Illinois

$55+ Cheap flights from Raleigh (RDU) to Illinois

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 4/1. Fares are subject to change and may not be available on all flights or dates of travel.
RDU — ORD
Feb 10 — Feb 171
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Cheap flight deals from Raleigh to Illinois

Discover tips and strategies to find the most affordable flight options for your journey from Raleigh (RDU) to Illinois (USIL). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated February 5, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$118
(CheapOair)

One-way from

$55
(Frontier)

Popular in

December

Cheapest in

August

Average price

$288

Good round-trip deal

$341 or less

Good one-way deal

$190 or less
Provider with most accurate pricing for Raleigh-Durham-Chicago (CHI) flight deals.
Provider most trusted by Cheapflights users for Raleigh-Durham-Chicago (CHI) flights.
From Raleigh-Durham to Illinois
One-way flight from Raleigh-Durham to Illinois
Highest demand for flights based on searches. 18% potential increase in price ($54 potential increase over avg. RT price).
Cheapest flight prices on average. 3% potential price decrease ($10 potential savings vs. average RT price).
Average for round-trip flights in February 2025
Price to beat on a round-trip flight from Raleigh-Durham to Illinois.
Price to beat on a one-way flight from Raleigh-Durham to Illinois.

Find flight deals from Raleigh to Illinois

Cheapest flights from Raleigh to Illinois
Explore the most affordable flight options available from Raleigh to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on February 5, 2025.

This CheapOair deal was found by Cheapflights users on 2/5. 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.
Tue 3/41:47 pmRDU - STL
1 stop10h 56mFrontier
Wed 3/55:20 pmSTL - RDU
1 stop26h 56mFrontier
Deal found 2/5$118
This CheapOair deal was found by Cheapflights users on 2/4. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/59:34 pmRDU - STL
1 stop20h 08mSpirit Airlines
Sun 3/95:38 pmSTL - RDU
1 stop25h 51mSpirit Airlines
Deal found 2/4$149
This FlightHub deal was found by Cheapflights users on 2/3. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/19:53 pmRDU - ORD
1 stop12h 52mMultiple Airlines
Mon 4/75:31 pmORD - RDU
1 stop5h 23mMultiple Airlines
Deal found 2/3$162
This Frontier deal was found by Cheapflights users on 2/4. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/810:15 pmRDU - ORD
1 stop12h 35mFrontier
Sun 5/111:01 pmORD - RDU
Nonstop2h 05mFrontier
Deal found 2/4$165
This CheapOair deal was found by Cheapflights users on 2/4. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/156:00 amRDU - MDW
1 stop8h 34mFrontier
Sun 5/184:00 pmMDW - RDU
1 stop15h 01mFrontier
Deal found 2/4$169
This Mytrip deal was found by Cheapflights users on 2/5. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/2010:58 amRDU - ORD
1 stop6h 29mSpirit Airlines
Wed 3/263:16 pmORD - RDU
2 stops17h 47mSpirit Airlines
Deal found 2/5$173
This Justfly.com deal was found by Cheapflights users on 2/4. 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 Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/269:53 pmRDU - STL
1 stop20h 59mMultiple Airlines
Wed 4/164:57 pmSTL - RDU
1 stop27h 19mMultiple Airlines
Deal found 2/4$186
This American Airlines deal was found by Cheapflights users on 2/4. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 2/1510:07 amRDU - MLI
1 stop6h 44mAmerican Airlines
Wed 2/195:00 amMLI - RDU
1 stop4h 29mAmerican Airlines
Deal found 2/4$199
This Southwest deal was found by Cheapflights users on 2/4. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/267:15 pmRDU - STL
Nonstop2h 15mSouthwest
Wed 4/166:40 pmSTL - RDU
Nonstop1h 50mSouthwest
Deal found 2/4$257
This United Airlines deal was found by Cheapflights users on 2/5. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/209:30 amRDU - STL
1 stop5h 53mUnited Airlines
Mon 3/243:30 pmSTL - RDU
1 stop4h 38mUnited Airlines
Deal found 2/5$272
This Delta deal was found by Cheapflights users on 2/4. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/99:53 amRDU - MLI
1 stop7h 27mDelta
Wed 4/165:42 amMLI - RDU
1 stop7h 21mDelta
Deal found 2/4$274
This American Airlines deal was found by Cheapflights users on 2/4. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/275:55 amRDU - ORD
Nonstop2h 30mAmerican Airlines
Mon 3/32:09 pmORD - RDU
Nonstop2h 04mAmerican Airlines
Deal found 2/4$296

Find flights from Raleigh to Illinois within your budget

Customize your flight search to find flights from Raleigh to Illinois that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated February 5, 2025.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

RaleighSt. Louis

RDU - STL

RDUSTL

Raleigh-Durham

Tue 3/4

1:47 pm-11:43 pm

1 stop10h 56m

Lambert-St Louis

Wed 3/5

5:20 pm-9:16 pm

1 stop26h 56m

$118

RaleighSt. Louis

RDU - STL

RDUSTL

Raleigh-Durham

Wed 3/5

9:34 pm-4:42 pm

1 stop20h 08m

Lambert-St Louis

Sun 3/9

5:38 pm-8:29 pm

1 stop25h 51m

$149

RaleighChicago

RDU - ORD

RDUORD

Raleigh-Durham

Tue 4/1

9:53 pm-9:45 am

1 stop12h 52m

Chicago O'Hare Intl

Mon 4/7

5:31 pm-11:54 pm

1 stop5h 23m

$162

RaleighChicago

RDU - ORD

RDUORD

Raleigh-Durham

Thu 5/8

10:15 pm-9:50 am

1 stop12h 35m

Chicago O'Hare Intl

Sun 5/11

1:01 pm-4:06 pm

Nonstop2h 05m

$165

RaleighChicago

RDU - MDW

RDUMDW

Raleigh-Durham

Thu 5/15

6:00 am-1:34 pm

1 stop8h 34m

Chicago Midway

Sun 5/18

4:00 pm-8:01 am

1 stop15h 01m

$169

RaleighChicago

RDU - ORD

RDUORD

Raleigh-Durham

Thu 3/20

10:58 am-4:27 pm

1 stop6h 29m

Chicago O'Hare Intl

Wed 3/26

3:16 pm-10:03 am

2 stops17h 47m

$173

RaleighSt. Louis

RDU - STL

RDUSTL

Raleigh-Durham

Wed 3/26

9:53 pm-5:52 pm

1 stop20h 59m

Lambert-St Louis

Wed 4/16

4:57 pm-9:16 pm

1 stop27h 19m

$186

RaleighMoline

RDU - MLI

RDUMLI

Raleigh-Durham

Sat 2/15

10:07 am-3:51 pm

1 stop6h 44m

Moline Quad-City

Wed 2/19

5:00 am-11:56 am

1 stop5h 56m

$199

RaleighSt. Louis

RDU - STL

RDUSTL

Raleigh-Durham

Wed 3/26

7:15 pm-8:30 pm

Nonstop2h 15m

Lambert-St Louis

Wed 4/16

6:40 pm-9:30 pm

Nonstop1h 50m

$257

RaleighSt. Louis

RDU - STL

RDUSTL

Raleigh-Durham

Thu 3/20

9:30 am-2:23 pm

1 stop5h 53m

Lambert-St Louis

Mon 3/24

3:30 pm-9:08 pm

1 stop4h 38m

$272

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/3

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Best time to book a flight from Raleigh to Illinois

Have a flexible travel schedule? Discover the best time to fly to Illinois from Raleigh with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Travel insights for flights from Raleigh to Illinois

Get recent, data-driven insights about flights from Raleigh to Illinois including ideal travel times, pricing trends, and more.

What is the cheapest month to book a flight from Raleigh to Illinois?

Currently, August is the cheapest month in which you can book a flight from Raleigh to Illinois (average of $245). Flying from Raleigh to Illinois in March is currently the most expensive (average of $323). 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.

What is the cheapest time of day to fly from RDU to IL?

Find hourly flight availability from Raleigh to Illinois. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated February 5, 2025.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Raleigh to Illinois as you normally would.

Weekly flight availability from Raleigh to Illinois

Explore weekly flight availability from Raleigh to Illinois. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated February 5, 2025.

The most flights from RDU to USIL are scheduled on a Monday (24 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (12 on average).

Rainfall in Illinois by month

Plan your trip to Illinois by taking into account the average rainfall totals by month.