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Sofia

$547+ Cheap flights from St. Louis (STL) to Sofia (SOF)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 2/26. Fares are subject to change and may not be available on all flights or dates of travel.
STL — SOF
Feb 28 — Mar 71
Sat 2/28
Sat 3/7
1 adult, Economy
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Cheap flight deals from St. Louis to Sofia

Cheapest flights from St. Louis to Sofia
Explore the most affordable flight options available from St. Louis to Sofia. Find the lowest fares from popular airlines and budget airlines, with prices last updated on January 29, 2026.

This United Airlines deal was found by Cheapflights users on 1/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/2611:25 am
STL
-
SOF
2 stops27h 20m
United Airlines
Mon 3/26:10 am
SOF
-
STL
2 stops22h 16m
United Airlines
Deal found 1/28$547
This Justfly.com deal was found by Cheapflights users on 1/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 3/16:55 pm
STL
-
SOF
2 stops15h 25m
Multiple Airlines
Sat 3/76:15 pm
SOF
-
STL
2 stops36h 36m
Multiple Airlines
Deal found 1/27$595
This FlightHub deal was found by Cheapflights users on 1/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 3/16:55 pm
STL
-
SOF
2 stops19h 50m
Lufthansa
Sat 3/72:25 pm
SOF
-
STL
1 stop31h 30m
Lufthansa
Deal found 1/27$600
This Gotogate deal was found by Cheapflights users on 1/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/207:30 am
STL
-
SOF
2 stops20h 40m
Multiple Airlines
Wed 5/276:20 am
SOF
-
STL
1 stop15h 05m
Multiple Airlines
Deal found 1/28$687
This United Airlines deal was found by Cheapflights users on 1/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/207:30 am
STL
-
SOF
2 stops31h 20m
United Airlines
Wed 5/276:20 am
SOF
-
STL
2 stops21h 45m
United Airlines
Deal found 1/28$705
This Gurufare deal was found by Cheapflights users on 1/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Gurufare is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/203:30 pm
STL
-
SOF
1 stop13h 55m
Lufthansa
Wed 5/276:20 am
SOF
-
STL
1 stop15h 05m
Lufthansa
Deal found 1/28$997
This Gurufare deal was found by Cheapflights users on 1/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Gurufare is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/18:25 am
STL
-
SOF
2 stops30h 45m
Lufthansa
Tue 8/46:10 am
SOF
-
STL
1 stop15h 15m
Lufthansa
Deal found 1/26$1,019

Find flight deals from St. Louis to Sofia

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Sofia (SOF). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated January 29, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$547
(United Airlines)

Popular in

June

Cheapest in

January

Average price

$528
Provider with most accurate pricing for Lambert-St Louis-Sofia flight deals.
Search Deals
Provider most trusted by Cheapflights users for Lambert-St Louis-Sofia flights.
Search Deals
From Lambert-St Louis to Sofia
Search Deals
Highest demand for flights based on searches. 21% potential increase in price ($244 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 6% potential price decrease ($54 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in January 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from St. Louis 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, Cheapflights users made 2,558,603 searches. Data last updated January 29, 2026.
Use the filters below to find and compare flights from St. Louis to Sofia that are best for you.

Fly from

St. Louis

Fly to

Sofia

Route

Depart

Return

Price

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Thu 2/26

11:25 am-10:45 pm

2 stops27h 20m

Sofia

Mon 3/2

6:10 am-8:26 pm

2 stops22h 16m

$547

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Sun 3/1

6:55 pm-6:20 pm

2 stops15h 25m

Sofia

Sat 3/7

6:15 pm-10:51 pm

2 stops36h 36m

$595

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Sun 3/1

6:55 pm-10:45 pm

2 stops19h 50m

Sofia

Sat 3/7

2:25 pm-1:55 pm

1 stop31h 30m

$600

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Wed 5/20

7:30 am-12:10 pm

2 stops20h 40m

Sofia

Wed 5/27

6:20 am-1:25 pm

1 stop15h 05m

$687

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Wed 5/20

7:30 am-10:50 pm

2 stops31h 20m

Sofia

Wed 5/27

6:20 am-8:05 pm

2 stops21h 45m

$705

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Wed 5/20

3:30 pm-1:25 pm

1 stop13h 55m

Sofia

Wed 5/27

6:20 am-1:25 pm

1 stop15h 05m

$997

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Wed 7/1

8:25 am-11:10 pm

2 stops30h 45m

Sofia

Tue 8/4

6:10 am-1:25 pm

1 stop15h 15m

$1,019

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/28

Compare providers for flights from St. Louis to Sofia

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from St. Louis to Sofia in January.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
AranGrantPrice Accuracy2 starsTrust Score*2 stars
OvagoPrice Accuracy2 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on St. Louis-Sofia flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on St. Louis-Sofia flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from St. Louis-Sofia flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on St. Louis-Sofia flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for St. Louis-Sofia flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from St. Louis to Sofia

Have a flexible travel schedule? Discover the best time to fly to Sofia from St. Louis with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from St. Louis to Sofia

How far ahead should I book a flight from St. Louis to Sofia?

Use this chart to determine the optimal time to book a round-trip flight from St. Louis to Sofia. Price data was last updated on January 23, 2026.

The best time to book flights from St. Louis to Sofia is 48 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

Reviews of airlines servicing Sofia

Get insights into the airlines that provide service to Sofia. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Sofia. Reviews last updated January 29, 2026.
Read through reviews of airlines operating flights from St. Louis to Sofia, such as United Airlines and Lufthansa. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
9,215 reviews

Overall

7.4

Food

6.6

Boarding

7.7

Comfort

7.3

Crew

8.1

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Dane,Jan 2026

TYS - IAD

It was a short flight, so no time for amenities. Just glad everything was quick and easy from boarding to arriving at my destination with my family
United Airlines
7.4
Good
9,215 reviews
United Airlines
7.4
Good
9,215 reviews

Overall

7.4

Food

6.6

Boarding

7.7

Comfort

7.3

Crew

8.1

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Dane,Jan 2026

TYS - IAD

It was a short flight, so no time for amenities. Just glad everything was quick and easy from boarding to arriving at my destination with my family
Lufthansa
6.8
Okay
7,754 reviews
United Airlines
7.4
Good
9,215 reviews

Overall

7.4

Food

6.6

Boarding

7.7

Comfort

7.3

Crew

8.1

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Dane,Jan 2026

TYS - IAD

It was a short flight, so no time for amenities. Just glad everything was quick and easy from boarding to arriving at my destination with my family

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Sofia. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How long is the flight from St. Louis to Sofia?

    For as low as $600, United Airlines can have you in Sofia from St. Louis in 19h 50m. Airlines will cover a distance of 5444 mi. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

  • What are the cheapest airlines flying from St. Louis to Sofia round-trip?

    United Airlines, at $560, was found to be the cheapest airline from St. Louis to Sofia. An alternate airline flying to your destination would be Lufthansa. Users have found that United Airlines is 36% cheaper than the other options available to this destination.

  • Can I find deals for flights from St. Louis to Sofia that include hotel bookings?

    Yes. In addition to deals on St. Louis to Sofia flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from St. Louis to Sofia?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to Sofia.

  • Can I find deals for business class flights from St. Louis to Sofia?

    Yes. Cheapflights offers flight deals from St. Louis to Sofia by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

See more FAQs

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Alternative routes for St. Louis to Sofia

See prices for flight routes from nearby airports that may be better suited for you.
Kansas City to Sofia flights

Top 2 airlines flying from St. Louis to Sofia

Discover the top 2 airlines that operate flights from St. Louis to Sofia. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated January 29, 2026.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$560Average$847FlexibilityNo cancel feeOn-time69%
LufthansaCheapest$614Average$889FlexibilityNo cancel feeOn-time76%

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