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Sofia

$258+ Cheap flights from Boston (BOS) to Sofia (SOF)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 3/15. Fares are subject to change and may not be available on all flights or dates of travel.
BOS — SOF
Mar 7 — Mar 141
Sat 3/7
Sat 3/14
1 adult, Economy
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Cheap flight deals from Boston to Sofia

Cheapest flights from Boston to Sofia
Explore the most affordable flight options available from Boston to Sofia. Find the lowest fares from popular airlines and budget airlines, with prices last updated on February 5, 2026.

This Kiwi.com deal was found by Cheapflights users on 2/5. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/99:40 pm
BOS
-
SOF
1 stop19h 05m
Multiple Airlines
Mon 3/236:45 pm
SOF
-
BOS
1 stop26h 20m
Multiple Airlines
Deal found 2/5$350
This Kiwi.com deal was found by Cheapflights users on 2/2. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/32:20 pm
BOS
-
SOF
2 stops20h 40m
Austrian Airlines
Tue 6/26:55 pm
SOF
-
BOS
1 stop25h 55m
Austrian Airlines
Deal found 2/2$351
This Kiwi.com deal was found by Cheapflights users on 2/3. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/2510:50 pm
BOS
-
SOF
1 stop10h 25m
Multiple Airlines
Wed 4/88:00 am
SOF
-
BOS
2 stops17h 19m
Multiple Airlines
Deal found 2/3$352
This Kiwi.com deal was found by Cheapflights users on 2/2. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/246:25 pm
BOS
-
SOF
1 stop22h 30m
Austrian Airlines
Tue 3/107:55 am
SOF
-
BOS
1 stop13h 10m
Austrian Airlines
Deal found 2/2$353
This Kiwi.com deal was found by Cheapflights users on 2/3. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 2/258:40 pm
BOS
-
SOF
1 stop19h 05m
Lufthansa
Wed 3/112:00 pm
SOF
-
BOS
1 stop11h 35m
Lufthansa
Deal found 2/3$355
This Kiwi.com deal was found by Cheapflights users on 2/5. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/2510:50 pm
BOS
-
SOF
1 stop10h 25m
Multiple Airlines
Wed 4/158:00 am
SOF
-
BOS
1 stop12h 50m
Multiple Airlines
Deal found 2/5$363
This Kiwi.com deal was found by Cheapflights users on 2/2. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/249:50 pm
BOS
-
SOF
2 stops13h 30m
Multiple Airlines
Tue 3/107:55 am
SOF
-
BOS
1 stop13h 10m
Multiple Airlines
Deal found 2/2$372
This Kiwi.com deal was found by Cheapflights users on 2/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/305:20 pm
BOS
-
SOF
1 stop11h 55m
Multiple Airlines
Mon 4/137:25 pm
SOF
-
BOS
1 stop29h 15m
Multiple Airlines
Deal found 2/4$374

Find flight deals from Boston to Sofia

Discover tips and strategies to find the most affordable flight options for your journey from Boston (BOS) 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 February 5, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$350
(Kiwi.com)

One-way from

$258
(Kiwi.com)

Popular in

June

Cheapest in

February

Average price

$461
Provider with most accurate pricing for Boston Logan Intl-Sofia flight deals.
Search Deals
Provider most trusted by Cheapflights users for Boston Logan Intl-Sofia flights.
Search Deals
From Boston Logan Intl to Sofia
Search Deals
One-way flight from Boston Logan Intl to Sofia
Search Deals
Highest demand for flights based on searches. 19% potential increase in price ($160 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($22 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in February 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Boston 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 February 5, 2026.
Use the filters below to find and compare flights from Boston to Sofia that are best for you.

Fly from

Boston

Fly to

Sofia

Route

Depart

Return

Price

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Wed 4/22

5:20 pm-10:20 am

1 stop10h 00m

Sofia

Tue 5/12

1:05 pm-3:10 pm

1 stop33h 05m

$391

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Sun 4/19

8:05 pm-11:10 pm

1 stop20h 05m

Sofia

Tue 5/12

6:10 am-5:40 pm

1 stop18h 30m

$397

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Tue 5/5

5:10 am-12:10 pm

2 stops24h 00m

Sofia

Tue 5/12

12:55 pm-5:40 pm

1 stop11h 45m

$406

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Wed 4/22

8:05 pm-11:10 pm

1 stop20h 05m

Sofia

Mon 5/11

7:25 pm-5:40 pm

1 stop29h 15m

$408

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Mon 4/20

8:05 pm-11:10 pm

1 stop20h 05m

Sofia

Mon 5/11

7:25 pm-5:40 pm

1 stop29h 15m

$408

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Wed 5/6

5:45 am-12:10 pm

2 stops23h 25m

Sofia

Wed 5/13

6:10 am-5:59 pm

2 stops18h 49m

$410

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Mon 5/4

9:40 pm-10:20 am

1 stop29h 40m

Sofia

Tue 5/19

1:05 pm-3:10 pm

1 stop33h 05m

$415

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Mon 5/11

8:05 pm-11:10 pm

1 stop20h 05m

Sofia

Wed 5/27

6:10 am-5:40 pm

1 stop18h 30m

$422

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Mon 5/11

8:05 pm-11:10 pm

1 stop20h 05m

Sofia

Thu 5/28

6:10 am-5:40 pm

1 stop18h 30m

$422

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Mon 5/11

8:05 pm-11:10 pm

1 stop20h 05m

Sofia

Fri 5/29

6:10 am-5:40 pm

1 stop18h 30m

$422

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/2

Showing 1-10 of 18 results
1
2

Compare providers for flights from Boston 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 Boston to Sofia in February.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
OvagoPrice Accuracy2 starsTrust Score*3 stars
AranGrantPrice Accuracy2 starsTrust Score*2 stars
MytripPrice Accuracy3 starsTrust Score*3 stars
Trip.comPrice Accuracy1 starTrust 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 Boston-Sofia flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Boston-Sofia flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Boston-Sofia flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Boston-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 Boston-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 Boston to Sofia

Have a flexible travel schedule? Discover the best time to fly to Sofia from Boston 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 Boston to Sofia

How far ahead should I book a flight from Boston to Sofia?

Use this chart to determine the optimal time to book a round-trip flight from Boston to Sofia. Price data was last updated on January 30, 2026.

The best time to book flights from Boston to Sofia is 60 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 Boston to Sofia?

Currently, April is the cheapest month in which you can book a flight from Boston to Sofia (average of $384). Flying from Boston to Sofia in May is currently the most expensive (average of $630). 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.

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 February 5, 2026.
Peruse reviews from past customers who have flown with KLM, SWISS, and United Airlines from Boston to Sofia to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
KLM
7.7
Good
1,449 reviews

Entertainment

7.1

Food

7.3

Boarding

7.8

Comfort

7.6

Crew

8.4

Overall

7.7

Reviews

1 / 20
10.0
Excellent

Snapyou,Jan 2026

TPA - LHR

Flight operated by Virgin Atlantic - usual high standard service by Virgin.
KLM
7.7
Good
1,449 reviews
KLM
7.7
Good
1,449 reviews

Entertainment

7.1

Food

7.3

Boarding

7.8

Comfort

7.6

Crew

8.4

Overall

7.7

Reviews

1 / 20
10.0
Excellent

Snapyou,Jan 2026

TPA - LHR

Flight operated by Virgin Atlantic - usual high standard service by Virgin.
SWISS
7.6
Good
1,865 reviews
KLM
7.7
Good
1,449 reviews

Entertainment

7.1

Food

7.3

Boarding

7.8

Comfort

7.6

Crew

8.4

Overall

7.7

Reviews

1 / 20
10.0
Excellent

Snapyou,Jan 2026

TPA - LHR

Flight operated by Virgin Atlantic - usual high standard service by Virgin.
United Airlines
7.4
Good
9,241 reviews
KLM
7.7
Good
1,449 reviews

Entertainment

7.1

Food

7.3

Boarding

7.8

Comfort

7.6

Crew

8.4

Overall

7.7

Reviews

1 / 20
10.0
Excellent

Snapyou,Jan 2026

TPA - LHR

Flight operated by Virgin Atlantic - usual high standard service by Virgin.
Turkish Airlines
7.3
Good
4,210 reviews
KLM
7.7
Good
1,449 reviews

Entertainment

7.1

Food

7.3

Boarding

7.8

Comfort

7.6

Crew

8.4

Overall

7.7

Reviews

1 / 20
10.0
Excellent

Snapyou,Jan 2026

TPA - LHR

Flight operated by Virgin Atlantic - usual high standard service by Virgin.
Lufthansa
6.8
Okay
7,762 reviews
KLM
7.7
Good
1,449 reviews

Entertainment

7.1

Food

7.3

Boarding

7.8

Comfort

7.6

Crew

8.4

Overall

7.7

Reviews

1 / 20
10.0
Excellent

Snapyou,Jan 2026

TPA - LHR

Flight operated by Virgin Atlantic - usual high standard service by Virgin.

Related info for your journey

Find useful and relevant information for your journey from Boston 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 Boston to Sofia?

    SWISS, United Airlines, and Lufthansa can get you from Boston to Sofia in just under 10h. Your travel time can differ by up to 10h 05m. The distance between Boston and Sofia is about 4521 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 Boston to Sofia round-trip?

    KLM, at $380, was found to be the cheapest airline from Boston to Sofia.Alternate airlines to your destination round-trip include Austrian Airlines and Air France. KLM is 42% cheaper than the average price of flights available within the next 90 days to this destination.

  • What are the cheapest airlines to fly from Boston to Sofia one-way?

    One-way options have recently been found by users for as low as $229 on Austrian Airlines. Other airlines that offer cheap prices include Lufthansa from $374 and KLM from $385 one-way.

  • Can I find deals for flights from Boston to Sofia that include hotel bookings?

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

  • How can I find direct flights from Boston to Sofia?

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

  • Can I find deals for business class flights from Boston to Sofia?

    Yes. Cheapflights offers flight deals from Boston 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 Boston to Sofia?

    Currently, April is the cheapest month in which you can book a flight from Boston to Sofia (average of $384). Flying from Boston to Sofia in May is currently the most expensive (average of $630). 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

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Boston to Sofia

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

Top 9 airlines flying from Boston to Sofia

Discover the top 9 airlines that operate flights from Boston 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 February 5, 2026.
AirlineCheapestAverageFlexibilityOn-time
KLMCheapest$380Average$548FlexibilityNo cancel feeOn-time75%
Austrian AirlinesCheapest$394Average$687FlexibilityNo cancel feeOn-time78%
Air FranceCheapest$396Average$494FlexibilityNo cancel feeOn-time77%
SWISSCheapest$410Average$685FlexibilityNo cancel feeOn-time79%
United AirlinesCheapest$422Average$708FlexibilityNo cancel feeOn-time69%
LufthansaCheapest$436Average$804FlexibilityNo cancel feeOn-time76%
British AirwaysCheapest$482Average$540FlexibilityNo cancel feeOn-time70%
ITA AirwaysCheapest$505Average$924FlexibilityNo cancel feeOn-time81%
Turkish AirlinesCheapest$535Average$715FlexibilityNo cancel feeOn-time77%

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