Cheap flights from St. Louis to San Antonio from $88

If you aren’t able to travel during the month of May, then book flights to San Antonio from St. Louis during September instead. Flights to San Antonio in September, while not as cheap as those in May, still average around $307.

The cheapest day to depart on your flight to San Antonio is on a Saturday when prices can be found for as low as $348. This is often the case because there is less demand to fly during this day of the week. Be sure to avoid booking your departure on a Sunday as prices are generally higher than usual. According to our data, the average ticket price to San Antonio on Sunday is $477.

According to our data, the cheapest time of day to fly to San Antonio is in the afternoon. momondo users have found flights departing from St. Louis to San Antonio in the afternoon for as low as $362. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. Flights to San Antonio are more costly in the evening, with an average ticket price of $430. Departure times in the evening fall within the peak daily travel times, which is why tickets can be more expensive.

Fly from Lambert-St Louis to San Antonio for the best Lambert-St Louis - San Antonio flight prices

You are more likely to see cheaper flights to San Antonio from St. Louis when booking weeks ahead of your departure date. In general, you can expect to find flights to San Antonio for around $339 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to San Antonio from St. Louis for as low as $238 on momondo.

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

No. A direct flight is the cheapest option for a flight between St. Louis to San Antonio.

As of March 2026, prices for St. Louis to San Antonio flights are approximately 12% cheaper when compared to flights at the same time last year.

Delta and Southwest are the most popular carriers operating from Lambert-St Louis to San Antonio

Southwest, American Airlines and United Airlines are the top three most popular airlines that fly to San Antonio from St. Louis according to our data. Southwest is the first choice among our users, with 68% of people opting to fly with this airline when traveling to San Antonio. Keep in mind that there are 5 different airlines that fly to San Antonio on a routine basis, so you have a few additional options to choose from.

As of March 2026, 2 flights take off from St. Louis and land in San Antonio each day. The most common flight departure time for this route is 8:00AM, with 60% of daily flights taking off at noon.

The number of flights available between St. Louis and San Antonio is 16 per week as of March 2026. The most frequent departure day is Sun, with 25% of weekly flights leaving on this day.