Cheap flights from St. Louis to Phoenix from $82

In general, December is the cheapest month to fly from St. Louis to Phoenix Sky Harbor Intl Airport. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $335. If you are unable to visit Phoenix Sky Harbor Intl Airport during the month of December, then departing from St. Louis during the month November is also very affordable. Most momondo users find prices during this month for around $335.

On average, the least expensive day to fly to Phoenix Sky Harbor Intl Airport from St. Louis is on a Wednesday. momondo users have found tickets for Wednesday departures for as low as $397. However, this price may fluctuate depending on the airline, the season, and holidays. 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 Phoenix Sky Harbor Intl Airport.

In the evening is the cheapest time of day to fly from St. Louis to Phoenix Sky Harbor Intl Airport when you can find flight prices for as low as $322. Flying to Phoenix Sky Harbor Intl Airport in the evening is an ideal time because this is during off-peak travel hours. Try not to purchase tickets in the morning because they tend to be around $473. Of course, these prices can vary depending on the time of year and what airport you fly to.

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

You are more likely to see cheaper flights to Phoenix Sky Harbor Intl Airport from St. Louis when booking weeks ahead of your departure date. In general, you can expect to find flights to Phoenix Sky Harbor Intl Airport for around $382 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Phoenix Sky Harbor Intl Airport from St. Louis for as low as $341 on momondo.

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

You could potentially save up to 6% on your flight if you consider stops on a St. Louis to Phoenix Sky Harbor Intl Airport flight.

As of September 2026, prices for St. Louis to Phoenix Sky Harbor Intl Airport flights are approximately 71% more expensive when compared to flights at the same time last year.

Southwest and Delta are the most popular carriers operating from Lambert-St Louis to Phoenix Sky Harbor Intl

Southwest, American Airlines and Frontier are the top three most popular airlines that fly to Phoenix Sky Harbor Intl Airport from St. Louis according to our data. Southwest is the first choice among our users, with 40% of people opting to fly with this airline when traveling to Phoenix Sky Harbor Intl Airport. Keep in mind that there are 5 different airlines that fly to Phoenix Sky Harbor Intl Airport on a routine basis, so you have a few additional options to choose from.

Salt Lake City (SLC) was the most common stop: 67% of momondo users choosing 1-stop flights on this route connected there.

Flights via Denver (DEN) offer the lowest average round-trip price of $236.

Flights connecting via Denver (DEN) have the shortest average one-way travel time: 5h 35m.

Salt Lake City (SLC) has the shortest average layover time for this route: 1h 28m.

As of September 2026, 4 flights take off from St. Louis and land in Phoenix Sky Harbor Intl Airport each day. The most common flight departure time for this route is 8:00AM, with 52% of daily flights taking off at noon.

The number of flights available between St. Louis and Phoenix Sky Harbor Intl Airport is 28 per week as of September 2026. The most frequent departure day is Mon, with 29% of weekly flights leaving on this day.