What is the cheapest airline that flies from Illinois to Sofia?

Air Serbia, British Airways, and Lufthansa are the most popular carriers operating from Illinois to Sofia

What airlines fly to Sofia?

Lufthansa, Turkish Airlines and LOT are the top three most popular airlines that fly to Sofia from Illinois according to our data. Lufthansa is the first choice among our users, with 32% of people opting to fly with this airline when traveling to Sofia. Keep in mind that there are 10 different airlines that fly to Sofia on a routine basis, so you have a few additional options to choose from.

When did momondo last update prices for flights from Illinois to Sofia Airport?

Prices for flights from Illinois to Sofia Airport refresh daily.

How many operators does momondo search for flights from Illinois to Sofia Airport?

As of October 2025, there are 10 operators available to choose from for flights from Illinois to Sofia Airport.

How old do you have to be to fly from Illinois to Sofia Airport?

Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Illinois to Sofia Airport.

What documentation or ID do you need to fly to Sofia Airport?

The required travel and health documents for your Sofia Airport trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at Sofia Airport. We recommend that you seek guidance from your airline or a reliable third party such as IATA.

$270 Cheap Flights from Illinois to Sofia in 2025/26

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Find the cheapest flights from Illinois to Sofia

Round-trip

One-way

Last minute

Cheap round-trip flights

Enter your travel dates to find the best prices.

11:22 am - 6:20 pmSTL-SOF

22h 58m2 stops

6:10 am - 11:59 pmSOF-STL

25h 49m2 stops

$540Lufthansa

Find Deal

Fri, Jan 23 - Sun, Feb 1

9:55 am - 10:45 pmSTL-SOF

28h 50m2 stops

6:10 am - 9:00 pmSOF-STL

22h 50m2 stops

$543United Airlines

Find Deal

Thu, Feb 12 - Sun, Feb 22

11:25 am - 8:45 amORD-SOF

13h 20m1 stop

3:50 pm - 9:40 amSOF-ORD

25h 50m1 stop

$559Turkish Airlines

Find Deal

Mon, Apr 27 - Mon, May 11

9:55 pm - 1:50 pmORD-SOF

31h 55m2 stops

2:35 pm - 8:00 pmSOF-ORD

13h 25m1 stop

$560LOT

Find Deal

Sun, Feb 8 - Thu, Mar 5

11:50 am - 8:45 amORD-SOF

12h 55m1 stop

9:35 am - 6:25 pmSOF-ORD

16h 50m1 stop

$563Turkish Airlines

Find Deal

Thu, Nov 13 - Fri, Mar 6

9:55 pm - 5:50 pmORD-SOF

11h 55m1 stop

6:35 pm - 9:00 pmSOF-ORD

33h 25m1 stop

$564LOT

Find Deal

Tue, Nov 18 - Mon, Mar 16

4:05 pm - 1:40 pmSTL-SOF

37h 35m2 stops

6:10 am - 10:58 pmSOF-STL

24h 48m3 stops

$565Multiple Airlines

Find Deal

Fri, Jan 23 - Sun, Feb 1

5:20 pm - 1:55 pmORD-SOF

12h 35m1 stop

7:00 am - 2:20 pmSOF-ORD

15h 20m1 stop

$569Multiple Airlines

Find Deal

Thu, Jan 1 - Mon, Jan 26

12:27 pm - 2:05 pmORD-SOF

17h 38m2 stops

7:00 am - 5:37 pmSOF-ORD

18h 37m2 stops

$574KLM

Find Deal

Sun, Feb 8 - Thu, Mar 5

1:35 pm - 2:05 pmORD-SOF

16h 30m2 stops

7:00 am - 2:20 pmSOF-ORD

15h 20m1 stop

$579KLM

Find Deal

Thu, Jan 1 - Mon, Jan 26

Turkish Airlines flights from Illinois to Sofia

Our best Turkish Airlines deals on Illinois to Sofia flight tickets

Turkish Airlines

Apr 27

ORD11:25 amChicago O'Hare Intl

13h 20m

1 stop

SOF8:45 amSofia

May 11

SOF3:50 pmSofia

25h 50m

1 stop

ORD9:40 amChicago O'Hare Intl

$559

Find similar

Turkish Airlines

Nov 13

ORD11:50 amChicago O'Hare Intl

12h 55m

1 stop

SOF8:45 amSofia

Mar 6

SOF9:35 amSofia

16h 50m

1 stop

ORD6:25 pmChicago O'Hare Intl

$563

Find similar

Turkish Airlines

Nov 25

ORD11:50 amChicago O'Hare Intl

12h 55m

1 stop

SOF8:45 amSofia

Dec 2

SOF9:35 amSofia

32h 30m

1 stop

ORD10:05 amChicago O'Hare Intl

$575

Find similar

KLM flights from Illinois to Sofia

Our best KLM deals on Illinois to Sofia flight tickets

KLM

Feb 8

ORD12:27 pmChicago O'Hare Intl

17h 38m

2 stops

SOF2:05 pmSofia

Mar 5

SOF7:00 amSofia

18h 37m

2 stops

ORD5:37 pmChicago O'Hare Intl

$574

Find similar

KLM

Jan 1

ORD1:35 pmChicago O'Hare Intl

16h 30m

2 stops

SOF2:05 pmSofia

Jan 26

SOF7:00 amSofia

15h 20m

1 stop

ORD2:20 pmChicago O'Hare Intl

$579

Find similar

KLM

Dec 4

ORD7:00 amChicago O'Hare Intl

23h 05m

2 stops

SOF2:05 pmSofia

Dec 13

SOF7:00 amSofia

15h 20m

1 stop

ORD2:20 pmChicago O'Hare Intl

$589

Find similar

Fly from

Fly to

Route

Depart

Return

Price

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Fri 1/23

11:22 am-6:20 pm

2 stops22h 58m

Sofia

Sun 2/1

6:10 am-11:59 pm

2 stops25h 49m

$540

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Thu 2/12

9:55 am-10:45 pm

2 stops28h 50m

Sofia

Sun 2/22

6:10 am-9:00 pm

2 stops22h 50m

$543

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Mon 4/27

11:25 am-8:45 am

1 stop13h 20m

Sofia

Mon 5/11

3:50 pm-9:40 am

1 stop25h 50m

$559

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Sun 2/8

9:55 pm-1:50 pm

2 stops31h 55m

Sofia

Thu 3/5

2:35 pm-8:00 pm

1 stop13h 25m

$560

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Thu 11/13

11:50 am-8:45 am

1 stop12h 55m

Sofia

Fri 3/6

9:35 am-6:25 pm

1 stop16h 50m

$563

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Tue 11/18

9:55 pm-5:50 pm

1 stop11h 55m

Sofia

Mon 3/16

6:35 pm-9:00 pm

1 stop33h 25m

$564

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Fri 1/23

4:05 pm-1:40 pm

2 stops37h 35m

Sofia

Sun 2/1

6:10 am-10:58 pm

3 stops24h 48m

$565

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Thu 1/1

5:20 pm-1:55 pm

1 stop12h 35m

Sofia

Mon 1/26

7:00 am-2:20 pm

1 stop15h 20m

$569

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Sun 2/8

12:27 pm-2:05 pm

2 stops17h 38m

Sofia

Thu 3/5

7:00 am-5:37 pm

2 stops18h 37m

$574

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Thu 1/1

1:35 pm-2:05 pm

2 stops16h 30m

Sofia

Mon 1/26

7:00 am-2:20 pm

1 stop15h 20m

$579

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

How to get the cheapest flight ticket from Illinois to Sofia

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

Prices

Airlines

What is the cheapest month to fly to Sofia?

The cheapest month to fly to Sofia from Illinois is in February. Flight prices, which tend to average around $568, are often lower during this time because this is during the off-season. If you aren’t able to travel during the month of February, then book flights to Sofia from Illinois during March instead. Flights to Sofia in March, while not as cheap as those in February, still average around $587.

What is the cheapest day to depart on your flight to Sofia?

According to our data, Thursday is the cheapest day to fly to Sofia from Illinois. The lowest ticket price found for a Thursday departure recently was $871. Keep in mind that prices can always vary depending on your route and whether or not you are flying domestic or international. Flights from Illinois to Sofia on a Saturday will generally be more expensive and average around $1,039. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.

What is the cheapest time of day to depart on your flight to Sofia?

In the morning is the cheapest time of day to fly from Illinois to Sofia when you can find flight prices for as low as $801. Flying to Sofia in the morning is an ideal time because this is during off-peak travel hours. At noon is when there is more demand to fly to Sofia, so prices are often more expensive at around $1,145 per ticket.

How far in advance should I book a flight to Sofia?

You are more likely to see cheaper flights to Sofia from Illinois when booking weeks ahead of your departure date. In general, you can expect to find flights to Sofia for around $763 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Sofia from Illinois for as low as $710 on momondo.

Can stopping save me money on Illinois to Sofia flights?

You could potentially save up to 49% on your flight if you consider stops on a Illinois to Sofia flight.

Cheap Illinois to Sofia flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Illinois to Sofia

Direct flights	None

There are no direct flights from Illinois to Sofia. There are no popular flight routes from Illinois to Sofia.

Search flight deals

When did momondo last update prices for flights from Illinois to Sofia Airport?
Prices for flights from Illinois to Sofia Airport refresh daily.
How many operators does momondo search for flights from Illinois to Sofia Airport?
As of October 2025, there are 10 operators available to choose from for flights from Illinois to Sofia Airport.
How old do you have to be to fly from Illinois to Sofia Airport?
Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Illinois to Sofia Airport.
What documentation or ID do you need to fly to Sofia Airport?
The required travel and health documents for your Sofia Airport trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at Sofia Airport. We recommend that you seek guidance from your airline or a reliable third party such as IATA.

Best airlines flying from Illinois to Sofia

Compare and see reviews for airlines that fly from Illinois to Sofia with momondo

Airline	Rating	Free Cancellation	Price
Turkish Airlines	PriceFrom $513	Free Cancellation	Rating 7.3 4,033 reviews	Search Turkish Airlines flights
KLM	PriceFrom $533	Free Cancellation	Rating 7.7 1,406 reviews	Search KLM flights
LOT	PriceFrom $565	Free Cancellation	Rating 7.6 1,135 reviews	Search LOT flights
Air France	PriceFrom $585	Free Cancellation	Rating 7.4 1,482 reviews	Search Air France flights
Lufthansa	PriceFrom $590	Free Cancellation	Rating 6.8 7,542 reviews	Search Lufthansa flights
SWISS	PriceFrom $593	Free Cancellation	Rating 7.5 1,775 reviews	Search SWISS flights
United Airlines	PriceFrom $600	Free Cancellation	Rating 7.4 8,997 reviews	Search United Airlines flights
Austrian Airlines	PriceFrom $606	Free Cancellation	Rating 7.6 862 reviews	Search Austrian Airlines flights
British Airways	PriceFrom $611	Free Cancellation	Rating 6.7 7,488 reviews	Search British Airways flights
Air Serbia	PriceFrom $634	Free Cancellation	Rating 6.2 205 reviews	Search Air Serbia flights

Bansko

Borovets

Velingrad

Sandanski

Why use momondo?

Why should I use momondo to find a flight deal from Illinois to Sofia?

momondo compares prices from hundreds of airlines and agents so you can find and book the best deal on flights from Illinois to Sofia. Millions of users trust and use momondo every year so you are in good hands.

Can I find flights from Illinois to Sofia with flexible booking policies on momondo?

momondo does allow users to show only those flights to Sofia from Illinois which offer a flexible booking policy as well as other useful filters and features.

How can momondo help me find flights from Illinois to Sofia?

momondo helps you find the best flight between Illinois and Sofia by providing filters to narrow your choice of flights to those matching your criteria. You can select flights based on numerous factors such as price, departure and landing times, airport and airline.

I’m not ready to book a flight from Illinois to Sofia right now. Can momondo alert me if prices change?

Of course. momondo tracks the price of Illinois to Sofia flights. All you need is a valid email address and we will do the rest; it is that quick and easy.

An easier way to manage your Sofia trip

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Cheap flights from Illinois to Sofia from $270

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Illinois to Sofia departing on 11/15. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

Big names and deals

Big names and deals

Filter for what you want

Filter for what you want

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Find the cheapest flights from Illinois to Sofia

Cheap round-trip flights

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Cheap last minute flights

Turkish Airlines flights from Illinois to Sofia

Our best Turkish Airlines deals on Illinois to Sofia flight tickets

KLM flights from Illinois to Sofia

Our best KLM deals on Illinois to Sofia flight tickets

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How to get the cheapest flight ticket from Illinois to Sofia

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the cheapest month to fly to Sofia?

What is the cheapest day to depart on your flight to Sofia?

What is the cheapest time of day to depart on your flight to Sofia?

How far in advance should I book a flight to Sofia?

Can stopping save me money on Illinois to Sofia flights?

You could potentially save up to 49% on your flight if you consider stops on a Illinois to Sofia flight.

What is the cheapest airline that flies from Illinois to Sofia?

Air Serbia, British Airways, and Lufthansa are the most popular carriers operating from Illinois to Sofia

What airlines fly to Sofia?

Cheap Illinois to Sofia flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Illinois to Sofia

Direct flights

When did momondo last update prices for flights from Illinois to Sofia Airport?

How many operators does momondo search for flights from Illinois to Sofia Airport?

How old do you have to be to fly from Illinois to Sofia Airport?

What documentation or ID do you need to fly to Sofia Airport?

Best airlines flying from Illinois to Sofia

Compare and see reviews for airlines that fly from Illinois to Sofia with momondo

Traveling to a place near Sofia?

Why use momondo?

Why should I use momondo to find a flight deal from Illinois to Sofia?

Can I find flights from Illinois to Sofia with flexible booking policies on momondo?

How can momondo help me find flights from Illinois to Sofia?

I’m not ready to book a flight from Illinois to Sofia right now. Can momondo alert me if prices change?

An easier way to manage your Sofia trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.

Find better results for your trip to Bulgaria

Fly your favorite airline to Sofia

Airlines are sorted and displayed according to clicks in the past 7 days on momondo