What are the cheapest airlines to fly from Illinois to South Korea one-way?

$537 is the cheapest one-way deal found within the past few days, from Turkish Airlines. You may also be able to find cheap deals on Cathay Pacific and Air Canada, with prices starting from $553 and $582, respectively.

What is the cheapest month to fly from Illinois to South Korea?

Due to multiple factors, expect to potentially pay more when booking in December. For low rates, January can be a great choice for travel to South Korea. Flights to South Korea from Illinois in January are about $1,509 on average during January, but can be found for as low as $891.

Can I find deals for flights from Illinois to South Korea that include hotel bookings?

Yes. In addition to deals on Illinois to South Korea flights, Cheapflights offers vacation packages that include both flights and hotel.

How can I find direct flights from Illinois to South Korea?

After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Illinois to South Korea.

Can I find deals for business class flights from Illinois to South Korea?

Yes. Cheapflights offers flight deals from Illinois to South Korea by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

$1,170+ Flights from Illinois to South Korea

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Cheap flight deals from Illinois to South Korea

Most accurate provider	FlightHub 3 stars
Most trusted provider	FlightHub 3 stars
Round-trip from	$1,083 (FlightHub)
One-way from	$475 (Kiwi.com)
Popular in	December
Cheapest in	January
Average price	$1,186
Good round-trip deal	$947 or less
Good one-way deal	$537 or less

Provider with most accurate pricing for Chicago (CHI)-Seoul (SEL) flight deals.

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Provider most trusted by Cheapflights users for Chicago (CHI)-Seoul (SEL) flights.

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From Illinois to South Korea

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One-way flight from Illinois to South Korea

Search Deals

Highest demand for flights based on searches. 4% potential increase in price ($69 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 3% potential price decrease ($56 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in March 2025

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Price to beat on a round-trip flight from Illinois to South Korea.

Search Deals

Price to beat on a one-way flight from Illinois to South Korea.

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Find flight deals from Illinois to South Korea

Cheapest flights from Illinois to South Korea
Explore the most affordable flight options available from Illinois to South Korea. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 31, 2025.

Mon 4/2112:30 amORD - GMP

1 stop28h 45mEVA Air

Wed 5/78:20 pmGMP - ORD

1 stop38h 40mEVA Air

Deal found 3/30

$1,083

Sun 4/209:38 pmORD - ICN

1 stop28h 07mMultiple Airlines

Wed 5/712:45 pmICN - ORD

2 stops23h 14mMultiple Airlines

Deal found 3/30

$1,105

Thu 5/111:25 amORD - ICN

1 stop31h 15mTurkish Airlines

Sun 5/1111:20 pmICN - ORD

1 stop24h 20mTurkish Airlines

Deal found 3/30

$1,106

Tue 5/611:25 amORD - PUS

3 stops58h 20mMultiple Airlines

Tue 5/1312:45 pmPUS - ORD

3 stops34h 55mMultiple Airlines

Deal found 3/29

$1,111

Sun 4/1312:30 amORD - ICN

1 stop20h 30mEVA Air

Thu 5/812:00 pmICN - ORD

1 stop23h 00mEVA Air

Deal found 3/30

$1,112

Wed 4/304:00 pmORD - ICN

1 stop30h 40mCathay Pacific

Sun 5/1810:10 amICN - ORD

1 stop42h 15mCathay Pacific

Deal found 3/29

$1,114

Fri 9/265:30 pmORD - ICN

1 stop35h 15mWestJet

Tue 9/308:45 pmICN - ORD

1 stop33h 58mWestJet

Deal found 3/30

$1,152

Thu 9/251:30 pmSTL - ICN

2 stops36h 35mAir Canada

Thu 10/305:50 pmICN - STL

2 stops35h 36mAir Canada

Deal found 3/30

$1,196

Mon 5/511:25 amORD - CJU

2 stops40h 05mMultiple Airlines

Mon 5/1212:20 pmCJU - ORD

2 stops35h 20mMultiple Airlines

Deal found 3/30

$1,255

Sun 11/29:55 pmORD - ICN

2 stops42h 45mLOT

Wed 11/129:20 amICN - ORD

1 stop25h 40mLOT

Deal found 3/30

$1,274

Thu 9/257:36 pmSTL - ICN

2 stops25h 24mMultiple Airlines

Thu 10/3011:40 amICN - STL

2 stops40h 12mMultiple Airlines

Deal found 3/31

$1,298

Mon 4/2112:30 amORD - GMP

1 stop28h 45mMultiple Airlines

Thu 5/87:20 pmGMP - ORD

1 stop27h 55mMultiple Airlines

Deal found 3/30

$1,304

Best flights from Illinois to South Korea
Discover carefully curated flight deals from Illinois to South Korea that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated March 31, 2025.

Mon 4/2112:30 amORD - GMP

1 stop28h 45mEVA Air

Wed 5/78:20 pmGMP - ORD

1 stop38h 40mEVA Air

Deal found 3/30

$1,083

Sun 4/209:38 pmORD - ICN

1 stop28h 07mMultiple Airlines

Wed 5/712:45 pmICN - ORD

2 stops23h 14mMultiple Airlines

Deal found 3/30

$1,105

Thu 5/111:25 amORD - ICN

1 stop31h 15mTurkish Airlines

Sun 5/1111:20 pmICN - ORD

1 stop24h 20mTurkish Airlines

Deal found 3/30

$1,106

Wed 4/304:00 pmORD - ICN

1 stop30h 40mCathay Pacific

Sun 5/1810:10 amICN - ORD

1 stop42h 15mCathay Pacific

Deal found 3/29

$1,114

Wed 6/41:40 pmORD - ICN

2 stops39h 05mWestJet

Mon 6/98:45 pmICN - ORD

1 stop33h 59mWestJet

Deal found 3/30

$1,185

Thu 9/251:30 pmSTL - ICN

2 stops36h 35mAir Canada

Thu 10/305:50 pmICN - STL

2 stops35h 36mAir Canada

Deal found 3/30

$1,196

Thu 4/247:01 pmSTL - ICN

1 stop18h 59mDelta

Sat 5/316:40 pmICN - STL

1 stop18h 46mDelta

Deal found 3/31

$1,469

Tue 4/228:45 amORD - GMP

2 stops38h 20mAir China

Thu 5/82:25 pmGMP - ORD

2 stops28h 39mAir China

Deal found 3/30

$1,490

Thu 8/215:45 pmORD - GMP

1 stop27h 20mANA

Mon 9/17:55 pmGMP - ORD

1 stop26h 45mANA

Deal found 3/30

$1,602

Thu 9/257:00 amSTL - GMP

2 stops24h 50mJapan Airlines

Thu 10/307:50 amGMP - STL

2 stops22h 18mJapan Airlines

Deal found 3/30

$1,612

Sat 9/67:59 pmSTL - ICN

2 stops31h 06mQatar Airways

Fri 9/121:20 amICN - STL

2 stops50h 43mQatar Airways

Deal found 3/31

$1,668

Mon 5/56:45 pmMDW - ICN

2 stops31h 40mKLM

Mon 5/1210:25 pmICN - MDW

2 stops31h 05mKLM

Deal found 3/30

$1,734

Last-minute flights from Illinois to South Korea
Discover last-minute flight deals from Illinois to South Korea. Data last updated March 31, 2025 and is based on user searches.

Fri 4/46:00 amMDW - ICN

2 stops48h 50mMultiple Airlines

Fri 4/119:30 amICN - MDW

1 stop27h 02mMultiple Airlines

Deal found 3/30

$1,559

Sat 4/58:45 amORD - GMP

2 stops38h 20mAir China

Mon 4/282:25 pmGMP - ORD

2 stops28h 39mAir China

Deal found 3/29

$1,542

Sat 4/57:39 amMDW - ICN

2 stops42h 06mMultiple Airlines

Fri 4/119:30 amICN - MDW

1 stop27h 02mMultiple Airlines

Deal found 3/30

$1,668

Sun 4/67:50 pmORD - ICN

1 stop31h 50mTurkish Airlines

Tue 4/2211:20 pmICN - ORD

1 stop24h 20mTurkish Airlines

Deal found 3/30

$1,115

Sun 4/612:30 amORD - ICN

1 stop20h 30mEVA Air

Mon 7/712:00 pmICN - ORD

1 stop23h 10mEVA Air

Deal found 3/30

$1,163

Sun 4/612:30 amORD - GMP

1 stop27h 40mMultiple Airlines

Mon 4/217:55 amGMP - ORD

2 stops25h 33mMultiple Airlines

Deal found 3/30

$1,676

Mon 4/74:45 pmORD - ICN

3 stops29h 45mMultiple Airlines

Mon 4/219:45 pmICN - ORD

3 stops46h 00mMultiple Airlines

Deal found 3/30

$1,196

Mon 4/79:05 pmORD - ICN

2 stops29h 00mAir Canada

Mon 7/77:05 pmICN - ORD

2 stops26h 54mAir Canada

Deal found 3/30

$1,427

Mon 4/71:55 pmORD - ICN

1 stop30h 50mEtihad Airways

Sun 4/131:35 amICN - ORD

1 stop45h 10mEtihad Airways

Deal found 3/31

$1,772

Tue 4/88:45 amORD - ICN

2 stops41h 50mAir China

Mon 4/285:50 pmICN - ORD

2 stops25h 14mAir China

Deal found 3/29

$1,456

Tue 4/86:42 pmMDW - ICN

2 stops31h 43mKLM

Thu 4/1710:25 pmICN - MDW

2 stops32h 54mKLM

Deal found 3/30

$1,921

Tue 4/85:45 pmORD - GMP

1 stop38h 35mANA

Tue 4/297:55 pmGMP - ORD

1 stop26h 45mANA

Deal found 3/29

$1,976

One-way flights from Illinois to South Korea
Search for one-way flight options from Illinois to South Korea. Find affordable one-way fares based on user searches. Data last updated March 31, 2025.

Tue 4/229:38 pmORD - ICN

2 stops34h 22mMultiple Airlines

Deal found 3/30

$475

Tue 4/229:38 pmORD - GMP

3 stops44h 52mMultiple Airlines

Deal found 3/30

$520

Wed 4/98:50 pmMDW - ICN

3 stops55h 55mMultiple Airlines

Deal found 3/31

$529

Tue 4/2211:25 amORD - ICN

1 stop40h 15mTurkish Airlines

Deal found 3/30

$537

Wed 4/94:00 pmORD - ICN

1 stop30h 40mCathay Pacific

Deal found 3/31

$553

Fri 4/183:30 pmSTL - ICN

2 stops58h 35mAir Canada

Deal found 3/31

$582

Wed 5/215:30 pmORD - ICN

1 stop35h 15mWestJet

Deal found 3/31

$598

Thu 8/712:36 pmMLI - ICN

3 stops42h 34mMultiple Airlines

Deal found 3/29

$633

Tue 4/812:30 amORD - ICN

1 stop20h 30mEVA Air

Deal found 3/31

$637

Wed 4/236:30 amSTL - ICN

3 stops48h 45mMultiple Airlines

Deal found 3/31

$638

Mon 4/2112:30 amORD - GMP

1 stop28h 45mEVA Air

Deal found 3/30

$649

Sun 6/2911:50 amORD - PUS

3 stops56h 40mMultiple Airlines

Deal found 3/30

$667

Cheapflights Fare Finder

Use the filters below to find and compare flights from Illinois to South Korea that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

ChicagoSeoul

ORD - GMP

ORDGMP

Chicago O'Hare Intl

Mon 4/21

12:30 am-7:15 pm

1 stop28h 45m

Seoul Gimpo Intl

Wed 5/7

8:20 pm-9:00 pm

1 stop38h 40m

$1,083

ChicagoIncheon

ORD - ICN

ORDICN

Chicago O'Hare Intl

Sun 4/20

9:38 pm-3:45 pm

1 stop28h 07m

Incheon Intl

Wed 5/7

12:45 pm-9:59 pm

2 stops23h 14m

$1,105

ChicagoIncheon

ORD - ICN

ORDICN

Chicago O'Hare Intl

Thu 5/1

11:25 am-8:40 am

1 stop31h 15m

Incheon Intl

Sun 5/11

11:20 pm-9:40 am

1 stop24h 20m

$1,106

ChicagoBusan

ORD - PUS

ORDPUS

Chicago O'Hare Intl

Tue 5/6

11:25 am-11:45 am

3 stops58h 20m

Busan Gimhae

Tue 5/13

12:45 pm-9:40 am

3 stops34h 55m

$1,111

ChicagoIncheon

ORD - ICN

ORDICN

Chicago O'Hare Intl

Sun 4/13

12:30 am-11:00 am

1 stop20h 30m

Incheon Intl

Thu 5/8

12:00 pm-9:00 pm

1 stop23h 00m

$1,112

ChicagoIncheon

ORD - ICN

ORDICN

Chicago O'Hare Intl

Wed 4/30

4:00 pm-12:40 pm

1 stop30h 40m

Incheon Intl

Sun 5/18

10:10 am-2:25 pm

1 stop42h 15m

$1,114

ChicagoIncheon

ORD - ICN

ORDICN

Chicago O'Hare Intl

Wed 6/4

1:40 pm-6:45 pm

2 stops39h 05m

Incheon Intl

Mon 6/9

8:45 pm-4:44 pm

1 stop33h 59m

$1,185

St. LouisIncheon

STL - ICN

STLICN

Lambert-St Louis

Thu 9/25

1:30 pm-4:05 pm

2 stops36h 35m

Incheon Intl

Thu 10/30

5:50 pm-3:26 pm

2 stops35h 36m

$1,196

ChicagoJeju City

ORD - CJU

ORDCJU

Chicago O'Hare Intl

Mon 5/5

11:25 am-5:30 pm

2 stops40h 05m

Jeju City

Mon 5/12

12:20 pm-9:40 am

2 stops35h 20m

$1,255

St. LouisIncheon

STL - ICN

STLICN

Lambert-St Louis

Thu 9/25

7:36 pm-11:00 am

2 stops25h 24m

Incheon Intl

Thu 10/30

11:40 am-1:52 pm

2 stops40h 12m

$1,298

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/31

Showing 1-10 of 60 results

...

Best time to book a flight from Illinois to South Korea

Have a flexible travel schedule? Discover the best time to fly to South Korea from Illinois 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.

Cheapflights Insights

Everything you need to know about your flight from Illinois to South Korea

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

Currently, February is the cheapest month in which you can book a flight from Illinois to South Korea (average of $1,002). Flying from Illinois to South Korea in June is currently the most expensive (average of $1,661). 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 IL to KR?

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

Weekly flight availability from Illinois to South Korea

The most flights from USIL to KR0 are scheduled on a Monday (2 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (1 on average).

Rainfall in South Korea by month

In terms of precipitation, rainfall in South Korea ranges from 0.8 - 10.2 inches per month. July is typically the wettest month, when rainfall can reach 10.2 in. January is typically the driest time to visit South Korea when rainfall is around 0.8 in.

Temperature in South Korea by month

If weather is an important factor for your trip to South Korea, use this chart to help with planning. For those seeking warmer temperatures, August is the ideal time of year to visit, when temperatures reach an average of 77.0 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 28.4 F).

Reviews of airlines servicing South Korea

Peruse reviews from past customers who have flown with EVA Air, Korean Air and Japan Airlines from Illinois to South Korea to help guide your decision. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.

EVA Air

8.4

Very good

1,170 reviews

Reviews

1 / 20

6.0

Good

Anonymous,Feb 2025

SFO - TPE

Inside plane was clean and chair was comfortable, but flight attendants serving coffee without giving me cream and sugar, even I ask he escape my request.

EVA Air

8.4

Very good

1,170 reviews

EVA Air

8.4

Very good

1,170 reviews

Reviews

1 / 20

6.0

Good

Anonymous,Feb 2025

SFO - TPE

Inside plane was clean and chair was comfortable, but flight attendants serving coffee without giving me cream and sugar, even I ask he escape my request.

Korean Air

8.4

Very good

1,051 reviews

EVA Air

8.4

Very good

1,170 reviews

Reviews

1 / 20

6.0

Good

Anonymous,Feb 2025

SFO - TPE

Inside plane was clean and chair was comfortable, but flight attendants serving coffee without giving me cream and sugar, even I ask he escape my request.

Japan Airlines

8.3

Very good

1,440 reviews

EVA Air

8.4

Very good

1,170 reviews

Reviews

1 / 20

6.0

Good

Anonymous,Feb 2025

SFO - TPE

Inside plane was clean and chair was comfortable, but flight attendants serving coffee without giving me cream and sugar, even I ask he escape my request.

ANA

8.3

Very good

831 reviews

EVA Air

8.4

Very good

1,170 reviews

Reviews

1 / 20

6.0

Good

Anonymous,Feb 2025

SFO - TPE

Inside plane was clean and chair was comfortable, but flight attendants serving coffee without giving me cream and sugar, even I ask he escape my request.

Delta

8.0

Very good

7,899 reviews

EVA Air

8.4

Very good

1,170 reviews

Reviews

1 / 20

6.0

Good

Anonymous,Feb 2025

SFO - TPE

Inside plane was clean and chair was comfortable, but flight attendants serving coffee without giving me cream and sugar, even I ask he escape my request.

Related info for your journey

What are the cheapest airlines to fly from Illinois to South Korea one-way?
$537 is the cheapest one-way deal found within the past few days, from Turkish Airlines. You may also be able to find cheap deals on Cathay Pacific and Air Canada, with prices starting from $553 and $582, respectively.
Can I find deals for flights from Illinois to South Korea that include hotel bookings?
Yes. In addition to deals on Illinois to South Korea flights, Cheapflights offers vacation packages that include both flights and hotel.
How can I find direct flights from Illinois to South Korea?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Illinois to South Korea.
Can I find deals for business class flights from Illinois to South Korea?
Yes. Cheapflights offers flight deals from Illinois to South Korea by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.
What is the cheapest month to book a flight from Illinois to South Korea?
Currently, February is the cheapest month in which you can book a flight from Illinois to South Korea (average of $1,002). Flying from Illinois to South Korea in June is currently the most expensive (average of $1,661). 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.

See more FAQs

Browse thousands of different options on Cheapflights for your next trip

Top 10 airlines flying from Illinois to South Korea

Airline	Cheapest	Average	Flexibility	On-time
United Airlines	Cheapest$803	Average$1,025	FlexibilityNo cancel fee	On-time69%
Turkish Airlines	Cheapest$848	Average$1,051	FlexibilityNo cancel fee	On-time77%
Cathay Pacific	Cheapest$873	Average$1,000	FlexibilityNo cancel fee	On-time72%
Air Canada	Cheapest$891	Average$1,314	FlexibilityNo cancel fee	On-time67%
American Airlines	Cheapest$895	Average$1,229	FlexibilityNo cancel fee	On-time71%
EVA Air	Cheapest$1,059	Average$1,246	FlexibilityNo cancel fee	On-time74%
Finnair	Cheapest$1,110	Average$1,503	FlexibilityNo cancel fee	On-time76%
Delta	Cheapest$1,156	Average$1,827	FlexibilityNo cancel fee	On-timeN/A
Asiana Airlines	Cheapest$1,271	Average$1,728	FlexibilityNo cancel fee	On-time76%
Korean Air	Cheapest$1,522	Average$2,048	FlexibilityNo cancel fee	On-time81%

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$471+ Cheap flights from Illinois to South Korea

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 5/12. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Illinois to South Korea with Cheapflights

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Cheap flight deals from Illinois to South Korea

Keep the following information in mind while searching for Illinois to South Korea flight deals. Data was last updated March 31, 2025.

Most accurate provider

Most trusted provider

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Good round-trip deal

Good one-way deal

Find flight deals from Illinois to South Korea

Cheapest flights from Illinois to South KoreaExplore the most affordable flight options available from Illinois to South Korea. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 31, 2025.

Explore the most affordable flight options available from Illinois to South Korea. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 31, 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from Illinois to South Korea that are best for you.

Best time to book a flight from Illinois to South Korea

Have a flexible travel schedule? Discover the best time to fly to South Korea from Illinois with our price prediction graph.

Cheapflights Insights

Everything you need to know about your flight from Illinois to South Korea

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

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

Find hourly flight availability from Illinois to South Korea. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated March 31, 2025.

Weekly flight availability from Illinois to South Korea

Explore weekly flight availability from Illinois to South Korea. 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 March 31, 2025.

Rainfall in South Korea by month

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

Temperature in South Korea by month

Plan your trip to South Korea by taking into account the average temperature totals by month.

Reviews of airlines servicing South Korea

Peruse reviews from past customers who have flown with EVA Air, Korean Air and Japan Airlines from Illinois to South Korea to help guide your decision. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

Find useful and relevant information for your journey from Illinois to South Korea. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

What are the cheapest airlines to fly from Illinois to South Korea one-way?

Can I find deals for flights from Illinois to South Korea that include hotel bookings?

How can I find direct flights from Illinois to South Korea?

Can I find deals for business class flights from Illinois to South Korea?

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

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Illinois to South Korea

See prices for flight routes from nearby airports that may be better suited for you.

Top 10 airlines flying from Illinois to South Korea

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Cheapest flights from Illinois to South Korea
Explore the most affordable flight options available from Illinois to South Korea. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 31, 2025.