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Sofia

$310+ Cheap flights from Illinois to Sofia (SOF)

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 8/31. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — SOF
Sep 1 — Sep 81
Tue 9/1
Tue 9/8
1 adult, Economy
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Cheap flight deals from Illinois to Sofia

Cheapest flights from Illinois to Sofia
Explore the most affordable flight options available from Illinois to Sofia. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 2, 2026.

This Kiwi.com deal was found by Cheapflights users on 7/28. 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.
Thu 9/248:10 pm
ORD
-
SOF
1 stop28h 35m
Turkish Airlines
Sun 10/49:10 pm
SOF
-
ORD
1 stop20h 30m
Turkish Airlines
Deal found 7/28$767
This oojo deal was found by Cheapflights users on 7/30. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/39:50 pm
ORD
-
SOF
1 stop32h 05m
LOT
Thu 9/246:45 pm
SOF
-
ORD
1 stop33h 05m
LOT
Deal found 7/30$768
This CheapOair deal was found by Cheapflights users on 7/28. 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 8/1911:25 am
ORD
-
SOF
1 stop13h 20m
Turkish Airlines
Sat 10/109:35 am
SOF
-
ORD
1 stop32h 05m
Turkish Airlines
Deal found 7/28$769
This FlightHub deal was found by Cheapflights users on 7/28. 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.
Sun 8/238:10 pm
ORD
-
SOF
1 stop28h 35m
Turkish Airlines
Thu 9/243:50 pm
SOF
-
ORD
1 stop25h 50m
Turkish Airlines
Deal found 7/28$770
This Expedia deal was found by Cheapflights users on 7/30. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/78:50 pm
ORD
-
SOF
2 stops32h 35m
Multiple Airlines
Sun 11/226:00 am
SOF
-
ORD
1 stop20h 25m
Multiple Airlines
Deal found 7/30$771
This Expedia deal was found by Cheapflights users on 7/29. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/278:45 am
ORD
-
SOF
2 stops20h 40m
Multiple Airlines
Fri 12/116:25 am
SOF
-
ORD
2 stops16h 27m
Multiple Airlines
Deal found 7/29$772
This United Airlines deal was found by Cheapflights users on 7/30. 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 12/39:50 pm
ORD
-
SOF
1 stop17h 05m
United Airlines
Fri 12/252:10 pm
SOF
-
ORD
1 stop13h 55m
United Airlines
Deal found 7/30$773
This Justfly.com deal was found by Cheapflights users on 8/1. 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 Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/411:25 am
ORD
-
SOF
1 stop19h 35m
Turkish Airlines
Thu 2/259:40 am
SOF
-
ORD
1 stop16h 40m
Turkish Airlines
Deal found 8/1$774
This FlightHub deal was found by Cheapflights users on 8/1. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/128:10 pm
ORD
-
SOF
1 stop28h 35m
Turkish Airlines
Mon 10/193:50 pm
SOF
-
ORD
1 stop25h 50m
Turkish Airlines
Deal found 8/1$775
This FlightHub deal was found by Cheapflights users on 8/1. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/208:10 pm
ORD
-
SOF
1 stop28h 35m
Turkish Airlines
Sat 10/173:50 pm
SOF
-
ORD
1 stop25h 50m
Turkish Airlines
Deal found 8/1$776
This United Airlines deal was found by Cheapflights users on 7/30. 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.
Sun 12/69:50 pm
ORD
-
SOF
1 stop17h 05m
United Airlines
Tue 12/296:25 am
SOF
-
ORD
1 stop14h 45m
United Airlines
Deal found 7/30$777
This Mytrip deal was found by Cheapflights users on 7/31. 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.
Sun 9/2011:25 am
ORD
-
SOF
2 stops19h 45m
Multiple Airlines
Wed 9/303:55 pm
SOF
-
ORD
2 stops25h 45m
Multiple Airlines
Deal found 7/31$778

Find flight deals from Illinois to Sofia

Keep the following information in mind while searching for Illinois to Sofia flight deals. Data was last updated August 2, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$767
(Kiwi.com)

One-way from

$310
(Kiwi.com)

Popular in

July

Cheapest in

February

Average price

$773
Provider with most accurate pricing for Chicago (CHI)-Sofia flight deals.
Search Deals
Provider most trusted by Cheapflights users for Chicago (CHI)-Sofia flights.
Search Deals
From Illinois to Sofia
Search Deals
One-way flight from Illinois to Sofia
Search Deals
Highest demand for flights based on searches. 24% potential increase in price ($252 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease ($35 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in August 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Illinois to Sofia 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 August 2, 2026.
Use the filters below to find and compare flights from Illinois to Sofia that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Sat 9/26

11:25 am-12:15 pm

1 stop16h 50m

Sofia

Sat 10/31

4:00 pm-12:00 pm

1 stop27h 00m

$799

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Fri 9/11

8:10 pm-12:15 pm

1 stop32h 05m

Sofia

Fri 9/25

9:10 pm-9:40 am

1 stop20h 30m

$810

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Wed 9/23

8:10 pm-8:45 am

1 stop28h 35m

Sofia

Fri 11/20

9:40 am-10:00 am

1 stop32h 20m

$825

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Sun 9/27

5:00 pm-7:20 pm

1 stop18h 20m

Sofia

Mon 11/23

5:15 pm-6:45 pm

1 stop33h 30m

$837

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Wed 9/23

7:05 pm-1:25 pm

1 stop34h 20m

Sofia

Mon 11/23

5:15 pm-6:45 pm

1 stop33h 30m

$837

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Sun 10/4

9:40 pm-6:40 pm

1 stop13h 00m

Sofia

Fri 2/26

6:25 am-2:52 pm

2 stops16h 27m

$838

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Mon 9/14

10:50 am-12:10 pm

2 stops17h 20m

Sofia

Wed 9/23

6:20 am-12:55 pm

1 stop14h 35m

$839

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Wed 9/2

1:55 pm-6:40 pm

2 stops20h 45m

Sofia

Wed 9/16

6:20 am-4:29 pm

2 stops18h 09m

$850

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Sat 9/12

8:10 pm-8:20 pm

1 stop16h 10m

Sofia

Sun 9/20

3:50 pm-9:40 am

1 stop25h 50m

$864

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Sat 9/26

11:25 am-12:15 pm

1 stop16h 50m

Sofia

Fri 11/20

9:40 am-10:00 am

1 stop32h 20m

$865

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/28

Showing 1-10 of 38 resultsSorted by cheapest first
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Best time to book a flight from Illinois to Sofia

Have a flexible travel schedule? Discover the best time to fly to Sofia 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 Sofia

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

Currently, February is the cheapest month in which you can book a flight from Illinois to Sofia (average of $593). Flying from Illinois to Sofia in June is currently the most expensive (average of $1,154). 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.

How much does it cost to fly round-trip from Illinois to Sofia?

Airfare is typical for this route at the moment.
Illinois to Sofia flights typically cost between $685 and $900 in September.
The cheapest round-trip price found within the last 5 days was $767 on Turkish Airlines (Sep 24-Oct 4).

How far ahead should I book a flight from Illinois to Sofia?

Booking 41 days in advance of your planned departure date is, on average, the best time to get cheap flights from Illinois to Sofia. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

Related info for your journey

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

  • What airport do you fly into for flights to Sofia from Illinois?

    Most people fly into Sofia (SOF) if they book a flight to Sofia from Illinois. Sofia is conveniently located just 4.2 mi from Sofia’s city center.

  • How long is the flight from Illinois to Sofia?

    A quick flight from Illinois to Sofia can take about 16h 50m. Turkish Airlines provides one of the quickest options available for as low as $799. There are 5194 mi between Illinois and Sofia. Both multi-stop and nonstop flights can be found to your destination and back.

  • What are the cheapest airlines to fly from Illinois to Sofia one-way?

    The cheapest airlines for a one-way flight from Illinois to Sofia are JetBlue ($275), Turkish Airlines ($295), and SWISS ($344).

  • What are the most popular routes from Illinois to Sofia?

    While some choose either Lambert-St Louis - Sofia or Chicago Midway - Sofia, Chicago O'Hare Intl - Sofia is the most popular route from Illinois to Sofia.

  • Can I find deals for flights from Illinois to Sofia that include hotel bookings?

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

  • How can I find direct flights from Illinois to Sofia?

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

  • Can I find deals for business class flights from Illinois to Sofia?

    Yes. Cheapflights offers flight deals from Illinois to Sofia 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 Sofia?

    Currently, February is the cheapest month in which you can book a flight from Illinois to Sofia (average of $593). Flying from Illinois to Sofia in June is currently the most expensive (average of $1,154). 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

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

Top 10 airlines flying from Illinois to Sofia

Discover the top 10 airlines that operate flights from Illinois to Sofia. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated August 2, 2026.
AirlineCheapestAverageFlexibilityOn-time
Turkish AirlinesCheapest$523Average$697FlexibilityNo cancel feeOn-time77%
LOTCheapest$579Average$982FlexibilityNo cancel feeOn-time81%
United AirlinesCheapest$583Average$1,018FlexibilityNo cancel feeOn-time69%
Air FranceCheapest$585Average$870FlexibilityNo cancel feeOn-time77%
SWISSCheapest$594Average$837FlexibilityNo cancel feeOn-time79%
LufthansaCheapest$608Average$943FlexibilityNo cancel feeOn-time76%
British AirwaysCheapest$609Average$649FlexibilityNo cancel feeOn-time70%
KLMCheapest$614Average$814FlexibilityNo cancel feeOn-time75%
Austrian AirlinesCheapest$701Average$941FlexibilityNo cancel feeOn-time78%
Air SerbiaCheapest$703Average$869FlexibilityNo cancel feeOn-timeN/A

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