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Sofia

$324+ 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 10/4. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — SOF
Oct 17 — Oct 241
Fri 10/17
Fri 10/24
1 adult, Economy
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Cheap flight deals from Illinois to Sofia

Keep the following information in mind while searching for Illinois to Sofia flight deals. Data was last updated September 17, 2025.

Round-trip from

$548
(British Airways)

One-way from

$324
(Kiwi.com)

Popular in

June

Cheapest in

February

Average price

$595
From Illinois to Sofia
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One-way flight from Illinois to Sofia
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Highest demand for flights based on searches. 27% potential increase in price ($270 potential increase over avg. RT price).
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Cheapest flight prices on average. 5% potential price decrease ($38 potential savings vs. average RT price).
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Average for round-trip flights in September 2025
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Find 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 September 17, 2025.

This Ticket deal was found by Cheapflights users on 9/17. 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 Ticket is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/193:30 pmSTL - SOF
1 stop13h 30mLufthansa
Wed 10/296:10 amSOF - STL
2 stops18h 29mLufthansa
Deal found 9/17$551
This United Airlines deal was found by Cheapflights users on 9/15. 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 11/249:50 pmORD - SOF
1 stop12h 30mUnited Airlines
Wed 3/116:10 amSOF - ORD
2 stops19h 17mUnited Airlines
Deal found 9/15$551
This oojo deal was found by Cheapflights users on 9/17. 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.
Sun 11/99:55 pmORD - SOF
2 stops35h 55mLOT
Sun 11/236:35 pmSOF - ORD
2 stops33h 20mLOT
Deal found 9/17$553
This Booking.com deal was found by Cheapflights users on 9/17. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/89:40 pmORD - SOF
1 stop12h 15mLOT
Wed 10/225:20 amSOF - ORD
1 stop22h 20mLOT
Deal found 9/17$554
This FlightHub deal was found by Cheapflights users on 9/15. 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 11/1611:50 amORD - SOF
1 stop19h 20mTurkish Airlines
Sun 11/304:00 pmSOF - ORD
1 stop26h 05mTurkish Airlines
Deal found 9/15$555
This United Airlines deal was found by Cheapflights users on 9/15. 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 10/136:00 pmORD - SOF
1 stop21h 00mUnited Airlines
Wed 11/56:10 amSOF - ORD
2 stops35h 55mUnited Airlines
Deal found 9/15$557
This Air Canada deal was found by Cheapflights users on 9/15. 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.
Sun 11/1612:50 pmORD - SOF
2 stops16h 20mAir Canada
Fri 3/66:10 amSOF - ORD
2 stops21h 20mAir Canada
Deal found 9/15$558
This FlightHub deal was found by Cheapflights users on 9/15. 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 12/2810:35 pmORD - SOF
1 stop16h 10mMultiple Airlines
Mon 3/23:00 pmSOF - ORD
1 stop33h 20mMultiple Airlines
Deal found 9/15$559
This United Airlines deal was found by Cheapflights users on 9/15. 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 10/292:22 pmORD - SOF
2 stops16h 28mUnited Airlines
Fri 11/72:35 pmSOF - ORD
1 stop13h 30mUnited Airlines
Deal found 9/15$560
This FlightHub deal was found by Cheapflights users on 9/14. 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.
Fri 10/174:55 pmORD - SOF
1 stop12h 55mLOT
Tue 10/282:35 pmSOF - ORD
1 stop13h 25mLOT
Deal found 9/14$561
This FlightHub deal was found by Cheapflights users on 9/17. 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 10/79:40 pmORD - SOF
1 stop32h 10mLOT
Sun 10/126:40 pmSOF - ORD
1 stop33h 00mLOT
Deal found 9/17$562
This United deal was found by Cheapflights users on 9/16. 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 is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/206:30 amORD - SOF
2 stops20h 45mMultiple Airlines
Tue 11/46:00 amSOF - ORD
2 stops24h 05mMultiple Airlines
Deal found 9/16$563

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 September 17, 2025.
Use the filters below to find and compare flights from Illinois to Sofia that are best for you.

Fly from

Illinois

Fly to

Sofia

Route

Depart

Return

Price

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Sun 10/19

3:30 pm-1:00 pm

1 stop13h 30m

Sofia

Wed 10/29

6:10 am-5:39 pm

2 stops18h 29m

$551

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Mon 10/20

3:35 pm-12:00 pm

1 stop12h 25m

Sofia

Tue 11/4

6:00 am-1:10 pm

1 stop15h 10m

$551

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Tue 1/13

9:50 pm-6:20 pm

1 stop12h 30m

Sofia

Tue 1/27

6:00 am-8:00 pm

2 stops22h 00m

$552

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Sun 1/11

9:50 pm-6:20 pm

1 stop12h 30m

Sofia

Thu 4/2

6:15 am-2:45 pm

1 stop16h 30m

$552

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Tue 1/13

9:50 pm-6:20 pm

1 stop12h 30m

Sofia

Tue 1/27

6:00 am-6:51 pm

2 stops20h 51m

$552

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Sun 11/9

9:55 pm-5:50 pm

2 stops35h 55m

Sofia

Sun 11/23

6:35 pm-7:55 pm

2 stops33h 20m

$553

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Mon 11/24

12:50 pm-1:25 pm

2 stops16h 35m

Sofia

Wed 3/11

6:10 am-6:27 pm

2 stops19h 17m

$555

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Tue 1/13

10:35 am-1:45 pm

2 stops19h 10m

Sofia

Wed 4/1

6:15 am-2:45 pm

1 stop16h 30m

$556

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Tue 2/17

5:50 pm-6:20 pm

2 stops16h 30m

Sofia

Tue 3/3

6:00 am-2:55 pm

2 stops16h 55m

$556

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Mon 10/13

6:00 pm-11:00 pm

1 stop21h 00m

Sofia

Wed 11/5

6:10 am-7:30 pm

2 stops21h 20m

$557

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/16

Showing 1-10 of 41 results
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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 $632). 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.

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

Find hourly flight availability from Illinois to Sofia. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated September 17, 2025.

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

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 12h 25m. Lufthansa provides one of the quickest options available for as low as $551. 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 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 $632). 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

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Alternative routes for Illinois to Sofia

See prices for flight routes from nearby airports that may be better suited for you.
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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 September 17, 2025.
AirlineCheapestAverageFlexibilityOn-time
Turkish AirlinesCheapest$497Average$698FlexibilityNo cancel feeOn-time77%
Air FranceCheapest$498Average$624FlexibilityNo cancel feeOn-time77%
KLMCheapest$533Average$739FlexibilityNo cancel feeOn-time75%
LOTCheapest$569Average$905FlexibilityNo cancel feeOn-time81%
LufthansaCheapest$589Average$894FlexibilityNo cancel feeOn-time76%
SWISSCheapest$596Average$813FlexibilityNo cancel feeOn-time79%
United AirlinesCheapest$601Average$791FlexibilityNo cancel feeOn-time69%
British AirwaysCheapest$613Average$808FlexibilityNo cancel feeOn-time70%
Austrian AirlinesCheapest$613Average$997FlexibilityNo cancel feeOn-time78%
Air SerbiaCheapest$652Average$1,021FlexibilityNo cancel feeOn-timeN/A

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