport to St. Louis?
Based on momondo bookings for this flight route, the most popular airline on flight routes from London Heathrow Airport to St. Louis is American Airlines (28% of total bookings). The next most popular airlines are British Airways (26%), United Airlines (26%), and Lufthansa (20%).
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 | ||
|---|---|---|---|---|---|
| PriceFrom $278 | Free Cancellation | Rating 7.2 10,000 reviews | |||
| PriceFrom $555 | Free Cancellation | Rating 6.6 7,008 reviews | |||
| PriceFrom $925 | Free Cancellation | Rating 6.7 7,139 reviews | |||
| PriceFrom $952 | Free Cancellation | Rating 7.4 8,790 reviews |
Traveling to a place near St. Louis?
Book flights to St. Louis if you plan to visit one of these locationsWhy use momondo?
Why should I use momondo to find a flight deal from London to St. Louis?
It is quick and easy to find London to St. Louis flights on momondo. We search and return numerous flight options from various airlines and agents. You can then use our filters to narrow your search until you have found the most convenient flight to St. Louis that suits 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?
Once you have performed a search in the form on the page, momondo provides useful filters and insights. We can show you the cheapest days and times to fly as well as help filter your options to help you make an informed choice when booking flights to St. Louis from London.
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.