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Sofia

$290+ 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 12/11. Fares are subject to change and may not be available on all flights or dates of travel.
BOS — SOF
Dec 21 — Dec 281
Sun 12/21
Sun 12/28
1 adult, Economy
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Cheapflights Tip: The best prices from Boston Logan Intl to Sofia are usually found in October or January, booked 67 days in advance, depart on a Tuesday or Saturday and return on a Thursday

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 November 21, 2025.

This Mytrip deal was found by Cheapflights users on 11/20. 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.
Mon 12/13:40 pmBOS - SOF
2 stops14h 35mMultiple Airlines
Tue 12/167:55 amSOF - BOS
1 stop13h 10mMultiple Airlines
Deal found 11/20$367
This CrystalTravel deal was found by Cheapflights users on 11/20. 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.
Mon 12/18:40 pmBOS - SOF
1 stop19h 05mLufthansa
Tue 12/166:05 amSOF - BOS
1 stop19h 30mLufthansa
Deal found 11/20$377
This FlightHub deal was found by Cheapflights users on 11/20. 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.
Mon 12/87:07 pmBOS - SOF
2 stops20h 38mMultiple Airlines
Mon 12/156:45 pmSOF - BOS
1 stop26h 20mMultiple Airlines
Deal found 11/20$383
This Cheapflightsfares deal was found by Cheapflights users on 11/20. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/22:15 pmBOS - SOF
2 stops14h 35mMultiple Airlines
Wed 12/102:00 pmSOF - BOS
1 stop11h 35mMultiple Airlines
Deal found 11/20$397
This FlightHub deal was found by Cheapflights users on 11/20. 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.
Mon 12/82:15 pmBOS - SOF
2 stops16h 00mLufthansa
Mon 12/157:05 pmSOF - BOS
2 stops30h 43mLufthansa
Deal found 11/20$400
This Lufthansa deal was found by Cheapflights users on 11/19. 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 Lufthansa is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/278:40 pmBOS - SOF
1 stop19h 05mLufthansa
Tue 12/27:05 pmSOF - BOS
1 stop30h 30mLufthansa
Deal found 11/19$452
This KLM deal was found by Cheapflights users on 11/19. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/17:10 pmBOS - SOF
1 stop11h 55mKLM
Sat 2/287:00 amSOF - BOS
1 stop13h 25mKLM
Deal found 11/19$459
This Mytrip deal was found by Cheapflights users on 11/18. 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.
Fri 12/129:20 pmBOS - SOF
1 stop17h 00mMultiple Airlines
Sun 12/1410:30 pmSOF - BOS
1 stop22h 20mMultiple Airlines
Deal found 11/18$461

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 November 21, 2025.

Most accurate provider

Mytrip
3 stars

Most trusted provider

Mytrip
3 stars

Round-trip from

$345
(Kiwi.com)

One-way from

$290
(Kiwi.com)

Popular in

December

Cheapest in

October

Average price

$661
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. 4% potential increase in price ($38 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease ($36 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in November 2025
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 November 21, 2025.
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

Mon 12/8

7:07 pm-10:45 pm

2 stops20h 38m

Sofia

Mon 12/15

6:45 pm-2:05 pm

1 stop26h 20m

$383

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Mon 4/13

8:05 pm-11:10 pm

1 stop20h 05m

Sofia

Wed 4/29

12:50 pm-5:40 pm

1 stop11h 50m

$391

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Tue 3/10

2:15 pm-1:15 pm

2 stops17h 00m

Sofia

Tue 3/31

6:10 am-12:04 am

2 stops24h 54m

$393

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Tue 12/2

2:15 pm-11:50 am

2 stops14h 35m

Sofia

Wed 12/10

2:00 pm-6:35 pm

1 stop11h 35m

$397

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Mon 3/23

9:40 pm-6:20 pm

1 stop14h 40m

Sofia

Mon 4/6

7:25 pm-5:40 pm

1 stop29h 15m

$405

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Tue 1/13

9:30 am-6:20 pm

3 stops25h 50m

Sofia

Tue 1/27

6:00 am-7:42 pm

2 stops20h 42m

$406

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Mon 4/13

6:40 pm-6:00 pm

2 stops40h 20m

Sofia

Wed 4/29

12:50 pm-5:57 pm

2 stops36h 07m

$416

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Thu 4/23

5:30 am-6:40 pm

2 stops30h 10m

Sofia

Thu 5/7

12:50 pm-9:20 pm

2 stops15h 30m

$445

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Thu 2/19

10:15 am-1:15 pm

2 stops20h 00m

Sofia

Thu 3/5

6:05 am-1:10 pm

2 stops14h 05m

$446

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Fri 3/27

6:15 am-6:20 pm

2 stops30h 05m

Sofia

Tue 3/31

12:50 pm-10:38 pm

2 stops16h 48m

$448

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/20

Showing 1-10 of 17 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 November.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
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 November 14, 2025.

The best time to book flights from Boston to Sofia is 67 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, January is the cheapest month in which you can book a flight from Boston to Sofia (average of $394). Flying from Boston to Sofia in May is currently the most expensive (average of $609). 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.

What is the cheapest time of day to fly from BOS to SOF?

Find hourly flight availability from Boston to Sofia. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated November 21, 2025.

When flying from Boston to Sofia, the time of day you fly usually plays a role in the price. Save by searching for a flight in the evening, which can drop the price by up to 20% versus a flight in the morning.

How much does it cost to fly round-trip from Boston to Sofia?

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 November 21, 2025.
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
1,414 reviews

Overall

7.7

Food

7.3

Comfort

7.7

Boarding

7.8

Entertainment

7.1

Crew

8.4

Reviews

1 / 20
2.0
Mediocre

Abisola,Oct 2025

LOS - CDG

The food option was finished and what wa left was vegan pasta so I had to go without food for an 8 hour flight without any sort of empathy from crew that was mean.
KLM
7.7
Good
1,414 reviews
KLM
7.7
Good
1,414 reviews

Overall

7.7

Food

7.3

Comfort

7.7

Boarding

7.8

Entertainment

7.1

Crew

8.4

Reviews

1 / 20
2.0
Mediocre

Abisola,Oct 2025

LOS - CDG

The food option was finished and what wa left was vegan pasta so I had to go without food for an 8 hour flight without any sort of empathy from crew that was mean.
United Airlines
7.4
Good
9,029 reviews
KLM
7.7
Good
1,414 reviews

Overall

7.7

Food

7.3

Comfort

7.7

Boarding

7.8

Entertainment

7.1

Crew

8.4

Reviews

1 / 20
2.0
Mediocre

Abisola,Oct 2025

LOS - CDG

The food option was finished and what wa left was vegan pasta so I had to go without food for an 8 hour flight without any sort of empathy from crew that was mean.
Turkish Airlines
7.3
Good
4,044 reviews
KLM
7.7
Good
1,414 reviews

Overall

7.7

Food

7.3

Comfort

7.7

Boarding

7.8

Entertainment

7.1

Crew

8.4

Reviews

1 / 20
2.0
Mediocre

Abisola,Oct 2025

LOS - CDG

The food option was finished and what wa left was vegan pasta so I had to go without food for an 8 hour flight without any sort of empathy from crew that was mean.
Lufthansa
6.8
Okay
7,579 reviews
KLM
7.7
Good
1,414 reviews

Overall

7.7

Food

7.3

Comfort

7.7

Boarding

7.8

Entertainment

7.1

Crew

8.4

Reviews

1 / 20
2.0
Mediocre

Abisola,Oct 2025

LOS - CDG

The food option was finished and what wa left was vegan pasta so I had to go without food for an 8 hour flight without any sort of empathy from crew that was mean.
British Airways
6.7
Okay
7,533 reviews
KLM
7.7
Good
1,414 reviews

Overall

7.7

Food

7.3

Comfort

7.7

Boarding

7.8

Entertainment

7.1

Crew

8.4

Reviews

1 / 20
2.0
Mediocre

Abisola,Oct 2025

LOS - CDG

The food option was finished and what wa left was vegan pasta so I had to go without food for an 8 hour flight without any sort of empathy from crew that was mean.

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?

    Lufthansa can get you from Boston to Sofia in just under 20h 05m. 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 $407, was found to be the cheapest airline from Boston to Sofia.Alternate airlines to your destination round-trip include Air France and SWISS. KLM is 46% cheaper than the average price of flights available within the next 90 days to this destination.

  • 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, January is the cheapest month in which you can book a flight from Boston to Sofia (average of $394). Flying from Boston to Sofia in May is currently the most expensive (average of $609). 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 November 21, 2025.
AirlineCheapestAverageFlexibilityOn-time
KLMCheapest$407Average$711FlexibilityNo cancel feeOn-time75%
Air FranceCheapest$416Average$566FlexibilityNo cancel feeOn-time77%
SWISSCheapest$436Average$724FlexibilityNo cancel feeOn-time79%
Austrian AirlinesCheapest$447Average$736FlexibilityNo cancel feeOn-time78%
LufthansaCheapest$451Average$863FlexibilityNo cancel feeOn-time76%
United AirlinesCheapest$472Average$803FlexibilityNo cancel feeOn-time69%
ITA AirwaysCheapest$505Average$924FlexibilityNo cancel feeOn-time81%
British AirwaysCheapest$510Average$560FlexibilityNo cancel feeOn-time70%
Turkish AirlinesCheapest$520Average$679FlexibilityNo cancel feeOn-time77%

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