Cheap flights from St. Louis to Las Vegas from $78

The month of January is, on average, the cheapest month to fly to Las Vegas from St. Louis, with most prices found around $253. The month of October is another great option to travel to Las Vegas, with average flight prices from St. Louis averaging around $264.

Our data shows that Monday is the least expensive day to fly to Las Vegas. Tickets to fly out on this day can be as low as $270. Flights from St. Louis to Las Vegas on a Wednesday will generally be more expensive and average around $406. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.

The cheapest time of day to fly to Las Vegas is in the evening when flights can be purchased for as low as $255. Flights to Las Vegas are more costly in the morning, with an average ticket price of $478. Departure times in the morning fall within the peak daily travel times, which is why tickets can be more expensive.

Fly from Lambert-St Louis to Las Vegas Harry Reid Intl for the best Lambert-St Louis - Las Vegas Harry Reid Intl flight prices

You are more likely to see cheaper flights to Las Vegas from St. Louis when booking weeks ahead of your departure date. In general, you can expect to find flights to Las Vegas for around $298 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Las Vegas from St. Louis for as low as $258 on momondo.

Frontier, United Airlines, and Alaska Airlines are the most popular carriers operating from Lambert-St Louis to Las Vegas Harry Reid Intl

Frontier, Southwest and American Airlines are the top three most popular airlines that fly to Las Vegas from St. Louis according to our data. Frontier is the first choice among our users, with 67% of people opting to fly with this airline when traveling to Las Vegas. Keep in mind that there are 9 different airlines that fly to Las Vegas on a routine basis, so you have a few additional options to choose from.

Historically, on average around 16% of flights between St. Louis and Las Vegas have experienced a delay on any given week. The average delay length over the past 12 months has been 128 minutes.

Generally, flights departing in the morning tend to experience fewer delays. Flights in the evening have, in the past, seen delays more frequently in comparison.

Wednesday is statistically the day of the week which experiences the fewest number of delays on this flight route. Sunday has historically seen more delays on average compared to the rest of the week.

According to our data, Southwest have had the least number of delays on this route over the last 12 months; with about 16% of their flights experiencing any sort of delay.

Denver (DEN) was the most common stop: 65% of momondo users choosing 1-stop flights on this route connected there.

Flights via Dallas (DFW) offer the lowest average round-trip price of $214.

Flights connecting via Salt Lake City (SLC) have the shortest average one-way travel time: 5h 51m.

Salt Lake City (SLC) has the shortest average layover time for this route: 1h 05m.

4 flights are operational daily from St. Louis to Las Vegas as of May 2026. The most popular departure time for this route is 1:00PM, with 37% of flights per day taking off at noon.

The number of flights available between St. Louis and Las Vegas is 29 per week as of May 2026. The most frequent departure day is Sun, with 31% of weekly flights leaving on this day.