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Sofia

$732+ 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 9/5. Fares are subject to change and may not be available on all flights or dates of travel.
STL — SOF
Jun 17 — Jun 241
Tue 6/17
Tue 6/24
1 adult, Economy
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Cheapflights Tip: The best prices from Lambert-St Louis to Sofia are usually found in February or January, booked 22 days in advance, depart on a Saturday or Sunday and return on a Tuesday

Cheap 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 June 12, 2025.

Round-trip from

$732
(United Airlines)

Popular in

June

Cheapest in

February

Average price

$1,434
From Lambert-St Louis to Sofia
Search Deals
Highest demand for flights based on searches. 11% potential increase in price ($135 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($37 potential savings vs. average RT price).
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Average for round-trip flights in June 2025
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Find 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 June 12, 2025.

This United Airlines deal was found by Cheapflights users on 6/10. 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.
Fri 9/51:30 pmSTL - SOF
2 stops25h 20mUnited Airlines
Fri 9/196:15 amSOF - STL
1 stop15h 15mUnited Airlines
Deal found 6/10$732
This Justfly.com deal was found by Cheapflights users on 6/10. 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.
Fri 9/55:30 pmSTL - SOF
2 stops21h 20mMultiple Airlines
Fri 9/196:15 amSOF - STL
2 stops21h 42mMultiple Airlines
Deal found 6/10$736
This CrystalTravel deal was found by Cheapflights users on 6/10. 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 CrystalTravel is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/53:30 pmSTL - SOF
1 stop13h 55mLufthansa
Fri 9/196:15 amSOF - STL
1 stop15h 15mLufthansa
Deal found 6/10$883
This Orbitz deal was found by Cheapflights users on 6/12. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/2111:14 amSTL - SOF
2 stops21h 06mBritish Airways
Sat 12/2712:05 pmSOF - STL
2 stops41h 57mBritish Airways
Deal found 6/12$1,022
This oojo deal was found by Cheapflights users on 6/10. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/188:10 amSTL - SOF
2 stops22h 35mTurkish Airlines
Wed 7/23:35 pmSOF - STL
2 stops39h 10mTurkish Airlines
Deal found 6/10$1,876
This Air Canada deal was found by Cheapflights users on 6/12. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/214:15 pmSTL - SOF
2 stops17h 50mAir Canada
Sat 12/276:15 amSOF - STL
3 stops22h 49mAir Canada
Deal found 6/12$2,281

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 June 12, 2025.
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

Fri 9/5

1:30 pm-10:50 pm

2 stops25h 20m

Sofia

Fri 9/19

6:15 am-1:30 pm

1 stop15h 15m

$732

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Fri 9/5

5:30 pm-10:50 pm

2 stops21h 20m

Sofia

Fri 9/19

6:15 am-7:57 pm

2 stops21h 42m

$736

St. LouisSofia

STL - SOF

STLSOF

Lambert-St Louis

Fri 9/5

3:30 pm-1:25 pm

1 stop13h 55m

Sofia

Fri 9/19

6:15 am-1:30 pm

1 stop15h 15m

$883

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/10

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 June 9, 2025.

The best time to book flights from St. Louis to Sofia is 22 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.

What is the cheapest month to book a flight from St. Louis to Sofia?

Currently, November is the cheapest month in which you can book a flight from St. Louis to Sofia (average of $632). Flying from St. Louis to Sofia in June is currently the most expensive (average of $1,203). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

Rainfall in Sofia by month

Plan your trip to Sofia by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Sofia ranges from 1.2 - 2.8 inches per month. June is typically the wettest month, when rainfall can reach 2.8 in. January is typically the driest time to visit Sofia when rainfall is around 1.2 in.

Temperature in Sofia by month

Plan your trip to Sofia by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Sofia, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 68.0 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 30.2 F).

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 June 12, 2025.
Read reviews from past customers who have flown United Airlines and Lufthansa from St. Louis to Sofia. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
8,790 reviews

Entertainment

7.0

Boarding

7.7

Comfort

7.3

Food

6.6

Overall

7.4

Crew

8.1

Reviews

1 / 20
4.0
Okay

Thomas,Mar 2025

SFO - TPE

When I asked for an extra snack, I got an unhappy look from the stewardess. Geez, does one extra snack really affect the bottom line??
United Airlines
7.4
Good
8,790 reviews
United Airlines
7.4
Good
8,790 reviews

Entertainment

7.0

Boarding

7.7

Comfort

7.3

Food

6.6

Overall

7.4

Crew

8.1

Reviews

1 / 20
4.0
Okay

Thomas,Mar 2025

SFO - TPE

When I asked for an extra snack, I got an unhappy look from the stewardess. Geez, does one extra snack really affect the bottom line??
Lufthansa
6.8
Okay
7,136 reviews
United Airlines
7.4
Good
8,790 reviews

Entertainment

7.0

Boarding

7.7

Comfort

7.3

Food

6.6

Overall

7.4

Crew

8.1

Reviews

1 / 20
4.0
Okay

Thomas,Mar 2025

SFO - TPE

When I asked for an extra snack, I got an unhappy look from the stewardess. Geez, does one extra snack really affect the bottom line??

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.

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

    United Airlines, at $732, 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 29% 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.

  • What is the cheapest month to book a flight from St. Louis to Sofia?

    Currently, November is the cheapest month in which you can book a flight from St. Louis to Sofia (average of $632). Flying from St. Louis to Sofia in June is currently the most expensive (average of $1,203). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

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 June 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$711Average$966FlexibilityNo cancel feeOn-time69%
LufthansaCheapest$725Average$1,020FlexibilityNo cancel feeOn-time76%

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