PHX

$29 Find Cheap Flights from Illinois to Phoenix

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight to Phoenix departing on 11/21. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Phoenix Sky Harbor Intl Airport

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Everything you should know

Cheapest round-trip
$145
Overall average: $373
Frontier
Wed 1/28Sun 2/1
STL - PHX • 1 stop
Cheapest non-stop
$147
Typical prices: $302-$497
Frontier
Fri 12/12Fri 12/19
STL - PHX • Non-stop
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Flight Deals
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Flight Deals

Cheap Flights from Illinois to Phoenix

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Illinois to Phoenix that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Illinois to Phoenix

Wed, Jan 28 - Sun, Feb 1
Frontier Logo
3:46 pm - 12:10 pmSTL-PHX
21h 24m1 stop
Frontier Logo
8:15 am - 12:08 pmPHX-STL
2h 53mnonstop
$145Frontier
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Thu, Jan 15 - Sun, Jan 18
Frontier Logo
9:47 pm - 8:20 amSTL-PHX
11h 33m1 stop
Frontier Logo
2:34 pm - 9:14 pmPHX-STL
5h 40m1 stop
$146Frontier
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Sat, Dec 6 - Sat, Dec 13
American Airlines Logo
2:37 pm - 5:06 pmSTL-PHX
3h 29mnonstop
American Airlines Logo
9:44 am - 1:51 pmPHX-STL
3h 07mnonstop
$149American Airlines
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Tue, Feb 3 - Thu, Feb 5
Multiple Airlines Logo
2:06 pm - 9:08 pmORD-PHX
8h 02m1 stop
Multiple Airlines Logo
2:05 pm - 6:48 pmPHX-ORD
3h 43mnonstop
$163Multiple Airlines
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Wed, Dec 3 - Thu, Dec 4
Multiple Airlines Logo
8:20 am - 11:49 pmORD-PHX
16h 29m2 stops
Multiple Airlines Logo
4:12 pm - 12:12 amPHX-ORD
7h 00m1 stop
$167Multiple Airlines
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Sat, Jan 31 - Sat, Feb 7
American Airlines Logo
5:16 pm - 11:57 pmPIA-PHX
7h 41m1 stop
American Airlines Logo
6:00 am - 4:59 pmPHX-PIA
9h 59m1 stop
$251American Airlines
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Fri, Dec 5 - Mon, Dec 8
Delta Logo
5:08 pm - 12:16 amMLI-PHX
8h 08m1 stop
Delta Logo
2:37 pm - 10:33 pmPHX-MLI
6h 56m1 stop
$269Delta
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Fri, Dec 5 - Mon, Dec 8
United Airlines Logo
5:40 pm - 10:57 pmMLI-PHX
6h 17m1 stop
United Airlines Logo
11:33 am - 9:11 pmPHX-MLI
8h 38m2 stops
$274United Airlines
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Wed, Feb 18 - Wed, Feb 25
United Airlines Logo
10:51 am - 6:59 pmMLI-PHX
9h 08m2 stops
United Airlines Logo
12:37 pm - 7:02 pmPHX-MLI
5h 25m1 stop
$287United Airlines
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Thu, Dec 11 - Tue, Dec 16
Delta Logo
3:30 pm - 12:16 amBMI-PHX
9h 46m1 stop
Delta Logo
11:43 am - 10:06 pmPHX-BMI
9h 23m1 stop
$429Delta
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Useful Info

Good to know

Low seasonAugust
Cheapest flight$29
Best time to beat the crowds with an average 13% drop in price.
Most popular time to fly with an average 10% increase in price.
Flight from St. Louis to Phoenix

Flights from Illinois to Phoenix: the best tips from KAYAK users

Insights shared by verified travelers who flew the route from Illinois to Phoenix 
Learn how KAYAK collects reviews and tips from users.
JanieFlew with SWISSORD-PHXFeb 2025
I think you should prebook food or bring your own food.
Verified travelerFlew with United AirlinesORD-PHXApr 2024
Use the find my gate feature on the flights phone app if available as the airport is a bit confusing

FAQs for booking Illinois to Phoenix flights

  • How does KAYAK find such low prices on flights from Illinois to Phoenix?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Illinois to Phoenix.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Illinois to Phoenix?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Phoenix from Illinois is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Illinois to Phoenix?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Phoenix with an airline and back to Illinois with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Illinois to Phoenix?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Phoenix from Illinois up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Traveling to a place near Phoenix?

Book flights to Phoenix if you plan to visit one of these locations
Paradise Valley
Globe
Cave Creek
Guadalupe
Morristown

Everything you need to know for your flight to Phoenix

Information on your arrival and departure airports

Phoenix (PHX)