Expect security screening at STL to take 5-10 minutes during off-peak times. Check real-time wait times online before heading to the airport.

Most accurate provider | CheapOair 3 stars |
|---|---|
Most trusted provider | CheapOair 3 stars |
Round-trip from | $171 (Kiwi.com) |
One-way from | $62 (Trip.com) |
Popular in | March |
Cheapest in | November |
Average price | $328 |
Good round-trip deal | $289 or less |
Good one-way deal | $129 or less |
Fly from
Fly to
Route
Depart
Return
Price
St. LouisPhoenix
STL - PHX
STLPHX
Lambert-St Louis
Tue 3/3
5:55 am-8:35 am
Nonstop3h 40m
Phoenix Sky Harbor Intl
Sun 3/8
5:00 am-9:50 am
Nonstop2h 50m
St. LouisPhoenix
STL - PHX
STLPHX
Lambert-St Louis
Fri 2/13
10:15 pm-12:45 am
Nonstop3h 30m
Phoenix Sky Harbor Intl
Tue 2/17
5:00 am-8:50 am
Nonstop2h 50m
St. LouisPhoenix
STL - PHX
STLPHX
Lambert-St Louis
Mon 2/23
9:55 am-7:21 pm
2 stops10h 26m
Phoenix Sky Harbor Intl
Thu 2/26
11:33 am-8:26 pm
2 stops7h 53m
St. LouisPhoenix
STL - PHX
STLPHX
Lambert-St Louis
Thu 1/22
6:30 am-4:53 pm
2 stops11h 23m
Phoenix Sky Harbor Intl
Thu 1/29
12:56 pm-10:58 pm
2 stops9h 02m
St. LouisPhoenix
STL - PHX
STLPHX
Lambert-St Louis
Thu 1/15
8:45 pm-11:15 pm
Nonstop3h 30m
Phoenix Sky Harbor Intl
Sun 1/18
6:55 am-10:45 am
Nonstop2h 50m
St. LouisPhoenix
STL - PHX
STLPHX
Lambert-St Louis
Mon 3/2
5:30 am-11:10 am
2 stops6h 40m
Phoenix Sky Harbor Intl
Thu 3/5
3:30 pm-10:10 pm
2 stops5h 40m
St. LouisPhoenix
STL - PHX
STLPHX
Lambert-St Louis
Fri 2/20
2:47 pm-10:56 am
1 stop21h 09m
Phoenix Sky Harbor Intl
Tue 2/24
3:40 pm-1:51 pm
2 stops21h 11m
St. LouisPhoenix
STL - PHX
STLPHX
Lambert-St Louis
Sat 2/28
8:41 am-7:21 pm
2 stops11h 40m
Phoenix Sky Harbor Intl
Mon 3/9
4:30 pm-11:34 pm
1 stop5h 04m
St. LouisPhoenix
STL - PHX
STLPHX
Lambert-St Louis
Fri 2/20
6:00 pm-10:50 pm
1 stop5h 50m
Phoenix Sky Harbor Intl
Mon 2/23
8:30 am-8:26 pm
2 stops10h 56m
St. LouisPhoenix
STL - PHX
STLPHX
Lambert-St Louis
Tue 1/6
7:00 am-1:09 pm
1 stop7h 09m
Phoenix Sky Harbor Intl
Sat 1/10
6:55 am-2:48 pm
1 stop6h 53m
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy2 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*1 star | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*1 star | |
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*1 star | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars |
Booking 69 days in advance of your planned departure date is, on average, the best time to get cheap flights from St. Louis to Phoenix Sky Harbor Intl Airport. The general trend is that the closer you book to the departure date, the more expensive your flight will be.
Currently, October is the cheapest month in which you can book a flight from St. Louis to Phoenix Sky Harbor Intl Airport (average of $107). Flying from St. Louis to Phoenix Sky Harbor Intl Airport in June is currently the most expensive (average of $235). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.
When flying from St. Louis to Phoenix Sky Harbor Intl Airport, the time of day you fly usually plays a role in the price. Save by searching for a flight in the evening, which can drop the price by up to 14% versus a flight in the morning.
Travelers seeking maximum savings on their St. Louis to Phoenix Sky Harbor Intl Airport flight should consider departing on Friday evenings when fares are most often at their lowest. Sunday evenings flights should be avoided if possible as fares are typically the most expensive at this time.
Orlando (MCO) – chosen by Cheapflights users on 50% of 1-stop itineraries from St. Louis to Phoenix Sky Harbor Intl Airport on Cheapflights.
Orlando (MCO) is the most affordable 1-stop option, with an average round-trip price of $140.
Flights via Las Vegas (LAS) have the shortest average one-way travel time for 1-stop routes: 7h 51m.
Flights via Las Vegas (LAS) offer the fastest connection on this route, with an average layover time of 2h 09m.
Crew
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Overall
Comfort
Food
Entertainment
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Thomas,Dec 2025
SEA - DEN
Crew
Boarding
Overall
Comfort
Food
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Thomas,Dec 2025
SEA - DEN
Crew
Boarding
Overall
Comfort
Food
Entertainment
Reviews
Thomas,Dec 2025
SEA - DEN
Crew
Boarding
Overall
Comfort
Food
Entertainment
Reviews
Thomas,Dec 2025
SEA - DEN
Crew
Boarding
Overall
Comfort
Food
Entertainment
Reviews
Thomas,Dec 2025
SEA - DEN
Crew
Boarding
Overall
Comfort
Food
Entertainment
Reviews
Thomas,Dec 2025
SEA - DEN
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$94 | Average$204 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$158 | Average$200 | FlexibilityNo cancel fee | On-time65% | |
| Cheapest$210 | Average$383 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$216 | Average$386 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$223 | Average$403 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$236 | Average$362 | FlexibilityNo cancel fee | On-timeN/A |