Latest deals
Insights
FAQs
Reviews
Price Alerts

Cheap flights from Illinois to Sofia from $256

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 1/11. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
1 adult
0 bags

Discover deals from 900+ travel sites with momondo.

Save money when you book flights with momondo

Big names and deals

Big names and deals

Search 100s of travel sites to compare prices.

Filter for what you want

Filter for what you want

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

Trusted and free

Trusted and free

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

Price Alerts

Price Alerts

Not ready to book? to track prices.
Search flight deals

Find the cheapest flights from Illinois to Sofia

Cheap round-trip flights

Enter your travel dates to find the best prices.
Lufthansa Logo
6:40 pm - 6:20 pm
STL
-
SOF
15h 40m2 stops
Lufthansa Logo
6:10 am - 10:58 pm
SOF
-
STL
24h 48m2 stops
$546Lufthansa
Fri, Jan 30 - Fri, Feb 6
Turkish Airlines Logo
11:25 am - 3:00 pm
ORD
-
SOF
19h 35m1 stop
Turkish Airlines Logo
9:35 am - 10:05 pm
SOF
-
ORD
20h 30m1 stop
$556Turkish Airlines
Tue, May 5 - Wed, Oct 21
Turkish Airlines Logo
11:50 am - 3:10 pm
ORD
-
SOF
19h 20m1 stop
Turkish Airlines Logo
9:35 am - 7:25 pm
SOF
-
ORD
16h 50m1 stop
$561Turkish Airlines
Fri, Mar 6 - Mon, Mar 9
Multiple Airlines Logo
5:50 pm - 6:00 pm
ORD
-
SOF
16h 10m2 stops
Multiple Airlines Logo
6:25 am - 1:25 pm
SOF
-
ORD
15h 00m1 stop
$569Multiple Airlines
Sat, Jan 31 - Sat, Feb 7
LOT Logo
9:55 pm - 5:50 pm
ORD
-
SOF
11h 55m1 stop
LOT Logo
2:35 pm - 8:00 pm
SOF
-
ORD
13h 25m1 stop
$578LOT
Sat, Jan 31 - Sat, Feb 7
Multiple Airlines Logo
12:46 pm - 1:55 pm
MDW
-
SOF
17h 09m2 stops
Multiple Airlines Logo
7:00 am - 5:40 pm
SOF
-
MDW
18h 40m2 stops
$624Multiple Airlines
Tue, Feb 24 - Sun, Mar 8
KLM Logo
1:00 pm - 2:00 pm
MDW
-
SOF
17h 00m2 stops
KLM Logo
7:00 am - 4:25 pm
SOF
-
MDW
17h 25m2 stops
$628KLM
Mon, Apr 20 - Mon, Apr 27
KLM Logo
1:28 pm - 2:05 pm
MDW
-
SOF
16h 37m2 stops
KLM Logo
7:00 am - 5:55 pm
SOF
-
MDW
17h 55m2 stops
$630KLM
Wed, Mar 4 - Mon, Mar 9
United Airlines Logo
6:40 pm - 10:45 pm
STL
-
SOF
20h 05m2 stops
United Airlines Logo
2:25 pm - 10:13 am
SOF
-
STL
27h 48m2 stops
$652United Airlines
Wed, Jan 14 - Sun, Jan 18
United Airlines Logo
9:57 am - 10:45 pm
STL
-
SOF
28h 48m2 stops
United Airlines Logo
2:25 pm - 7:27 pm
SOF
-
STL
37h 02m2 stops
$666United Airlines
Wed, Jan 14 - Sun, Jan 18

United Airlines flights from Illinois to Sofia

Our best United Airlines deals on Illinois to Sofia flight tickets
United Airlines
Jan 30
STL3:50 pmLambert-St Louis
22h 55m
1 stop
SOF10:45 pmSofia
Feb 3
SOF6:00 amSofia
41h 15m
2 stops
STL3:15 pmLambert-St Louis
$550
Find similar
United Airlines
Jan 30
STL3:50 pmLambert-St Louis
18h 30m
2 stops
SOF6:20 pmSofia
Feb 3
SOF6:00 amSofia
23h 59m
2 stops
STL9:59 pmLambert-St Louis
$577
Find similar
United Airlines
Jan 29
ORD9:50 pmChicago O'Hare Intl
16h 55m
1 stop
SOF10:45 pmSofia
Feb 2
SOF6:10 amSofia
17h 10m
1 stop
ORD3:20 pmChicago O'Hare Intl
$611
Find similar

KLM flights from Illinois to Sofia

Our best KLM deals on Illinois to Sofia flight tickets
KLM
Apr 20
MDW1:00 pmChicago Midway
17h 00m
2 stops
SOF2:00 pmSofia
Apr 27
SOF7:00 amSofia
17h 25m
2 stops
MDW4:25 pmChicago Midway
$628
Find similar
KLM
Mar 4
MDW1:28 pmChicago Midway
16h 37m
2 stops
SOF2:05 pmSofia
Mar 9
SOF7:00 amSofia
17h 55m
2 stops
MDW5:55 pmChicago Midway
$630
Find similar
KLM
Jan 10
MDW1:28 pmChicago Midway
16h 37m
2 stops
SOF2:05 pmSofia
Feb 2
SOF7:00 amSofia
18h 29m
2 stops
MDW5:29 pmChicago Midway
$672
Find similar

momondo 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, momondo users made 832,500 searches. Data last updated December 18, 2025.
Use the filters below to find and compare flights from Illinois to Sofia that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Fri 1/30

6:40 pm-6:20 pm

2 stops15h 40m

Sofia

Fri 2/6

6:10 am-10:58 pm

2 stops24h 48m

$546

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Tue 5/5

11:25 am-3:00 pm

1 stop19h 35m

Sofia

Wed 10/21

9:35 am-10:05 pm

1 stop20h 30m

$556

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Fri 3/6

11:50 am-3:10 pm

1 stop19h 20m

Sofia

Mon 3/9

9:35 am-7:25 pm

1 stop16h 50m

$561

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Sat 1/31

5:50 pm-6:00 pm

2 stops16h 10m

Sofia

Sat 2/7

6:25 am-1:25 pm

1 stop15h 00m

$569

ChicagoSofia

ORD - SOF

ORDSOF

Chicago O'Hare Intl

Sat 1/31

9:55 pm-5:50 pm

1 stop11h 55m

Sofia

Sat 2/7

2:35 pm-8:00 pm

1 stop13h 25m

$578

ChicagoSofia

MDW - SOF

MDWSOF

Chicago Midway

Tue 2/24

12:46 pm-1:55 pm

2 stops17h 09m

Sofia

Sun 3/8

7:00 am-5:40 pm

2 stops18h 40m

$624

ChicagoSofia

MDW - SOF

MDWSOF

Chicago Midway

Mon 4/20

1:00 pm-2:00 pm

2 stops17h 00m

Sofia

Mon 4/27

7:00 am-4:25 pm

2 stops17h 25m

$628

ChicagoSofia

MDW - SOF

MDWSOF

Chicago Midway

Wed 3/4

1:28 pm-2:05 pm

2 stops16h 37m

Sofia

Mon 3/9

7:00 am-5:55 pm

2 stops17h 55m

$630

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Wed 1/14

6:40 pm-10:45 pm

2 stops20h 05m

Sofia

Sun 1/18

2:25 pm-10:13 am

2 stops27h 48m

$652

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Wed 1/14

9:57 am-10:45 pm

2 stops28h 48m

Sofia

Sun 1/18

2:25 pm-7:27 pm

2 stops37h 02m

$666

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first
1
2

See travel insights to Sofia from

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?

The cheapest month to fly to Sofia from Illinois is in February. Flight prices, which tend to average around $565, 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 $753 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 $716 on momondo.

Can stopping save me money on Illinois to Sofia flights?

You could potentially save up to 14% 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

13h 00m

Direct flights

None
The fastest flight from Illinois to Sofia takes 13h 00m
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?

  • 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 AirlinesPriceFrom $511Free CancellationRating
7.3
4,105 reviews
Search Turkish Airlines flights
KLMPriceFrom $569Free CancellationRating
7.7
1,428 reviews
Search KLM flights
Air FrancePriceFrom $585Free CancellationRating
7.4
1,507 reviews
Search Air France flights
United AirlinesPriceFrom $585Free CancellationRating
7.4
9,092 reviews
Search United Airlines flights
LOTPriceFrom $587Free CancellationRating
7.5
1,149 reviews
Search LOT flights
LufthansaPriceFrom $588Free CancellationRating
6.8
7,635 reviews
Search Lufthansa flights
SWISSPriceFrom $593Free CancellationRating
7.5
1,815 reviews
Search SWISS flights
Austrian AirlinesPriceFrom $606Free CancellationRating
7.6
879 reviews
Search Austrian Airlines flights
British AirwaysPriceFrom $611Free CancellationRating
6.7
7,585 reviews
Search British Airways flights
Air SerbiaPriceFrom $632Free CancellationRating
6.2
210 reviews
Search Air Serbia flights

Traveling to a place near Sofia?

Book flights to Sofia if you plan to visit one of these locations
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 1/17
Sat 1/24
By creating a price alert you accept our terms of use and privacy policy.

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
Lufthansa
Turkish Airlines
LOT
United Airlines
Austrian Airlines
Air Serbia
SWISS
KLM
British Airways
Air France