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Sofia

$264+ 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 9/2. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — SOF
Jul 31 — Aug 71
Fri 7/31
Fri 8/7
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 July 1, 2026.

This FlightHub deal was found by Cheapflights users on 6/30. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/33:40 pm
ORD
-
SOF
2 stops37h 25m
Multiple Airlines
Tue 8/1812:55 pm
SOF
-
ORD
2 stops32h 00m
Multiple Airlines
Deal found 6/30$835
This FlightHub deal was found by Cheapflights users on 7/1. 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 10/72:01 pm
ORD
-
SOF
2 stops20h 39m
Multiple Airlines
Sun 10/186:20 am
SOF
-
ORD
1 stop21h 35m
Multiple Airlines
Deal found 7/1$836
This Justfly.com deal was found by Cheapflights users on 6/30. 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 Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/199:40 pm
ORD
-
SOF
1 stop13h 00m
Multiple Airlines
Tue 9/156:10 am
SOF
-
ORD
2 stops16h 42m
Multiple Airlines
Deal found 6/30$837
This FlightHub deal was found by Cheapflights users on 6/30. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/197:11 am
ORD
-
SOF
2 stops27h 29m
Multiple Airlines
Thu 9/36:30 am
SOF
-
ORD
1 stop14h 25m
Multiple Airlines
Deal found 6/30$838
This FlightHub deal was found by Cheapflights users on 6/30. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/85:10 pm
ORD
-
SOF
1 stop16h 50m
LOT
Sat 8/226:45 pm
SOF
-
ORD
2 stops52h 25m
LOT
Deal found 6/30$839
This United Airlines deal was found by Cheapflights users on 6/26. 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.
Mon 7/274:05 pm
ORD
-
SOF
1 stop17h 55m
United Airlines
Thu 8/206:30 am
SOF
-
ORD
1 stop14h 25m
United Airlines
Deal found 6/26$840
This KLM deal was found by Cheapflights users on 6/29. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/2412:30 pm
MDW
-
SOF
2 stops18h 35m
KLM
Sun 11/87:00 am
SOF
-
MDW
2 stops17h 39m
KLM
Deal found 6/29$840
This Turkish Airlines deal was found by Cheapflights users on 6/26. 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 Turkish Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/611:25 am
ORD
-
SOF
1 stop19h 35m
Turkish Airlines
Sun 10/43:50 pm
SOF
-
ORD
1 stop34h 25m
Turkish Airlines
Deal found 6/26$841
This Air Canada deal was found by Cheapflights users on 6/30. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/283:45 pm
ORD
-
SOF
2 stops36h 25m
Air Canada
Tue 10/66:10 am
SOF
-
ORD
2 stops16h 42m
Air Canada
Deal found 6/30$842
This United Airlines deal was found by Cheapflights users on 6/30. 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.
Mon 8/179:50 am
ORD
-
SOF
2 stops18h 20m
United Airlines
Wed 9/166:20 am
SOF
-
ORD
1 stop16h 35m
United Airlines
Deal found 6/30$843
This CheapOair deal was found by Cheapflights users on 6/28. 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.
Mon 7/278:40 pm
ORD
-
SOF
2 stops31h 30m
Multiple Airlines
Wed 8/1211:05 am
SOF
-
ORD
1 stop33h 30m
Multiple Airlines
Deal found 6/28$844
This FlightHub deal was found by Cheapflights users on 7/1. 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 10/72:01 pm
ORD
-
SOF
2 stops20h 39m
Air Canada
Sun 10/186:10 am
SOF
-
ORD
2 stops21h 38m
Air Canada
Deal found 7/1$845

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 July 1, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$835
(FlightHub)

One-way from

$264
(Kiwi.com)

Popular in

June

Cheapest in

February

Average price

$954
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. 26% potential increase in price ($275 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 5% potential price decrease ($37 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in July 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 July 1, 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

MDW - SOF

MDWSOF

Chicago Midway

Sat 11/28

1:00 pm-2:05 pm

2 stops17h 05m

Sofia

Sun 12/13

7:00 am-4:50 pm

2 stops17h 50m

$840

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Sun 8/23

9:50 am-12:10 pm

2 stops18h 20m

Sofia

Thu 9/17

6:30 am-2:55 pm

1 stop16h 25m

$843

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Mon 8/17

9:50 am-12:10 pm

2 stops18h 20m

Sofia

Wed 9/16

6:20 am-2:55 pm

1 stop16h 35m

$843

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Wed 8/5

3:53 pm-6:40 pm

2 stops18h 47m

Sofia

Sun 8/23

12:55 pm-2:00 pm

1 stop33h 05m

$844

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Mon 8/3

2:20 pm-12:10 pm

2 stops13h 50m

Sofia

Tue 8/18

12:55 pm-12:55 pm

2 stops32h 00m

$845
Quickest round-trip

ChicagoSofia

MDW - SOF

MDWSOF

Chicago Midway

Mon 8/17

1:51 pm-2:00 pm

2 stops16h 09m

Sofia

Tue 10/6

7:00 am-4:25 pm

2 stops17h 25m

$846

ChicagoSofia

MDW - SOF

MDWSOF

Chicago Midway

Wed 8/19

1:25 pm-2:00 pm

2 stops16h 35m

Sofia

Thu 9/3

7:00 am-6:01 pm

2 stops19h 01m

$846

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Sun 9/6

9:40 pm-11:15 pm

1 stop17h 35m

Sofia

Tue 10/6

12:55 pm-10:29 pm

2 stops17h 34m

$846

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Mon 8/10

1:30 pm-12:10 pm

2 stops14h 40m

Sofia

Mon 8/31

7:25 pm-6:15 pm

1 stop30h 50m

$850

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Sun 8/9

6:00 pm-11:15 pm

1 stop21h 15m

Sofia

Sun 8/23

6:10 am-7:55 pm

2 stops21h 45m

$850

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/27

Showing 1-10 of 40 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, October is the cheapest month in which you can book a flight from Illinois to Sofia (average of $385). Flying from Illinois to Sofia in June is currently the most expensive (average of $1,183). 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?

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 17h 05m. KLM provides one of the quickest options available for as low as $840. There are 5198 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 Turkish Airlines ($295), United Airlines ($305), and Air Serbia ($353).

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

    While some choose either Chicago Midway - Sofia or Lambert-St Louis - 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, October is the cheapest month in which you can book a flight from Illinois to Sofia (average of $385). Flying from Illinois to Sofia in June is currently the most expensive (average of $1,183). 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

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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 July 1, 2026.
AirlineCheapestAverageFlexibilityOn-time
ITA AirwaysCheapest$508Average$1,179FlexibilityNo cancel feeOn-time81%
Turkish AirlinesCheapest$520Average$686FlexibilityNo cancel feeOn-time77%
SWISSCheapest$565Average$822FlexibilityNo cancel feeOn-time79%
United AirlinesCheapest$566Average$917FlexibilityNo cancel feeOn-time69%
Austrian AirlinesCheapest$575Average$908FlexibilityNo cancel feeOn-time78%
LOTCheapest$578Average$806FlexibilityNo cancel feeOn-time81%
Air FranceCheapest$585Average$870FlexibilityNo cancel feeOn-time77%
LufthansaCheapest$586Average$898FlexibilityNo cancel feeOn-time76%
British AirwaysCheapest$609Average$646FlexibilityNo cancel feeOn-time70%
KLMCheapest$614Average$814FlexibilityNo cancel feeOn-time75%

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