Cheap flights from London to St. Louis from £321

The month of August is, on average, the cheapest month to fly to St. Louis from London, with most prices found around £69. If you’re not able to fly to St. Louis in August, then September is your next best option. Flight prices from London to St. Louis during September average around £128.

Our data shows that Saturday is the least expensive day to fly to St. Louis. Tickets to fly out on this day can be as low as £602. Flights from London to St. Louis on a Sunday will generally be more expensive and average around £937. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.

Fly from London Heathrow to Lambert-St Louis for the best London - Lambert-St Louis flight prices

You are more likely to see cheaper flights to St. Louis from London when booking weeks ahead of your departure date. In general, you can expect to find flights to St. Louis for around £767 when searching weeks before you fly. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to St. Louis from London for as low as £644 on momondo.

There are 3 cabin classes available to choose from on London to St. Louis flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

You could potentially save up to 11% on your flight if you consider stops on a London to St. Louis flight.

Lufthansa, British Airways, and Delta are the most popular carriers operating from London to Lambert-St Louis

British Airways, United Airlines and Virgin Atlantic are the top three most popular airlines that fly to St. Louis from London according to our data. British Airways is the first choice among our users, with 49% of people opting to fly with this airline when travelling to St. Louis. Keep in mind that there are 9 different airlines that fly to St. Louis on a routine basis, so you have a few additional options to choose from.

Historically, on average around 0% of flights between London and St. Louis have experienced a delay on any given week. The average delay length over the past 12 months has been 0 minutes.

Generally, flights departing in the early afternoon tend to experience fewer delays. Flights departing in the early afternoon have, in the past, seen delays more frequently in comparison.

Chicago (ORD) was the most common stop: 33% of momondo users choosing one-stop flights on this route connected there.

Flights via Toronto (YYZ) offer the lowest average return price of £529.

Flights connecting via Toronto (YYZ) have the shortest average one-way travel time: 11h 32m.

Atlanta (ATL) has the shortest average stopover time for this route: 1h 44m.

2 flights are operational daily from London to St. Louis as of June 2026. The most popular departure time for this route is 16:00, with 100% of flights per day taking off in the afternoon.

As of June 2026, 20 flights take off from London and land in St. Louis each week. The most common flight departure day for this route is Tue, with 25% of weekly flights taking off on this day.