Cheap flights from Massachusetts to St. Louis from $77

In general, August is the cheapest month to fly from Massachusetts to St. Louis. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $371. The month of September is another great option to travel to St. Louis, with average flight prices from Massachusetts averaging around $401.

The cheapest day to depart on your flight to St. Louis is on a Thursday when prices can be found for as low as $422. 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 Sunday because tickets tend to average around $501. These prices are subject to change though, so be sure to set up a Price Alert for flights to St. Louis.

Flying to St. Louis from Massachusetts in the evening is the least expensive time of day to depart. momondo users have found prices as low as $427 when looking at flights departing in the evening. At noon is when there is more demand to fly to St. Louis, so prices are often more expensive at around $477 per ticket.

Fly from Boston Logan Intl to Lambert-St Louis for the best Massachusetts - Lambert-St Louis flight prices

You are more likely to see cheaper flights to St. Louis from Massachusetts when booking weeks ahead of your departure date. In general, you can expect to find flights to St. Louis for around $461 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to St. Louis from Massachusetts for as low as $388 on momondo.

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

Southwest, United Airlines, and American Airlines are the most popular carriers operating from Massachusetts to Lambert-St Louis

American Airlines, Southwest and Delta are the top three most popular airlines that fly to St. Louis from Massachusetts according to our data. American Airlines is the first choice among our users, with 55% of people opting to fly with this airline when traveling to St. Louis. Keep in mind that there are 7 different airlines that fly to St. Louis on a routine basis, so you have a few additional options to choose from.

The number of flights available between Massachusetts and St. Louis is 3 per day as of April 2026. The most frequent departure time is 3:00PM, with 43% of daily flights leaving at noon.

The number of flights available between Massachusetts and St. Louis is 25 per week as of April 2026. The most frequent departure day is Mon, with 20% of weekly flights leaving on this day.