$359 Cheap United flights Chicago (ORD) to Sofia (SOF)

View $359 flight on Tue, Aug 26, 2025Opens in a new window

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$359 Cheap United flights Chicago (ORD) to Sofia (SOF)

Prices were available within the past 7 days and start at $359 for one-way flights and $521 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

United
Sun, Sep 28 - Tue, Oct 14
ORD
Chicago
SOF
Sofia
$521 Roundtrip, found 4 days ago
$521
Roundtrip
found 4 days ago
Select United flight, departing Sun, Sep 28 from Chicago to Sofia, returning Tue, Oct 14, priced at $521 found 4 days ago
United
Sun, Sep 21 - Tue, Oct 14
ORD
Chicago
SOF
Sofia
$523 Roundtrip, found 2 hours ago
$523
Roundtrip
found 2 hours ago
Select United flight, departing Sun, Sep 21 from Chicago to Sofia, returning Tue, Oct 14, priced at $523 found 2 hours ago
United
Mon, Sep 15 - Thu, Oct 2
ORD
Chicago
SOF
Sofia
$527 Roundtrip, found 5 days ago
$527
Roundtrip
found 5 days ago
Select United flight, departing Mon, Sep 15 from Chicago to Sofia, returning Thu, Oct 2, priced at $527 found 5 days ago
United
Sun, Sep 21 - Thu, Oct 2
ORD
Chicago
SOF
Sofia
$527 Roundtrip, found 4 days ago
$527
Roundtrip
found 4 days ago
Select United flight, departing Sun, Sep 21 from Chicago to Sofia, returning Thu, Oct 2, priced at $527 found 4 days ago
United
Sun, Sep 21 - Tue, Oct 7
ORD
Chicago
SOF
Sofia
$528 Roundtrip, found 5 hours ago
$528
Roundtrip
found 5 hours ago
Select United flight, departing Sun, Sep 21 from Chicago to Sofia, returning Tue, Oct 7, priced at $528 found 5 hours ago
United
Sun, Dec 14 - Tue, Dec 30
ORD
Chicago
SOF
Sofia
$545 Roundtrip, found 2 days ago
$545
Roundtrip
found 2 days ago
Select United flight, departing Sun, Dec 14 from Chicago to Sofia, returning Tue, Dec 30, priced at $545 found 2 days ago
United
Sun, Sep 28 - Tue, Oct 7
ORD
Chicago
SOF
Sofia
$546 Roundtrip, found 4 days ago
$546
Roundtrip
found 4 days ago
Select United flight, departing Sun, Sep 28 from Chicago to Sofia, returning Tue, Oct 7, priced at $546 found 4 days ago
United
Sun, Sep 21 - Wed, Oct 1
ORD
Chicago
SOF
Sofia
$547 Roundtrip, found 1 day ago
$547
Roundtrip
found 1 day ago
Select United flight, departing Sun, Sep 21 from Chicago to Sofia, returning Wed, Oct 1, priced at $547 found 1 day ago
United
Tue, Dec 16 - Tue, Dec 30
ORD
Chicago
SOF
Sofia
$551 Roundtrip, found 2 days ago
$551
Roundtrip
found 2 days ago
Select United flight, departing Tue, Dec 16 from Chicago to Sofia, returning Tue, Dec 30, priced at $551 found 2 days ago
United
Sun, Sep 21 - Fri, Oct 10
ORD
Chicago
SOF
Sofia
$553 Roundtrip, found 2 hours ago
$553
Roundtrip
found 2 hours ago
Select United flight, departing Sun, Sep 21 from Chicago to Sofia, returning Fri, Oct 10, priced at $553 found 2 hours ago
Flights from Chicago (ORD) to Sofia (SOF)
Origin airport
O'Hare Intl.
Destination airport
Sofia
Airlines serving
Air Canada, Air France, Air Serbia, American Airlines, Austrian Airlines, British Airways, Emirates, ITA Airways, Iberia, JetBlue Airways, KLM, LOT-Polish Airlines, Lufthansa, Swiss International Air Lines, TAP Portugal, Turkish Airlines, United
Popular airline
Lufthansa
Distance
5197 mi

Frequently asked questions

How much is a United Airlines flight from O'Hare Intl. Airport (ORD) to Sofia Airport (SOF)?
You can discover cheap return United Airlines flights from $521 from ORD to SOF by sorting your results from "Price (lowest to highest)" on Expedia. Or look for bargains from $359 for a one-way trip.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.
What is the cheapest month to fly from ORD to SOF with United Airlines?
Search for one-way or return flights to Sofia in January or February. You could find an affordable fare with United Airlines during these off-season months.
What is the cheapest time to book flights from O'Hare Intl. Airport (ORD) to Sofia Airport (SOF) with United Airlines?
Check for United Airlines flights from ORD to SOF about one month before you want to leave. The most affordable time to book an international flight is generally 18 to 29 days ahead of your travel date when you can save 17% versus booking four to five months in advance. Regardless of fare class or itinerary, the best day to book international airfare is usually Sunday. Friday can be the most expensive. Passengers booking on a Sunday can save 17% on average compared to those who book on a Friday.**Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC's global airline sales database.
Does United Airlines fly nonstop from O'Hare Intl. Airport (ORD) to Sofia Airport (SOF)?
To see if there's a direct trip from ORD to SOF with United Airlines or any other carriers, check the "Nonstop" filter when looking for tickets.
What is the earliest United Airlines flight from ORD to SOF?
Search United Airlines's earliest flights from ORD to SOF by using our "Morning" and "Early Morning" filters. Not only will you get to your destination sooner, early departures are also 20% less likely to be canceled.**Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
What airports does United Airlines fly into in Sofia?
United Airlines flights from O'Hare Intl. Airport (ORD) to Sofia come in to land at Sofia Airport (SOF). This is the main entry point here.
Why fly with United Airlines from ORD to SOF?
A rewarding loyalty program and the ability to rack up points through United Mileage Plus are the start of the reasons to depart from ORD to SOF with United Airlines. Plus, when you sign up to our One Key™ program, you can earn OneKeyCash™* in addition to any airline loyalty program earnings. It's yours to spend on future travel plans.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.
Can I change or cancel my United Airlines flight from O'Hare Intl. Airport (ORD) to Sofia Airport (SOF)?
It's generally possible to cancel or change your flight, although additional charges may apply if your booking was made over 24 hours ago. Want to keep your options open? Use Expedia's "Changes included" or "No cancel fee" filter to find flights that won't penalize you if you need to adjust your plans. To update your itinerary, visit "Trips," select your flight and click on "Manage Booking" for more details.

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