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Sofia

$248+ 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 8/22. Fares are subject to change and may not be available on all flights or dates of travel.
BOS — SOF
Jun 27 — Jul 41
Sat 6/27
Sat 7/4
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 May 28, 2026.

This Kiwi.com deal was found by Cheapflights users on 5/26. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 7/1211:35 pm
BOS
-
SOF
1 stop19h 00m
Multiple Airlines
Thu 8/65:45 am
SOF
-
BOS
1 stop23h 00m
Multiple Airlines
Deal found 5/26$741
This Orbitz deal was found by Cheapflights users on 5/24. 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.
Tue 7/286:50 pm
BOS
-
SOF
2 stops32h 30m
Multiple Airlines
Wed 8/2611:05 am
SOF
-
BOS
1 stop15h 50m
Multiple Airlines
Deal found 5/24$742
This FlightHub deal was found by Cheapflights users on 5/25. 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 7/148:05 pm
BOS
-
SOF
1 stop20h 10m
Lufthansa
Tue 8/257:25 pm
SOF
-
BOS
1 stop29h 15m
Lufthansa
Deal found 5/25$745
This United Airlines deal was found by Cheapflights users on 5/25. 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.
Sun 11/226:00 am
BOS
-
SOF
2 stops29h 20m
United Airlines
Sun 12/67:55 am
SOF
-
BOS
2 stops22h 59m
United Airlines
Deal found 5/25$748
This Mytrip deal was found by Cheapflights users on 5/25. 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 9/18:50 pm
BOS
-
SOF
3 stops23h 10m
Multiple Airlines
Wed 9/94:00 pm
SOF
-
BOS
3 stops33h 50m
Multiple Airlines
Deal found 5/25$750
This United Airlines deal was found by Cheapflights users on 5/25. 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 8/2712:27 pm
BOS
-
SOF
2 stops27h 48m
United Airlines
Thu 9/106:10 am
SOF
-
BOS
2 stops22h 49m
United Airlines
Deal found 5/25$751
This SWISS deal was found by Cheapflights users on 5/25. 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 SWISS is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/205:20 pm
BOS
-
SOF
2 stops18h 20m
SWISS
Mon 9/73:40 pm
SOF
-
BOS
1 stop30h 30m
SWISS
Deal found 5/25$752
This United Airlines deal was found by Cheapflights users on 5/24. 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.
Sun 8/238:05 pm
BOS
-
SOF
1 stop20h 10m
United Airlines
Sun 9/68:00 am
SOF
-
BOS
2 stops22h 59m
United Airlines
Deal found 5/24$754
This Air Canada deal was found by Cheapflights users on 5/26. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/710:40 am
BOS
-
SOF
2 stops16h 40m
Multiple Airlines
Sun 10/256:00 am
SOF
-
BOS
2 stops22h 37m
Multiple Airlines
Deal found 5/26$755
This Booking.com deal was found by Cheapflights users on 5/25. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/288:05 pm
BOS
-
SOF
1 stop20h 10m
Lufthansa
Wed 8/266:10 am
SOF
-
BOS
2 stops24h 49m
Lufthansa
Deal found 5/25$756

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 May 28, 2026.

Most accurate provider

Ovago
3 stars

Most trusted provider

Ovago
3 stars

Round-trip from

$741
(Kiwi.com)

One-way from

$248
(Kiwi.com)

Popular in

May

Cheapest in

February

Average price

$1,002
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. 22% potential increase in price ($184 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 5% potential price decrease ($34 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in May 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 May 28, 2026.
Use the filters below to find and compare flights from Boston to Sofia that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Thu 8/20

5:20 pm-6:40 pm

2 stops18h 20m

Sofia

Mon 9/7

3:40 pm-3:10 pm

1 stop30h 30m

$752

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Fri 10/9

6:00 am-12:10 pm

2 stops23h 10m

Sofia

Sun 10/25

7:55 am-2:30 pm

1 stop12h 35m

$798

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Sun 8/9

7:30 pm-7:20 pm

1 stop16h 50m

Sofia

Sun 8/23

9:05 pm-6:45 pm

2 stops28h 40m

$809
Quickest round-trip

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Mon 8/24

8:05 pm-11:15 pm

1 stop20h 10m

Sofia

Sun 9/20

12:55 pm-5:40 pm

1 stop11h 45m

$821

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Sat 7/4

5:45 pm-11:15 pm

2 stops22h 30m

Sofia

Fri 8/28

6:10 am-11:59 pm

2 stops24h 49m

$832

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Sun 10/11

8:05 pm-11:15 pm

1 stop20h 10m

Sofia

Thu 10/15

12:55 pm-5:40 pm

1 stop11h 45m

$843

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Fri 7/10

8:05 pm-11:15 pm

1 stop20h 10m

Sofia

Sat 8/29

8:00 am-11:59 pm

2 stops22h 59m

$844

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Tue 8/18

8:50 pm-3:30 pm

3 stops35h 40m

Sofia

Fri 9/4

12:40 pm-2:45 pm

2 stops33h 05m

$866

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Sun 7/26

8:00 am-11:15 pm

2 stops32h 15m

Sofia

Tue 8/4

6:10 am-5:40 pm

1 stop18h 30m

$880

BostonSofia

BOS - SOF

BOSSOF

Boston Logan Intl

Thu 8/20

7:23 pm-6:40 pm

2 stops16h 17m

Sofia

Sun 9/6

8:00 am-5:05 pm

2 stops16h 05m

$883

Flights are sorted by cheapest round-trip flights first.

Deals found on 5/25

Showing 1-10 of 20 resultsSorted by cheapest first
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 May.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
OvagoPrice Accuracy3 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
AranGrantPrice Accuracy3 starsTrust Score*3 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 Ovago to be most consistent on Cheapflights vs. Ovago Users can find the same prices on Boston-Sofia flight deals on Cheapflights vs. Ovago >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 Ovago the most. Ovago 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?

The best time to book flights from Boston to Sofia is 59 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 $460). Flying from Boston to Sofia in May is currently the most expensive (average of $1,002). 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.

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 May 28, 2026.
Peruse reviews from past customers who have flown with KLM,Air France, andTurkish 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
7.8
Good
1,526 reviews

Entertainment

7.2

Comfort

7.7

Crew

8.4

Overall

7.8

Boarding

7.8

Food

7.3

Reviews

1 / 20
6.0
Good

Anonymous,Apr 2026

OKC - ATL

Flight was ok - difficult as I had seat next to bathroom.. Food awful
KLM
7.8
Good
1,526 reviews
KLM
7.8
Good
1,526 reviews

Entertainment

7.2

Comfort

7.7

Crew

8.4

Overall

7.8

Boarding

7.8

Food

7.3

Reviews

1 / 20
6.0
Good

Anonymous,Apr 2026

OKC - ATL

Flight was ok - difficult as I had seat next to bathroom.. Food awful
Air France
7.4
Good
1,595 reviews
KLM
7.8
Good
1,526 reviews

Entertainment

7.2

Comfort

7.7

Crew

8.4

Overall

7.8

Boarding

7.8

Food

7.3

Reviews

1 / 20
6.0
Good

Anonymous,Apr 2026

OKC - ATL

Flight was ok - difficult as I had seat next to bathroom.. Food awful
Turkish Airlines
7.4
Good
4,399 reviews
KLM
7.8
Good
1,526 reviews

Entertainment

7.2

Comfort

7.7

Crew

8.4

Overall

7.8

Boarding

7.8

Food

7.3

Reviews

1 / 20
6.0
Good

Anonymous,Apr 2026

OKC - ATL

Flight was ok - difficult as I had seat next to bathroom.. Food awful
United Airlines
7.4
Good
9,763 reviews
KLM
7.8
Good
1,526 reviews

Entertainment

7.2

Comfort

7.7

Crew

8.4

Overall

7.8

Boarding

7.8

Food

7.3

Reviews

1 / 20
6.0
Good

Anonymous,Apr 2026

OKC - ATL

Flight was ok - difficult as I had seat next to bathroom.. Food awful
Lufthansa
6.8
Okay
8,032 reviews
KLM
7.8
Good
1,526 reviews

Entertainment

7.2

Comfort

7.7

Crew

8.4

Overall

7.8

Boarding

7.8

Food

7.3

Reviews

1 / 20
6.0
Good

Anonymous,Apr 2026

OKC - ATL

Flight was ok - difficult as I had seat next to bathroom.. Food awful

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 and United Airlines can get you from Boston to Sofia in just under 18h 20m. Your travel time can differ by up to 4h 50m. 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?

    United Airlines, at $394, was found to be the cheapest airline from Boston to Sofia.Alternate airlines to your destination round-trip include Austrian Airlines and Air France. United Airlines is 37% 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 $211 on Austrian Airlines. Other airlines that offer cheap prices include KLM from $218 and Lufthansa from $335 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 $460). Flying from Boston to Sofia in May is currently the most expensive (average of $1,002). 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

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Complete your trip

Complete your trip to Sofia by adding a car rental and/or hotel reservation to your travel itinerary.
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Plovdiv Airport car rentals

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 May 28, 2026.
AirlineCheapestAverageFlexibilityOn-time
Austrian AirlinesCheapest$394Average$622FlexibilityNo cancel feeOn-time78%
United AirlinesCheapest$394Average$688FlexibilityNo cancel feeOn-time69%
Air FranceCheapest$396Average$495FlexibilityNo cancel feeOn-time77%
KLMCheapest$403Average$527FlexibilityNo cancel feeOn-time75%
LufthansaCheapest$407Average$647FlexibilityNo cancel feeOn-time76%
SWISSCheapest$410Average$495FlexibilityNo cancel feeOn-time79%
British AirwaysCheapest$430Average$536FlexibilityNo cancel feeOn-time70%
ITA AirwaysCheapest$505Average$903FlexibilityNo cancel feeOn-time81%
Turkish AirlinesCheapest$524Average$734FlexibilityNo cancel feeOn-time77%

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