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Sofia

$301+ 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 12/30. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — SOF
ene. 11 — ene. 181
dom. 1/11
dom. 1/18
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 diciembre 12, 2025.

This Gotogate deal was found by Cheapflights users on 12/9. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 12/3110:00 amORD - SOF
2 stops19h 50mMultiple Airlines
mié. 1/146:05 amSOF - ORD
1 stop20h 20mMultiple Airlines
Deal found 12/9$615
This FlightHub deal was found by Cheapflights users on 12/9. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 12/314:20 pmORD - SOF
1 stop13h 30mLufthansa
mié. 1/146:05 amSOF - ORD
1 stop20h 20mLufthansa
Deal found 12/9$621
This FlightHub deal was found by Cheapflights users on 12/11. 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.
dom. 12/286:10 pmORD - SOF
2 stops20h 35mLufthansa
lun. 3/22:20 pmSOF - ORD
1 stop13h 45mLufthansa
Deal found 12/11$625
This FlightHub deal was found by Cheapflights users on 12/11. 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.
dom. 12/286:10 pmORD - SOF
2 stops20h 35mMultiple Airlines
lun. 3/21:45 pmSOF - ORD
2 stops29h 33mMultiple Airlines
Deal found 12/11$630
This United Airlines deal was found by Cheapflights users on 12/10. 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.
mié. 12/105:55 pmORD - SOF
2 stops20h 50mUnited Airlines
dom. 2/16:10 amSOF - ORD
1 stop15h 15mUnited Airlines
Deal found 12/10$634
This United Airlines deal was found by Cheapflights users on 12/10. 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.
mié. 12/105:55 pmORD - SOF
2 stops20h 50mUnited Airlines
jue. 1/296:05 amSOF - ORD
1 stop20h 20mUnited Airlines
Deal found 12/10$635
This United Airlines deal was found by Cheapflights users on 12/10. 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.
mié. 12/105:55 pmORD - SOF
2 stops20h 50mUnited Airlines
lun. 2/26:10 amSOF - ORD
2 stops22h 00mUnited Airlines
Deal found 12/10$637
This KAYAK deal was found by Cheapflights users on 12/9. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 12/96:10 pmORD - SOF
2 stops20h 35mLufthansa
vie. 1/306:10 amSOF - ORD
1 stop15h 15mLufthansa
Deal found 12/9$639
This KAYAK deal was found by Cheapflights users on 12/9. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 12/96:10 pmORD - SOF
2 stops20h 35mLufthansa
jue. 1/296:05 amSOF - ORD
1 stop20h 20mLufthansa
Deal found 12/9$641
This United Airlines deal was found by Cheapflights users on 12/10. 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.
mié. 12/105:55 pmORD - SOF
2 stops20h 50mUnited Airlines
vie. 2/136:05 amSOF - ORD
2 stops21h 40mUnited Airlines
Deal found 12/10$642
This United Airlines deal was found by Cheapflights users on 12/10. 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.
mié. 12/105:55 pmORD - SOF
2 stops20h 50mUnited Airlines
mié. 2/116:10 amSOF - ORD
2 stops22h 56mUnited Airlines
Deal found 12/10$644
This KLM deal was found by Cheapflights users on 12/9. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 12/2411:48 amMDW - SOF
2 stops18h 17mKLM
mié. 1/147:00 amSOF - MDW
2 stops19h 32mKLM
Deal found 12/9$898

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 diciembre 12, 2025.

Most accurate provider

Justfly.com
3 stars

Most trusted provider

Justfly.com
3 stars

Round-trip from

$541
(United Airlines)

One-way from

$301
(Kiwi.com)

Popular in

June

Cheapest in

February

Average price

$760
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 ($263 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 5% potential price decrease ($38 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 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 diciembre 12, 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

jue. 1/29

8:05 am-10:45 pm

2 stops30h 40m

Sofia

lun. 2/2

2:20 pm-3:29 pm

2 stops33h 09m

$541

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

jue. 3/19

1:35 pm-1:55 pm

2 stops17h 20m

Sofia

mar. 3/24

7:00 am-8:52 am

2 stops32h 52m

$544

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

lun. 1/12

9:55 pm-5:50 pm

1 stop11h 55m

Sofia

dom. 1/18

2:35 pm-7:55 pm

2 stops37h 20m

$599

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

mié. 3/4

3:35 pm-1:15 pm

2 stops13h 40m

Sofia

dom. 3/8

6:05 am-8:05 pm

2 stops22h 00m

$603

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

jue. 2/12

6:04 am-3:05 am

2 stops37h 01m

Sofia

jue. 2/19

4:00 pm-3:00 pm

1 stop31h 00m

$607

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

jue. 1/22

9:05 pm-10:45 pm

2 stops17h 40m

Sofia

sáb. 2/14

6:25 am-3:20 pm

1 stop16h 55m

$609

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

mié. 1/14

9:50 pm-6:20 pm

1 stop12h 30m

Sofia

mar. 1/20

6:00 am-11:10 am

1 stop13h 10m

$610

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

jue. 1/29

9:50 pm-10:45 pm

1 stop16h 55m

Sofia

dom. 2/1

6:10 am-3:20 pm

1 stop17h 10m

$610

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

dom. 1/25

9:50 pm-6:20 pm

1 stop12h 30m

Sofia

dom. 2/1

6:10 am-1:25 pm

1 stop15h 15m

$610

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

lun. 1/19

6:00 pm-1:15 pm

1 stop11h 15m

Sofia

mar. 2/3

6:00 am-11:10 am

1 stop13h 10m

$610

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/9

Showing 1-10 of 40 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 $473). 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.

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 diciembre 12, 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 32% 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 11h 55m. United Airlines provides one of the quickest options available for as low as $599. 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 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 $473). 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

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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 diciembre 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
Turkish AirlinesCheapest$509Average$763FlexibilityNo cancel feeOn-time77%
KLMCheapest$569Average$675FlexibilityNo cancel feeOn-time75%
Air FranceCheapest$585Average$624FlexibilityNo cancel feeOn-time77%
LufthansaCheapest$588Average$876FlexibilityNo cancel feeOn-time76%
LOTCheapest$589Average$976FlexibilityNo cancel feeOn-time81%
SWISSCheapest$593Average$808FlexibilityNo cancel feeOn-time79%
United AirlinesCheapest$596Average$783FlexibilityNo cancel feeOn-time69%
Austrian AirlinesCheapest$606Average$971FlexibilityNo cancel feeOn-time78%
British AirwaysCheapest$611Average$754FlexibilityNo cancel feeOn-time70%
Air SerbiaCheapest$634Average$996FlexibilityNo cancel feeOn-timeN/A

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