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Sofia

$296+ 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 4/22. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — SOF
Apr 9 — Apr 161
Thu 4/9
Thu 4/16
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 March 10, 2026.

This FlightHub deal was found by Cheapflights users on 3/7. 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 4/158:10 pm
ORD
-
SOF
1 stop33h 05m
Turkish Airlines
Wed 4/299:05 pm
SOF
-
ORD
1 stop20h 35m
Turkish Airlines
Deal found 3/7$560
This oojo deal was found by Cheapflights users on 3/6. 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.
Mon 5/411:25 am
ORD
-
SOF
1 stop13h 20m
Turkish Airlines
Thu 5/149:35 am
SOF
-
ORD
1 stop32h 05m
Turkish Airlines
Deal found 3/6$565
This FlightHub deal was found by Cheapflights users on 3/6. 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 9/68:10 pm
ORD
-
SOF
1 stop16h 05m
Turkish Airlines
Tue 9/229:05 pm
SOF
-
ORD
1 stop20h 35m
Turkish Airlines
Deal found 3/6$567
This FlightHub deal was found by Cheapflights users on 3/6. 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 8/2411:25 am
ORD
-
SOF
1 stop13h 20m
Turkish Airlines
Fri 9/182:05 pm
SOF
-
ORD
1 stop27h 35m
Turkish Airlines
Deal found 3/6$569
This oojo deal was found by Cheapflights users on 3/6. 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.
Tue 4/78:10 pm
ORD
-
SOF
1 stop16h 05m
Turkish Airlines
Tue 4/219:05 pm
SOF
-
ORD
1 stop20h 35m
Turkish Airlines
Deal found 3/6$574
This oojo deal was found by Cheapflights users on 3/9. 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 4/238:10 pm
ORD
-
SOF
1 stop28h 35m
Turkish Airlines
Thu 4/309:35 am
SOF
-
ORD
1 stop32h 05m
Turkish Airlines
Deal found 3/9$575
This oojo deal was found by Cheapflights users on 3/6. 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.
Sat 5/28:10 pm
ORD
-
SOF
1 stop28h 35m
Turkish Airlines
Tue 5/129:35 am
SOF
-
ORD
1 stop32h 05m
Turkish Airlines
Deal found 3/6$578
This Kiwi.com deal was found by Cheapflights users on 3/9. 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 11/145:30 pm
ORD
-
SOF
1 stop14h 00m
Air Serbia
Fri 11/275:00 am
SOF
-
ORD
1 stop17h 40m
Air Serbia
Deal found 3/9$585
This oojo deal was found by Cheapflights users on 3/5. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/68:10 pm
ORD
-
SOF
1 stop34h 50m
Turkish Airlines
Mon 4/209:05 pm
SOF
-
ORD
1 stop20h 35m
Turkish Airlines
Deal found 3/5$587
This Kiwi.com deal was found by Cheapflights users on 3/6. 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.
Fri 5/19:50 pm
ORD
-
SOF
1 stop32h 00m
LOT
Mon 5/116:45 pm
SOF
-
ORD
1 stop28h 25m
LOT
Deal found 3/6$591
This United Airlines deal was found by Cheapflights users on 3/8. 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.
Wed 4/228:30 am
STL
-
SOF
2 stops19h 40m
United Airlines
Wed 4/296:20 am
SOF
-
STL
1 stop15h 05m
United Airlines
Deal found 3/8$654
This Air France deal was found by Cheapflights users on 3/8. 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 France is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/2211:42 am
STL
-
SOF
2 stops18h 18m
Multiple Airlines
Wed 4/297:00 am
SOF
-
STL
2 stops21h 44m
Multiple Airlines
Deal found 3/8$661

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 March 10, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$560
(FlightHub)

One-way from

$296
(Kiwi.com)

Popular in

June

Cheapest in

February

Average price

$626
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. 25% potential increase in price ($254 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 March 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 March 10, 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
Quickest round-trip

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Wed 4/22

3:30 pm-1:25 pm

1 stop13h 55m

Sofia

Wed 4/29

6:20 am-1:25 pm

1 stop15h 05m

$704

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Sun 4/19

9:10 am-11:00 pm

2 stops29h 50m

Sofia

Sun 4/26

1:50 pm-3:25 pm

2 stops33h 35m

$712

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Fri 4/10

8:15 pm-10:30 pm

2 stops18h 15m

Sofia

Fri 5/1

6:20 am-1:25 pm

1 stop15h 05m

$716

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Sun 4/19

3:30 pm-1:35 pm

1 stop14h 05m

Sofia

Sun 4/26

6:20 am-1:25 pm

1 stop15h 05m

$759

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Mon 8/3

3:35 pm-12:10 pm

1 stop12h 35m

Sofia

Tue 8/25

6:10 am-6:37 pm

2 stops20h 27m

$761

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Fri 4/10

9:10 am-1:15 pm

2 stops20h 05m

Sofia

Sat 5/2

1:55 pm-11:19 pm

2 stops17h 24m

$776

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Sat 9/5

8:40 pm-12:10 pm

2 stops31h 30m

Sofia

Sat 9/26

6:20 am-7:55 pm

1 stop21h 35m

$780

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Sat 4/11

8:03 pm-7:20 pm

2 stops39h 17m

Sofia

Wed 6/17

9:25 pm-11:59 pm

2 stops34h 34m

$781

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Tue 5/12

6:15 pm-6:40 pm

2 stops16h 25m

Sofia

Sun 5/31

6:10 am-11:26 pm

2 stops25h 16m

$788

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Sun 5/17

5:55 pm-11:00 pm

1 stop21h 05m

Sofia

Wed 6/17

6:20 am-2:55 pm

1 stop16h 35m

$792

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/6

Showing 1-10 of 44 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, November is the cheapest month in which you can book a flight from Illinois to Sofia (average of $472). Flying from Illinois to Sofia in June is currently the most expensive (average of $825). 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?

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 13h 55m. Lufthansa provides one of the quickest options available for as low as $704. There are 5444 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 Austrian Airlines ($330).

  • 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, November is the cheapest month in which you can book a flight from Illinois to Sofia (average of $472). Flying from Illinois to Sofia in June is currently the most expensive (average of $825). 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 March 10, 2026.
AirlineCheapestAverageFlexibilityOn-time
ITA AirwaysCheapest$469Average$991FlexibilityNo cancel feeOn-time81%
Turkish AirlinesCheapest$521Average$743FlexibilityNo cancel feeOn-time77%
KLMCheapest$533Average$652FlexibilityNo cancel feeOn-time75%
SWISSCheapest$565Average$760FlexibilityNo cancel feeOn-time79%
United AirlinesCheapest$566Average$791FlexibilityNo cancel feeOn-time69%
LOTCheapest$583Average$869FlexibilityNo cancel feeOn-time81%
Air FranceCheapest$585Average$624FlexibilityNo cancel feeOn-time77%
LufthansaCheapest$586Average$874FlexibilityNo cancel feeOn-time76%
Austrian AirlinesCheapest$587Average$848FlexibilityNo cancel feeOn-time78%
British AirwaysCheapest$609Average$749FlexibilityNo cancel feeOn-time70%

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