$358 Find Cheap Flights from Sofia to Illinois

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Sofia to Illinois departing on 9/16. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Illinois

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Sofia to Illinois.
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Sofia to Illinois.
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Cheap Flights from Sofia to Illinois

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
Chicago
Chicago1 stop$710
St. Louis
St. Louis2 stops$1,206
Chicago
Chicago1 stop$710
St. Louis
St. Louis2 stops$1,206

Book Cheap Sofia to Illinois Plane Tickets

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Sofia to Illinois that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Sofia to Illinois

Wed, Sep 9 - Wed, Sep 30
LOT Logo
5:25 am - 7:50 pm
SOF
-
ORD
22h 25m
1 stop
LOT Logo
9:50 pm - 1:55 am
ORD
-
SOF
20h 05m
1 stop
$710LOT
Wed, Sep 23 - Wed, Oct 14
LOT Logo
5:25 am - 7:50 pm
SOF
-
ORD
22h 25m
1 stop
LOT Logo
9:50 pm - 1:50 pm
ORD
-
SOF
32h 00m
1 stop
$711LOT
Wed, Sep 9 - Wed, Sep 30
LOT Logo
6:45 pm - 7:50 pm
SOF
-
ORD
33h 05m
1 stop
LOT Logo
5:10 pm - 1:50 pm
ORD
-
SOF
12h 40m
1 stop
$712LOT
Thu, Sep 17 - Sat, Oct 3
LOT Logo
5:25 am - 7:50 pm
SOF
-
ORD
22h 25m
1 stop
LOT Logo
9:50 pm - 1:55 am
ORD
-
SOF
20h 05m
1 stop
$720LOT
Wed, Sep 23 - Wed, Oct 14
LOT Logo
5:25 am - 7:50 pm
SOF
-
ORD
22h 25m
1 stop
LOT Logo
9:50 pm - 1:50 pm
ORD
-
SOF
32h 00m
1 stop
$721LOT
Wed, Sep 9 - Wed, Sep 30
LOT Logo
6:45 pm - 3:05 pm
SOF
-
ORD
28h 20m
2 stops
LOT Logo
5:10 pm - 6:00 pm
ORD
-
SOF
16h 50m
1 stop
$722LOT
Thu, Sep 17 - Sat, Oct 3
KLM Logo
7:00 am - 6:33 pm
SOF
-
MDW
19h 33m
2 stops
KLM Logo
11:25 am - 2:00 pm
MDW
-
SOF
18h 35m
2 stops
$777KLM
Mon, Jul 27 - Wed, Aug 26
Multiple Airlines Logo
7:00 am - 6:18 pm
SOF
-
MDW
19h 18m
2 stops
Multiple Airlines Logo
1:27 pm - 2:00 pm
MDW
-
SOF
16h 33m
2 stops
$930Multiple Airlines
Mon, Jul 27 - Thu, Aug 27
KLM Logo
7:00 am - 6:18 pm
SOF
-
MDW
19h 18m
2 stops
KLM Logo
1:27 pm - 2:00 pm
MDW
-
SOF
16h 33m
2 stops
$935KLM
Sat, Jul 18 - Sat, Aug 1
KLM Logo
7:00 am - 6:07 pm
SOF
-
MDW
19h 07m
2 stops
KLM Logo
1:18 pm - 2:00 pm
MDW
-
SOF
16h 42m
2 stops
$1,009KLM
Booking Insights

KAYAK's insights & trends for Sofia to Illinois flights

Get data-powered insights and trends into flights from Sofia to Illinois to help you find the cheapest flights, the best time to fly and much more.

How much is a round-trip flight from Sofia to Illinois?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from Sofia to Illinois departing in September.

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Sofia to Illinois, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Sofia to Illinois is January, when tickets cost $388 (return) on average. On the other hand, the most expensive months are July and April, when the average cost of round-trip tickets is $674 and $654 respectively.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Sofia to Illinois, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from Sofia to Illinois, you should book around 5 weeks before departure, which saves you about 12% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 5 weeks before departure.

Good to know

Low seasonJanuary
Cheapest flight$358
Best time to beat the crowds with an average 5% drop in price.
Most popular time to fly and prices are also 11% lower on average.
Flight from Sofia to Chicago O'Hare Airport

FAQs - booking Illinois flights

  • How does KAYAK find such low prices on flights from Sofia to Illinois?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Sofia to Illinois.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Sofia to Illinois?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from Sofia to Illinois is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Sofia to Illinois?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly from Sofia to Illinois with an airline and back with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Sofia to Illinois?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying from Sofia to Illinois up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top 5 airlines serving from Sofia to Illinois

 
See real verified KAYAK customer reviews for airlines flying from Sofia to Illinois. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Sofia to Illinois? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.8
KLMOverall score based on 1528 reviews
7.8Boarding
7.2Entertainment
7.3Food
8.4Crew
7.7Comfort
Airline reviews

As always, it’s a pleasure to travel with KLM. It is one of my favorite airlines.

10.0 ExcellentGeorge, May 2026
OTP - AMS
Read more KLM reviews

As always, it’s a pleasure to travel with KLM. It is one of my favorite airlines.

Brand new plane lots of room the snack was very flavourful and enjoyable

As per usual when you Hit the UK it's a slow process through customs Not as efficient at Thailand for sure

The flight was delayed. The aircraft was unclean. Promised seat was not given due to change in Aircraft. Not one crew on ground was in a position to give any response. Amsterdam Airport is AVIODABLE Over crowded. Over Expensive. Poor Services.

Crew is not the cheerful type. very slow meal service (this is their style as have flown this many times)

Empty seats next to me - wish it had been for a longer flight!!

Delay and had to run between flight to get my connection due to this delay but besides that the overall experience was ok. I arrived with just an hour of delay.

Flight was ok but lack of communication cost me to literally beg to be put on another flight as connecting flight had departed

Couldn’t get boarding pass in SLC even with help from a redcoat, so had to find a desk in AMS to get boarding pass. Technical problems so not sure why. Very inconvenient. The KLM app is not as user friendly as most apps. Also had to wait almost an hour on the tarmac for a fuel truck, which caused us to miss a connecting bus in LUX.

The immigration hall in Amsterdam was understaffed, so passport checking was slower than it should be for a major airport. They need to get the automatic readers up and running for non EU passport holders. Waiting in line after a long flight feels a bit abusive.

Issue with boarding, group of passengers on a religious trip coming back to NYC kept trying to change seats, even standing when the plane was pushing back. Crew/Pilot kept very good composure, some passengers got aggravated and started venting out loud but this group created a serious security risk. Crew/Pilot should've been more stringent and called in security or remove them from the flight.

Amazing crew, delicious food and drink selection. 12hr felt more like a 4hrs. Comfortable beds. Can’t wait for the new business class cabin

Flying business class saves you. Once you get out of the terminal and onto the plane, it’s fine. The traffic at the gate is a horror. No organization at all. The fact that Business class is promised early boarding is a myth.

Every time I fly LOT, I swear I will never do it again. And changing planes in Warsaw is a horror. Not even remotely organized. I can only feel sorry for the staff who have to put up with it.

I have flown over 2million miles. Great flight but bizarre boarding process. They must have paged half the passengers to the desk for documentation check before boarding anyone. Overall great value.

The seat was paid for but given for some different person .

Good in general, but i think the chair is not comfortable for traveling more than 2 hours ..

Krakow airport is very disorganized. nice seats. friendly crew. long legs had screens. short leg did not

Horrible communication, flight boarded then we sat on plane for almost 5 hours as the runway was barely covered in snow with no plows in sight and the as we tried to taxi there was a major equipment failure due to poor push off technique causing all passengers to be taken off the flight to ultimately have the flight cancelled. There was barely any communication to passengers as to what was happening or what to do next to get placed on another flight. Arriving to my final destination a whole day later having to take a connecting flight through Lisbon to ultimately end up in New York instead of a direct flight as none available for the next day. Never flying LOT airlines again!

Boarding was a madhouse. Airport staff was completely disinterested in communicating about the delays. Never again.

Older plane with finicky seats. Crew often seem to focus on "pet" clients and over extend services to some over others. I get less attention since I'm not a regular business class client. Regardless, I've paid the money and would expect equal attention.

Our flight attendant was stellar with great anticipation and attention to details. Food was very good, and overall flight, though very long, was really good.

Be honest of what you sell: This was sold as Business Class on all three legs, while the JetBlue plane didn't even have business class seats, and wanted $164 for extra legroom seats.

Great food, and lots of it. They made us come to the gate two hours before the flight and you were stuck in the enclosure until you boarded with no bathroom or food or drink. My seat in business class was very claustrophobic, I could barely get into it and a large board blocked the window and made it even more claustrophobic

Turkish Business Class is a wonderful experience, and the best inflight dining experience I’ve had to date.

The crew was amazing and the food was really good too

Some of the best service I’ve ever seen on an international flight! The staff were super friendly and accommodating. The food was excellent with lots of choices and attention to detail. The seats are kind of old and narrow, but I have wide shoulders. The only area for improvement was making the cabin a little cooler.

It was fantastic. I really enjoyed it. It’s comfortable the flight attendant. Respect you anything you ask for they gave you except the water.

We were experiencing delayed for 4 hours and of course they took us to Turkish airlines lounge but we could not rested up since there is no bedroom. It was tiring and long day for us🙏 Especially we didn’t fly until 5:45am morning for Miami🙏😢

On Turkish it is all about the food and the service. I am overwhelmed with the quality and variety of the dining service offered on business class. I prefer the updated A350 to the older B777 cabin layout, but both are comfortable. Flights left and arrived on time with updates from the captain. I will definitely fly with them again.

Over 5 hour delay with minimal updates or ability to standby for alternative flights. During boarding and 1 hr+ wait for takeoff, seats were drenched w water from air conditioning condensation and always leftover crumbs on carpet and seats

I flew from Barcelona to Chicago on UA yesterday. The flight was on time, the pilots did a great job and the flight attendants were super nice. All of them. Also food was good, and the drinks, including wine were served a few times during our flight. I highly recommend this airline.

Boarded early, left early, arrived 40 mins early! A win win for me!

These airplanes should be illegal. The seats are two tight, it is a safety issue. Wheelchair support was ridiculously slow. We almost missed our flight.

This flight is a quick way to get to Chicago, but a bit expensive.

The clerk at check in for my bags was very rude. My credit card was hacked during my vacation and she told me it was not possible to pay in cash for my bag. “You bought the cheapest ticket, you should have bought a ticket that included a bag. If you cannot pay with a credit card, we will not let you on this flight”. She spoke to her supervisor and then told me , I could ask other passengers, if they would use their credit card to check my bag. I had to beg 5 different people, till one agreed to use their credit card. I payed them cash of course. This was a very stressful and humiliating experience for me. I strongly suggest you build in some kind of provision for travelers who got robbed.

O’hsre taxi and deboarding took 40 minutes. Needed 20 minutes extra time between connecting flights to avoid running through terminal.

Flight crew was super friendly and helpful. Food was frequent and honestly pretty good. Plenty of on-board entertainment. Economy seats are super cramped for such a long flight, but the crew allowed people to get up and stretch, and kids could wander with their parents, so we all made it work. Overall a very good experience.

Standard flight with a drinks and a snack- overall very quick flight. The flight attendants were very strict, bordered on rude.

Starlink is great Crew was polite Business class didn’t get a welcome drink just water and snacks were ok

The legroom was lacking and the entertainment system lacked adequate selection of older films. Modern films are generally not very good.

Perfect airline, super friendly, great service, tasty food. Would fly again.

Original Lufthansa flights were canceled and the alternative route that was offered required cab transfer in New York from JFK to Newark at my own expense. Who can refund these $218?

flight was packed, had to check my carryon bag, tiny snack bag offered, but we arrived on time and thats what counts

Everything could have been better. What needed to be wrong with United went wrong

It was good. The seats in economy weren’t bad

Very good. Comfortable and I felt well taken care of from start to finish

We were in premium economy seats that appeared to be locked in plae, No reclining. My aching back.

I don’t understand how they charge as much as they do for such a poor experience

I wish the plane had pod seating for business class. I had a window seat (8K) and I had to climb over the person sitting on the aisle when I needed to get up. Also there is no partition between the seats for privacy when sleeping. The Asian airlines have much nicer business class seating. Their seats are wider for better comfort when sleeping.

Everything you need to know for your flight from Sofia to Illinois

Information on your arrival and departure airports