Discover cheap flights from Barcelona to St. Louis, MO with the Opodo search engine. By using our flight comparison tool, you'll be able to find your flight selection at the cheapest price available on the market. You can also filter price, timings, airports and more to find the best route to St. Louis, MO that suits your needs. Using our 'smart choice' option, Opodo's engine will find the cheapest and most convenient flight out of the list of results, letting you save time and money on booking your flight from Barcelona to St. Louis, MO. Additionally, you can also book a hotel or a car for hire to complete your booking process. You can also download the Opodo App to save on flights and receive exclusive discounts by subscribing to our newsletter. Let us help you book the perfect holiday, save money and effort by using Opodo's flight search engine and enjoy your holiday knowing you got the best flight deals. So remember, introduce your flight details, hit search and you're on your way! The perfect holiday is just around the corner, book now.