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

KLM and Air France 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 35% of people opting to fly with this airline when traveling to Sofia. Keep in mind that there are 12 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 February 2026, there are 12 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.

$248 Cheap Flights from Illinois to Sofia in 2026

1 adult

0 bags

Discover deals from 900+ travel sites with momondo.

Save money when you book flights with momondo

Big names and deals

Search 100s of travel sites to compare prices.

Filter for what you want

Free Wi-Fi? Stopover? Instantly customize your results.

Trusted and free

We’re completely free to use - no hidden charges or fees.

Price Alerts

Not ready to book? to track prices.

Search flight deals

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.

8:20 pm - 3:10 pm

ORD

SOF

34h 50m

1 stop

4:00 pm - 11:05 am

SOF

ORD

26h 05m

1 stop

$517Turkish Airlines

Sun, Mar 1 - Sun, Mar 8

8:20 pm - 3:10 pm

ORD

SOF

34h 50m

1 stop

4:00 pm - 11:05 am

SOF

ORD

26h 05m

1 stop

$524Turkish Airlines

Wed, Mar 4 - Wed, Mar 18

6:35 pm - 11:00 pm

STL

SOF

20h 25m

2 stops

6:10 am - 9:08 pm

SOF

STL

22h 58m

2 stops

$531Lufthansa

Sun, Mar 29 - Tue, Apr 14

3:30 pm - 6:10 pm

STL

SOF

18h 40m

1 stop

6:10 am - 3:24 pm

SOF

STL

41h 14m

2 stops

$552Multiple Airlines

Sun, Mar 29 - Tue, Apr 14

3:30 pm - 6:05 pm

STL

SOF

18h 35m

1 stop

6:20 am - 1:25 pm

SOF

STL

15h 05m

1 stop

$554Lufthansa

Wed, Apr 1 - Sun, Apr 19

6:05 pm - 11:10 pm

STL

SOF

21h 05m

2 stops

6:10 am - 10:28 pm

SOF

STL

24h 18m

2 stops

$600United Airlines

Wed, Apr 1 - Sun, Apr 19

1:49 pm - 1:55 pm

MDW

SOF

16h 06m

2 stops

7:00 am - 4:14 pm

SOF

MDW

17h 14m

2 stops

$626Multiple Airlines

Fri, Feb 20 - Sat, Feb 28

1:10 pm - 2:00 pm

MDW

SOF

16h 50m

2 stops

7:00 am - 5:58 pm

SOF

MDW

18h 58m

2 stops

$630KLM

Wed, Apr 8 - Sun, Apr 19

1:28 pm - 2:05 pm

MDW

SOF

16h 37m

2 stops

7:00 am - 4:14 pm

SOF

MDW

17h 14m

2 stops

$632KLM

Sat, Feb 21 - Sat, Feb 28

6:00 pm - 10:45 pm

STL

SOF

20h 45m

2 stops

6:10 am - 10:59 pm

SOF

STL

24h 49m

2 stops

$747United Airlines

Thu, Feb 26 - Mon, Mar 2

United Airlines flights from Illinois to Sofia

Our best United Airlines deals on Illinois to Sofia flight tickets

United Airlines

Apr 1

STL6:05 pmLambert-St Louis

21h 05m

2 stops

SOF11:10 pmSofia

Apr 19

SOF6:10 amSofia

24h 18m

2 stops

STL10:28 pmLambert-St Louis

$600

United Airlines

Feb 14

ORD1:55 pmChicago O'Hare Intl

15h 20m

2 stops

SOF1:15 pmSofia

Mar 1

SOF2:25 pmSofia

13h 40m

1 stop

ORD8:05 pmChicago O'Hare Intl

$618

United Airlines

Feb 8

ORD2:18 pmChicago O'Hare Intl

14h 42m

2 stops

SOF1:00 pmSofia

Mar 5

SOF6:05 amSofia

17h 58m

2 stops

ORD4:03 pmChicago O'Hare Intl

$630

Turkish Airlines flights from Illinois to Sofia

Our best Turkish Airlines deals on Illinois to Sofia flight tickets

Turkish Airlines

Mar 1

ORD8:20 pmChicago O'Hare Intl

34h 50m

1 stop

SOF3:10 pmSofia

Mar 8

SOF4:00 pmSofia

26h 05m

1 stop

ORD11:05 amChicago O'Hare Intl

$517

Turkish Airlines

Mar 4

ORD8:20 pmChicago O'Hare Intl

34h 50m

1 stop

SOF3:10 pmSofia

Mar 18

SOF4:00 pmSofia

26h 05m

1 stop

ORD11:05 amChicago O'Hare Intl

$524

Turkish Airlines

Feb 26

ORD8:20 pmChicago O'Hare Intl

28h 25m

1 stop

SOF8:45 amSofia

Mar 8

SOF4:00 pmSofia

26h 05m

1 stop

ORD11:05 amChicago O'Hare Intl

$525

Fly from

Fly to

Route

Depart

Return

Price

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Sun 3/1

8:20 pm-3:10 pm

1 stop34h 50m

Sofia

Sun 3/8

4:00 pm-11:05 am

1 stop26h 05m

$517

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Wed 3/4

8:20 pm-3:10 pm

1 stop34h 50m

Sofia

Wed 3/18

4:00 pm-11:05 am

1 stop26h 05m

$524

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Sun 3/29

6:35 pm-11:00 pm

2 stops20h 25m

Sofia

Tue 4/14

6:10 am-9:08 pm

2 stops22h 58m

$531

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Sun 3/29

3:30 pm-6:10 pm

1 stop18h 40m

Sofia

Tue 4/14

6:10 am-3:24 pm

2 stops41h 14m

$552

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Wed 4/1

3:30 pm-6:05 pm

1 stop18h 35m

Sofia

Sun 4/19

6:20 am-1:25 pm

1 stop15h 05m

$554

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Wed 4/1

6:05 pm-11:10 pm

2 stops21h 05m

Sofia

Sun 4/19

6:10 am-10:28 pm

2 stops24h 18m

$600

ChicagoSofia

MDW - SOF

MDWSOF

Chicago Midway

Fri 2/20

1:49 pm-1:55 pm

2 stops16h 06m

Sofia

Sat 2/28

7:00 am-4:14 pm

2 stops17h 14m

$626

ChicagoSofia

MDW - SOF

MDWSOF

Chicago Midway

Wed 4/8

1:10 pm-2:00 pm

2 stops16h 50m

Sofia

Sun 4/19

7:00 am-5:58 pm

2 stops18h 58m

$630

ChicagoSofia

MDW - SOF

MDWSOF

Chicago Midway

Sat 2/21

1:28 pm-2:05 pm

2 stops16h 37m

Sofia

Sat 2/28

7:00 am-4:14 pm

2 stops17h 14m

$632

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Thu 2/26

6:00 pm-10:45 pm

2 stops20h 45m

Sofia

Mon 3/2

6:10 am-10:59 pm

2 stops24h 49m

$747

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 $582, 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 $589.

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 $747 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 $711 on momondo.

Can stopping save me money on Illinois to Sofia flights?

You could potentially save up to 23% 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

Fastest flight time	12h 35m
Direct flights	None

The fastest flight from Illinois to Sofia takes 12h 35m

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 February 2026, there are 12 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
ITA Airways	PriceFrom $469	Free Cancellation	Rating 6.7 1,145 reviews	Search ITA Airways flights
Turkish Airlines	PriceFrom $520	Free Cancellation	Rating 7.3 4,211 reviews	Search Turkish Airlines flights
KLM	PriceFrom $533	Free Cancellation	Rating 7.7 1,449 reviews	Search KLM flights
United Airlines	PriceFrom $566	Free Cancellation	Rating 7.4 9,236 reviews	Search United Airlines flights
SWISS	PriceFrom $569	Free Cancellation	Rating 7.6 1,864 reviews	Search SWISS flights
Air France	PriceFrom $585	Free Cancellation	Rating 7.4 1,532 reviews	Search Air France flights
Lufthansa	PriceFrom $586	Free Cancellation	Rating 6.8 7,761 reviews	Search Lufthansa flights
LOT	PriceFrom $590	Free Cancellation	Rating 7.5 1,179 reviews	Search LOT flights
Austrian Airlines	PriceFrom $606	Free Cancellation	Rating 7.5 896 reviews	Search Austrian Airlines flights
British Airways	PriceFrom $611	Free Cancellation	Rating 6.7 7,716 reviews	Search British Airways 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

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.

Start using Trips

Find my bookings

Get notified when prices go down

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

1 adult

Sat 3/7

Sat 3/14

Email me momondo's favorite deals

By creating a price alert you accept our terms of use and privacy policy.

Find better results for your trip to Bulgaria

Airlines

Cabin classes

Other Bulgaria destinations

Other flights from Illinois

Complete your trip

Feeling lucky

Fly your favorite airline to Sofia

Cheap flights from Illinois to Sofia from $248

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 2/22. 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

Trusted and free

Trusted and free

Price Alerts

Price Alerts

Find the cheapest flights from Illinois to Sofia

Cheap round-trip flights

Cheap one-way flights

Cheap last minute flights

United Airlines flights from Illinois to Sofia

Our best United Airlines deals on Illinois to Sofia flight tickets

Turkish Airlines flights from Illinois to Sofia

Our best Turkish Airlines deals on Illinois to Sofia flight tickets

momondo Fare Finder

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

See travel insights to Sofia from

How to get the cheapest flight ticket from Illinois to Sofia

What is the cheapest month to fly 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 23% on your flight if you consider stops on a Illinois to Sofia flight.

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

KLM and Air France 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

Fastest flight time

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

Cabin classes currently available on flights to Sofia

List of cabin classes available on flights landing in Sofia. Availability may vary depending on flight origin and airline.

Popular cities in Bulgaria

Popular flights according to clicks in the last 7 days on momondo

Fly to other destinations from Illinois

According to popular flight searches on momondo this year

Complete your trip to Sofia

Explore popular destinations other users love

According to popular flight searches on momondo this year