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Sofia

$292+ 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 12/9. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — SOF
Dec 20 — Dec 271
Sat 12/20
Sat 12/27
1 adult, Economy
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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 November 20, 2025.

This CrystalTravel deal was found by Cheapflights users on 11/20. 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 CrystalTravel is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/29:55 pmORD - SOF
1 stop11h 55mLOT
Wed 12/102:35 pmSOF - ORD
1 stop13h 25mLOT
Deal found 11/20$570
This CrystalTravel deal was found by Cheapflights users on 11/19. 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 CrystalTravel is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/99:50 pmORD - SOF
1 stop16h 55mLufthansa
Tue 12/236:05 amSOF - ORD
1 stop20h 20mLufthansa
Deal found 11/19$576
This FlightHub deal was found by Cheapflights users on 11/19. 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.
Thu 12/49:55 pmORD - SOF
1 stop11h 55mLOT
Fri 12/126:35 pmSOF - ORD
1 stop33h 25mLOT
Deal found 11/19$588
This Cheapflightsfares deal was found by Cheapflights users on 11/19. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/289:50 pmORD - SOF
1 stop16h 55mLufthansa
Mon 3/22:20 pmSOF - ORD
1 stop13h 45mLufthansa
Deal found 11/19$595
This Cheapflightsfares deal was found by Cheapflights users on 11/20. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/266:00 pmORD - SOF
1 stop11h 15mLufthansa
Fri 12/56:05 amSOF - ORD
1 stop20h 20mLufthansa
Deal found 11/20$597
This Mytrip deal was found by Cheapflights users on 11/20. 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.
Tue 12/212:50 pmORD - SOF
2 stops16h 55mMultiple Airlines
Wed 12/106:10 amSOF - ORD
1 stop21h 55mMultiple Airlines
Deal found 11/20$602
This LOT deal was found by Cheapflights users on 11/20. 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 LOT is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/49:55 pmORD - SOF
1 stop31h 55mLOT
Sat 12/132:35 pmSOF - ORD
1 stop13h 25mLOT
Deal found 11/20$605
This United Airlines deal was found by Cheapflights users on 11/19. 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 12/19:50 pmORD - SOF
1 stop16h 55mUnited Airlines
Tue 12/166:00 amSOF - ORD
1 stop17h 20mUnited Airlines
Deal found 11/19$607
This Justfly.com deal was found by Cheapflights users on 11/20. 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.
Tue 12/212:50 pmORD - SOF
2 stops16h 55mAir Canada
Wed 12/102:00 pmSOF - ORD
2 stops29h 18mAir Canada
Deal found 11/20$611
This United Airlines deal was found by Cheapflights users on 11/19. 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 12/46:15 pmORD - SOF
2 stops20h 30mUnited Airlines
Tue 12/166:00 amSOF - ORD
1 stop15h 10mUnited Airlines
Deal found 11/19$612
This United Airlines deal was found by Cheapflights users on 11/19. 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 12/49:50 pmORD - SOF
1 stop16h 55mUnited Airlines
Sat 12/132:25 pmSOF - ORD
2 stops17h 18mUnited Airlines
Deal found 11/19$614
This Air France deal was found by Cheapflights users on 11/18. 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.
Sat 12/131:50 pmMDW - SOF
2 stops16h 05mMultiple Airlines
Tue 1/137:00 amSOF - MDW
2 stops19h 32mMultiple Airlines
Deal found 11/18$854

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 November 20, 2025.

Most accurate provider

Gotogate
3 stars

Most trusted provider

Gotogate
3 stars

Round-trip from

$543
(Lufthansa)

One-way from

$292
(Kiwi.com)

Popular in

June

Cheapest in

February

Average price

$641
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. 5% potential price decrease ($37 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in November 2025
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 November 20, 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

Wed 1/28

12:44 pm-1:15 pm

2 stops16h 31m

Sofia

Sun 2/1

6:10 am-10:58 pm

2 stops24h 48m

$543

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Mon 5/11

8:10 pm-8:15 pm

1 stop16h 05m

Sofia

Thu 5/28

9:35 am-6:15 pm

1 stop16h 40m

$575

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Thu 1/1

9:50 pm-10:45 pm

1 stop16h 55m

Sofia

Fri 1/16

6:05 am-1:10 pm

2 stops15h 05m

$575

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Sun 12/28

9:50 pm-10:45 pm

1 stop16h 55m

Sofia

Mon 3/2

2:20 pm-8:05 pm

1 stop13h 45m

$595

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Wed 1/14

3:35 pm-1:15 pm

2 stops13h 40m

Sofia

Thu 2/19

6:05 am-7:30 pm

2 stops21h 25m

$603

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Mon 1/12

6:00 pm-10:45 pm

1 stop20h 45m

Sofia

Mon 2/2

6:10 am-3:20 pm

1 stop17h 10m

$609

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Wed 4/8

7:10 am-6:40 pm

2 stops27h 30m

Sofia

Sun 4/12

6:10 am-7:55 pm

1 stop21h 45m

$609

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Wed 2/18

9:50 pm-6:20 pm

1 stop12h 30m

Sofia

Wed 3/4

6:10 am-2:55 pm

2 stops16h 45m

$609

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Mon 1/12

6:00 pm-1:15 pm

1 stop11h 15m

Sofia

Sun 2/1

6:10 am-3:20 pm

1 stop17h 10m

$609

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Thu 1/8

9:50 pm-10:45 pm

1 stop16h 55m

Sofia

Sat 1/31

6:25 am-3:20 pm

1 stop16h 55m

$609

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/20

Showing 1-10 of 38 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 $492). Flying from Illinois to Sofia in June is currently the most expensive (average of $826). 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 November 20, 2025.

A simple way to save on the total cost of your ticket is to fly from Illinois to Sofia in the evening. If you’re flexible enough to do this you can expect to save up to 35% on your trip compared to booking a flight in the morning.

What is the cheapest day to fly from Illinois to Sofia?

Use this chart to determine the cheapest time to fly round-trip from Illinois to Sofia. Price data was last updated on December 16, 2024.

Travelers seeking maximum savings on their Illinois to Sofia flight should consider departing on Tuesday mornings when fares are most often at their lowest. Sunday at noon flights should be avoided if possible as fares are typically the most expensive at this time.

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 05m. Lufthansa provides one of the quickest options available for as low as $575. 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 $492). Flying from Illinois to Sofia in June is currently the most expensive (average of $826). 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

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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 November 20, 2025.
AirlineCheapestAverageFlexibilityOn-time
Turkish AirlinesCheapest$511Average$770FlexibilityNo cancel feeOn-time77%
KLMCheapest$533Average$696FlexibilityNo cancel feeOn-time75%
LOTCheapest$570Average$967FlexibilityNo cancel feeOn-time81%
Air FranceCheapest$585Average$624FlexibilityNo cancel feeOn-time77%
LufthansaCheapest$590Average$883FlexibilityNo cancel feeOn-time76%
SWISSCheapest$593Average$808FlexibilityNo cancel feeOn-time79%
United AirlinesCheapest$600Average$791FlexibilityNo cancel feeOn-time69%
Austrian AirlinesCheapest$606Average$976FlexibilityNo cancel feeOn-time78%
British AirwaysCheapest$611Average$759FlexibilityNo cancel feeOn-time70%
Air SerbiaCheapest$634Average$1,010FlexibilityNo cancel feeOn-timeN/A

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