Cheap flights from St. Louis to Mexico from $126

If you’re not able to fly to Mexico in September, then October is your next best option. Flight prices from St. Louis to Mexico during October average around $397.

The cheapest day to depart on your flight to Mexico is on a Monday when prices can be found for as low as $387. 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 $488. These prices are subject to change though, so be sure to set up a Price Alert for flights to Mexico.

Our data shows that the cheapest St. Louis to Mexico flights are usually those with departure times in the morning. Our users have found flights to Mexico in the morning for as low as $433. If you have a flexible travel schedule, then try to avoid flying at noon when prices are $590 on average. Flights to Mexico from St. Louis at noon are generally more expensive because this time of day is more convenient for travelers’ schedules.

Fly from Lambert-St Louis to Cancun for the best Lambert-St Louis - Mexico flight prices

You are more likely to see cheaper flights to Mexico from St. Louis when booking weeks ahead of your departure date. In general, you can expect to find flights to Mexico for around $459 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Mexico from St. Louis for as low as $367 on momondo.

There is only 1 cabin class available to choose from on Lambert-St Louis to Mexico flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Frontier, Delta, and United Airlines are the most popular carriers operating from Lambert-St Louis to Mexico

Frontier, American Airlines and Southwest are the top three most popular airlines that fly to Mexico from St. Louis according to our data. Frontier is the first choice among our users, with 43% of people opting to fly with this airline when traveling to Mexico. Keep in mind that there are 9 different airlines that fly to Mexico on a routine basis, so you have a few additional options to choose from.

The number of flights available between St. Louis and Mexico is 2 per day as of March 2026. The most frequent departure time is 6:00AM, with 95% of daily flights leaving at noon.

20 flights are operational weekly from St. Louis to Mexico as of March 2026. The most popular departure day for this route is Mon, with 15% of flights per week taking off on this day.