$415 Cheap United flights St. Louis (STL) to Eureka (ACV)

Use the "Price (lowest to highest)" filter on Expedia to search for cheap United Airlines return flights from $309 from STL to ACV. Affordable one-way tickets from $415 are also available.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.

For cheap United Airlines fares from Lambert-St. Louis Intl. Airport (STL) to Arcata - Eureka Airport (ACV), start searching one to three months before your intended departure. Securing domestic flights 34 to 86 days in advance could save you 25% compared to booking just 6 to 12 days ahead. The day you book can also influence the cost. Sunday is typically the cheapest, while Monday is often the most expensive for domestic flights. You can save 6% on average by booking your trip on a Sunday.**Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC's global airline sales database.

To find the earliest departure from STL to ACV with United Airlines, filter your results by "Morning" and "Early Morning." Choosing an early flight generally means you're less likely to experience cancellations.**Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.

With a rewarding loyalty program, United Airlines is a popular choice for many passengers flying from STL to ACV. Plus, if you're a United Mileage Plus and One Key™ member booking through Expedia, you can earn OneKeyCash™* on eligible flights along with your airline miles.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.