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$256+ 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 3/19. Fares are subject to change and may not be available on all flights or dates of travel.
BOS — SOF
Feb 5 — Feb 121
Thu 2/5
Thu 2/12
1 adult, Economy
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Cheap 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 January 6, 2026.

Most accurate provider

Mytrip
3 stars

Most trusted provider

Mytrip
3 stars

Round-trip from

$339
(Kiwi.com)

One-way from

$256
(oojo)

Popular in

June

Cheapest in

November

Average price

$561
Provider with most accurate pricing for Boston Logan Intl-Sofia flight deals.
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Provider most trusted by Cheapflights users for Boston Logan Intl-Sofia flights.
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From Boston Logan Intl to Sofia
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One-way flight from Boston Logan Intl to Sofia
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Highest demand for flights based on searches. 17% potential increase in price ($142 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($20 potential savings vs. average RT price).
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Average for round-trip flights in January 2026
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Find 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 January 6, 2026.

This Kiwi.com deal was found by Cheapflights users on 1/5. 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.
Tue 1/272:20 pmBOS - SOF
2 stops15h 55mLufthansa
Tue 2/102:00 pmSOF - BOS
1 stop11h 35mLufthansa
Deal found 1/5$339
This Kiwi.com deal was found by Cheapflights users on 1/6. 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 2/32:20 pmBOS - SOF
2 stops15h 55mLufthansa
Tue 2/102:00 pmSOF - BOS
1 stop11h 35mLufthansa
Deal found 1/6$340
This Kiwi.com deal was found by Cheapflights users on 1/6. 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 1/288:40 pmBOS - SOF
1 stop14h 40mLufthansa
Wed 2/112:00 pmSOF - BOS
1 stop11h 35mLufthansa
Deal found 1/6$354
This Kiwi.com deal was found by Cheapflights users on 1/6. 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 4/75:10 pmBOS - SOF
1 stop11h 30mAustrian Airlines
Tue 4/216:55 pmSOF - BOS
1 stop25h 55mAustrian Airlines
Deal found 1/6$357
This Mytrip deal was found by Cheapflights users on 1/6. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 1/283:40 pmBOS - SOF
2 stops14h 35mMultiple Airlines
Wed 2/112:00 pmSOF - BOS
1 stop11h 35mMultiple Airlines
Deal found 1/6$375
This Mytrip deal was found by Cheapflights users on 1/6. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 2/13:35 pmBOS - SOF
2 stops13h 15mMultiple Airlines
Mon 2/166:45 pmSOF - BOS
1 stop26h 20mMultiple Airlines
Deal found 1/6$377
This FlightHub deal was found by Cheapflights users on 1/6. 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.
Tue 1/272:20 pmBOS - SOF
2 stops15h 55mMultiple Airlines
Tue 2/102:15 pmSOF - BOS
2 stops26h 47mMultiple Airlines
Deal found 1/6$378
This Mytrip deal was found by Cheapflights users on 1/6. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/710:45 amBOS - SOF
2 stops18h 25mMultiple Airlines
Tue 4/2112:55 pmSOF - BOS
1 stop11h 45mMultiple Airlines
Deal found 1/6$379
This FlightHub deal was found by Cheapflights users on 1/6. 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.
Tue 1/272:20 pmBOS - SOF
2 stops15h 55mMultiple Airlines
Tue 2/37:55 amSOF - BOS
2 stops18h 47mMultiple Airlines
Deal found 1/6$385

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 January 6, 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

Tue 1/27

7:10 pm-2:05 pm

1 stop11h 55m

Sofia

Tue 2/3

7:10 am-1:40 pm

1 stop13h 30m

$410

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Tue 2/3

7:10 pm-2:05 pm

1 stop11h 55m

Sofia

Tue 2/10

7:10 am-1:40 pm

1 stop13h 30m

$410

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Tue 1/27

7:10 pm-2:05 pm

1 stop11h 55m

Sofia

Tue 2/10

7:10 am-1:40 pm

1 stop13h 30m

$410

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Wed 4/15

5:30 am-10:20 am

2 stops21h 50m

Sofia

Sat 4/25

6:10 am-6:01 pm

2 stops18h 51m

$456

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Fri 2/20

9:45 am-1:15 pm

2 stops20h 30m

Sofia

Fri 2/27

7:55 am-7:37 pm

2 stops18h 42m

$459

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Fri 2/6

9:30 am-10:45 pm

2 stops30h 15m

Sofia

Fri 2/20

7:55 am-5:21 pm

2 stops16h 26m

$459

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Wed 4/15

1:00 pm-12:10 pm

2 stops16h 10m

Sofia

Sun 4/26

6:10 am-12:11 pm

2 stops37h 01m

$463

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Fri 2/6

4:15 pm-1:35 pm

1 stop14h 20m

Sofia

Tue 2/10

2:00 pm-6:35 pm

1 stop11h 35m

$469

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Sat 2/28

4:25 pm-6:20 pm

2 stops42h 55m

Sofia

Sat 3/14

6:25 am-12:12 pm

2 stops35h 47m

$479

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Wed 4/15

10:50 pm-1:25 pm

2 stops31h 35m

$263

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/6

Showing 1-10 of 15 results
1
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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 January.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
OvagoPrice Accuracy2 starsTrust Score*2 stars
AranGrantPrice Accuracy2 starsTrust Score*3 stars
MytripPrice Accuracy3 starsTrust Score*3 stars
Trip.comPrice 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 Boston-Sofia flights, users find the pricing of Mytrip to be most consistent on Cheapflights vs. Mytrip Users can find the same prices on Boston-Sofia flight deals on Cheapflights vs. Mytrip >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 Mytrip the most. Mytrip 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 2, 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, February is the cheapest month in which you can book a flight from Boston to Sofia (average of $386). Flying from Boston to Sofia in May is currently the most expensive (average of $645). 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 January 6, 2026.
Peruse reviews from past customers who have flown with KLM, United Airlines, and Turkish 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
1,434 reviews

Food

7.2

Entertainment

7.1

Comfort

7.6

Boarding

7.8

Overall

7.7

Crew

8.4

Reviews

1 / 20
8.0
Excellent

Anonymous,Dec 2025

YYC - AMS

Not literally sitting in the very last row in the middle
KLM
7.7
Good
1,434 reviews
KLM
7.7
Good
1,434 reviews

Food

7.2

Entertainment

7.1

Comfort

7.6

Boarding

7.8

Overall

7.7

Crew

8.4

Reviews

1 / 20
8.0
Excellent

Anonymous,Dec 2025

YYC - AMS

Not literally sitting in the very last row in the middle
United Airlines
7.4
Good
9,132 reviews
KLM
7.7
Good
1,434 reviews

Food

7.2

Entertainment

7.1

Comfort

7.6

Boarding

7.8

Overall

7.7

Crew

8.4

Reviews

1 / 20
8.0
Excellent

Anonymous,Dec 2025

YYC - AMS

Not literally sitting in the very last row in the middle
Turkish Airlines
7.3
Good
4,150 reviews
KLM
7.7
Good
1,434 reviews

Food

7.2

Entertainment

7.1

Comfort

7.6

Boarding

7.8

Overall

7.7

Crew

8.4

Reviews

1 / 20
8.0
Excellent

Anonymous,Dec 2025

YYC - AMS

Not literally sitting in the very last row in the middle
Lufthansa
6.8
Okay
7,683 reviews
KLM
7.7
Good
1,434 reviews

Food

7.2

Entertainment

7.1

Comfort

7.6

Boarding

7.8

Overall

7.7

Crew

8.4

Reviews

1 / 20
8.0
Excellent

Anonymous,Dec 2025

YYC - AMS

Not literally sitting in the very last row in the middle
British Airways
6.7
Okay
7,657 reviews
KLM
7.7
Good
1,434 reviews

Food

7.2

Entertainment

7.1

Comfort

7.6

Boarding

7.8

Overall

7.7

Crew

8.4

Reviews

1 / 20
8.0
Excellent

Anonymous,Dec 2025

YYC - AMS

Not literally sitting in the very last row in the middle

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?

    United Airlines can get you from Boston to Sofia in just under 20h 30m. Your travel time can differ by up to . The distance between Boston and Sofia is about 4521 mi.

  • 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 44% 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 $288 on Air France. Other airlines that offer cheap prices include Lufthansa from $374 and Austrian Airlines from $409 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, February is the cheapest month in which you can book a flight from Boston to Sofia (average of $386). Flying from Boston to Sofia in May is currently the most expensive (average of $645). 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 January 6, 2026.
AirlineCheapestAverageFlexibilityOn-time
KLMCheapest$380Average$573FlexibilityNo cancel feeOn-time75%
Austrian AirlinesCheapest$394Average$694FlexibilityNo cancel feeOn-time78%
Air FranceCheapest$416Average$495FlexibilityNo cancel feeOn-time77%
SWISSCheapest$417Average$712FlexibilityNo cancel feeOn-time79%
United AirlinesCheapest$422Average$743FlexibilityNo cancel feeOn-time69%
LufthansaCheapest$446Average$844FlexibilityNo cancel feeOn-time76%
British AirwaysCheapest$482Average$540FlexibilityNo cancel feeOn-time70%
ITA AirwaysCheapest$505Average$924FlexibilityNo cancel feeOn-time81%
Turkish AirlinesCheapest$536Average$699FlexibilityNo cancel feeOn-time77%

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