Cheap flights from St. Louis to Phoenix from $62

If you are unable to visit Phoenix during the month of January, then departing from St. Louis during the month February is also very affordable. Most momondo users find prices during this month for around $354.

On average, the least expensive day to fly to Phoenix from St. Louis is on a Friday. momondo users have found tickets for Friday departures for as low as $430. However, this price may fluctuate depending on the airline, the season, and holidays. On the other hand, Sunday is the most expensive day to depart from St. Louis because it is more convenient for both business and leisure travelers. As a result, prices tend to be around $515.

The cheapest time of day to fly to Phoenix is in the evening when flights can be purchased for as low as $335. In the morning is when there is more demand to fly to Phoenix, so prices are often more expensive at around $490 per ticket.

Fly from Lambert-St Louis to Phoenix Sky Harbor Intl for the best Lambert-St Louis - Phoenix flight prices

You are more likely to see cheaper flights to Phoenix from St. Louis when booking weeks ahead of your departure date. In general, you can expect to find flights to Phoenix for around $400 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Phoenix from St. Louis for as low as $364 on momondo.

There are 4 cabin classes available to choose from on St. Louis to Phoenix flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Frontier and Southwest are the most popular carriers operating from Lambert-St Louis to Phoenix

Southwest, American Airlines and Frontier are the top three most popular airlines that fly to Phoenix from St. Louis according to our data. Southwest is the first choice among our users, with 42% of people opting to fly with this airline when traveling to Phoenix. Keep in mind that there are 5 different airlines that fly to Phoenix on a routine basis, so you have a few additional options to choose from.

The number of flights available between St. Louis and Phoenix is 2 per day as of October 2026. The most frequent departure time is 8:00AM, with 42% of daily flights leaving at noon.

The number of flights available between St. Louis and Phoenix is 15 per week as of October 2026. The most frequent departure day is Thu, with 53% of weekly flights leaving on this day.