Find cheap Frontier flights to Illinois
LAX — ORD
Oct 4 — Oct 111
Round-trip
1 adult, Economy
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Cheapest Frontier flights from USA to IllinoisExplore the most affordable Frontier flight options available from USA to Illinois. Find the lowest fares with prices last updated on September 4, 2026.
Explore the most affordable Frontier flight options available from USA to Illinois. Find the lowest fares with prices last updated on September 4, 2026.
This Super.com deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/285:02 pm -
Nonstop2h 21m
Thu 10/110:26 am -
Nonstop2h 10m
Deal found 9/3![Frontier logo]()
$136
This Cheapflightsfares deal was found by Cheapflights users on 9/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/56:38 pm -
Nonstop2h 30m
Sat 9/126:20 am -
Nonstop2h 09m
Deal found 9/1![Frontier logo]()
$137
This Super.com deal was found by Cheapflights users on 9/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/910:35 am -
Nonstop2h 16m
Thu 9/247:28 pm -
Nonstop2h 16m
Deal found 9/2![Frontier logo]()
$138
Best Frontier flights from USA to IllinoisDiscover carefully curated Frontier flight deals from USA to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 4, 2026.
Discover carefully curated Frontier flight deals from USA to Illinois that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 4, 2026.
This CheapOair deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/19:08 pm -
1 stop25h 31m
Sat 10/36:20 am -
Nonstop2h 09m
Deal found 9/3![Frontier logo]()
$141
This Cheapflightsfares deal was found by Cheapflights users on 9/4. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/308:00 am -
Nonstop2h 17m
Tue 11/37:28 pm -
Nonstop2h 16m
Deal found 9/4![Frontier logo]()
$156
This Super.com deal was found by Cheapflights users on 9/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/18:00 am -
Nonstop2h 20m
Wed 10/77:28 pm -
Nonstop2h 16m
Deal found 9/1![Frontier logo]()
$162
Direct Frontier flights from USA to IllinoisExplore non-stop Frontier flight options from USA to Illinois based on user searches, and compare prices and availability for your desired travel dates. Data last updated September 4, 2026.
Explore non-stop Frontier flight options from USA to Illinois based on user searches, and compare prices and availability for your desired travel dates. Data last updated September 4, 2026.
This Super.com deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/285:02 pm -
Nonstop2h 21m
Thu 10/110:26 am -
Nonstop2h 10m
Deal found 9/3![Frontier logo]()
$136
This Cheapflightsfares deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/26:52 pm -
Nonstop2h 24m
Tue 12/88:10 am -
Nonstop2h 16m
Deal found 9/3![Frontier logo]()
$138
This Cheapflightsfares deal was found by Cheapflights users on 9/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/18:00 am -
Nonstop2h 20m
Thu 10/87:44 pm -
Nonstop2h 23m
Deal found 9/2![Frontier logo]()
$141
Last-minute Frontier flights from USA to IllinoisDiscover last-minute Frontier flight deals from USA to Illinois. Data last updated September 4, 2026 and is based on user searches.
Discover last-minute Frontier flight deals from USA to Illinois. Data last updated September 4, 2026 and is based on user searches.
This Super.com deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/285:02 pm -
Nonstop2h 21m
Thu 10/110:26 am -
Nonstop2h 10m
Deal found 9/3![Frontier logo]()
$136
This Cheapflightsfares deal was found by Cheapflights users on 9/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/56:38 pm -
Nonstop2h 30m
Sat 9/126:20 am -
Nonstop2h 09m
Deal found 9/1![Frontier logo]()
$137
This Super.com deal was found by Cheapflights users on 9/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/910:35 am -
Nonstop2h 16m
Thu 9/247:28 pm -
Nonstop2h 16m
Deal found 9/2![Frontier logo]()
$138
One-way Frontier flights to IllinoisSearch for one-way Frontier flight options to Illinois. Find affordable one-way fares based on user searches. Data last updated September 4, 2026.
Search for one-way Frontier flight options to Illinois. Find affordable one-way fares based on user searches. Data last updated September 4, 2026.
This Kiwi.com deal was found by Cheapflights users on 9/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/125:02 pm -
Nonstop2h 21m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/1![Frontier logo]()
$77
This Priceline deal was found by Cheapflights users on 9/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/2112:25 pm -
Nonstop2h 19m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/2![Frontier logo]()
$79
This Super.com deal was found by Cheapflights users on 9/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/25:02 pm -
Nonstop2h 21m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/2![Frontier logo]()
$82
Flights to Illinois with Frontier at a glance
Find detailed information about Frontier flights from USA to Illinois. Explore the options provided by Frontier to plan your journey from USA to Illinois. Data last updated September 4, 2026.
Popular in | June |
|---|---|
Cheapest in | January |
Average price | $184 |
Round-trip from | $136 |
One-way from | $77 |
Good round-trip deal | $202 or less |
Good one-way deal | $117 or less |
Cheapflights Insights
Find cheap Frontier flights to Illinois
US0-USIL
ATL-ORD
How long is the flight to Illinois with Frontier?
On average, Frontier flights from the United States to Illinois take 2 hours 18 minutes. Flights to Illinois from other popular cities in the United States will vary in length. Below are a few examples of popular routes and their flight times.
Frontier weekly flight availability to Illinois
The most flights to Illinois operated by Frontier are scheduled on a Sunday (17 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (10 on average).
When is the best time to book a flight to Illinois with Frontier?
The best time to book a flight to Illinois with Frontier is 35 days before departure. On average, fares are higher if you book on the same day as departure.
FAQs for Frontier flights to Illinois
Reviews from Frontier flights to Illinois
See what other users thought of their Frontier experience.
Overview
Reviews
Frontier
2,624 reviews
Overview
Food
4.5
Entertainment
4.2
Comfort
5.4
Boarding
5.9
Crew
6.5
Recent reviews
2.0
|Jul 2026Flight was delayed a whole day - no compensation on food or drinks. Gate staff gave an older gentleman a hard time about his confusion and concern regarding the overnight delay.
10.0
|Jul 2026Better Food and there was no entertainment . You guys could provide head phones and wifi for the passengers
2.0
|Jul 2026Flight delayed 3 hours
6.0
|Jun 2026Nothing. Needs better seat. Need atleast water. Need wifi
4.0
|Jun 2026The flight was delayed about 3hours
1 out of 875
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