BOS - SOF

$300 Find Cheap Flights from Boston to Sofia

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Boston to Sofia departing on 5/18. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Sofia

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Boston to Sofia.
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Boston to Sofia.
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Everything you should know

Cheapest round-trip
$586
Typical prices: $617-$467
Multiple Airlines
Thu 9/24Thu 10/8
BOS - SOF • 2 stops
Cheapest one-way
$300
Typical prices: $604-$655
Multiple Airlines
Mon 5/18
BOS - SOF • 3 stops
Top airlines
Cheapest • from $609 (round-trip)
Best reviews • 7.8 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
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Nonstop flights
Not available
There are currently no direct flights between Boston and Sofia. You'll need at least 1 connection.
Insights
Insights
Insights
Insights
Top layover airports
Cheapest • Avg $550 (round-trip)
Shortest trip • 11h 00m (one-way)
Insights
Insights
Insights
Insights
When to book
in advance
Our data shows that travelers who book at least 2 weeks in advance save around 5% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
Cheapest • 27% price drop
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
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Flight Deals
Booking Insights
Flight Deals

Cheap Flights from Boston to Sofia (BOS-SOF)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Boston to Sofia that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Boston to Sofia

Thu, Sep 24 - Thu, Oct 8
Multiple Airlines Logo
11:00 pm - 1:15 am
BOS
-
SOF
19h 15m
2 stops
Multiple Airlines Logo
10:10 am - 9:15 pm
SOF
-
BOS
18h 05m
1 stop
$586Multiple Airlines
Wed, Sep 23 - Wed, Oct 7
Multiple Airlines Logo
11:00 pm - 12:15 pm
BOS
-
SOF
30h 15m
1 stop
Multiple Airlines Logo
9:40 pm - 9:15 pm
SOF
-
BOS
30h 35m
1 stop
$588Multiple Airlines
Wed, Sep 23 - Wed, Oct 7
Multiple Airlines Logo
11:00 pm - 12:15 pm
BOS
-
SOF
30h 15m
1 stop
Multiple Airlines Logo
5:45 am - 9:15 pm
SOF
-
BOS
22h 30m
2 stops
$603Multiple Airlines
Wed, Sep 9 - Wed, Sep 23
Multiple Airlines Logo
11:00 pm - 12:15 pm
BOS
-
SOF
30h 15m
1 stop
Multiple Airlines Logo
9:40 pm - 9:15 pm
SOF
-
BOS
30h 35m
1 stop
$607Multiple Airlines
Sun, Sep 20 - Wed, Oct 7
Multiple Airlines Logo
11:50 pm - 1:35 am
BOS
-
SOF
18h 45m
1 stop
Multiple Airlines Logo
6:00 am - 9:15 pm
SOF
-
BOS
22h 15m
2 stops
$608Multiple Airlines
Tue, Aug 25 - Tue, Sep 8
Austrian Airlines Logo
5:10 pm - 11:40 am
BOS
-
SOF
11h 30m
1 stop
Austrian Airlines Logo
6:55 pm - 1:50 pm
SOF
-
BOS
25h 55m
1 stop
$609Austrian Airlines
Wed, Aug 26 - Wed, Sep 9
Multiple Airlines Logo
5:20 pm - 10:20 am
BOS
-
SOF
10h 00m
1 stop
Multiple Airlines Logo
8:00 am - 1:50 pm
SOF
-
BOS
12h 50m
1 stop
$611Multiple Airlines
Mon, Oct 26 - Mon, Nov 9
Multiple Airlines Logo
9:40 pm - 6:20 pm
BOS
-
SOF
14h 40m
1 stop
Multiple Airlines Logo
12:35 pm - 1:30 pm
SOF
-
BOS
31h 55m
1 stop
$612Multiple Airlines
Mon, Aug 24 - Mon, Sep 7
Multiple Airlines Logo
5:20 pm - 12:15 pm
BOS
-
SOF
11h 55m
1 stop
Multiple Airlines Logo
12:25 pm - 1:50 pm
SOF
-
BOS
32h 25m
1 stop
$613Multiple Airlines
Thu, Oct 22 - Thu, Nov 5
Turkish Airlines Logo
9:50 pm - 8:45 am
BOS
-
SOF
27h 55m
1 stop
Turkish Airlines Logo
10:05 am - 7:05 pm
SOF
-
BOS
16h 00m
1 stop
$624Turkish Airlines
Booking Insights

KAYAK's insights & trends for Boston to Sofia flights

Get data-powered insights and trends into flights from Boston to Sofia to help you find the cheapest flights, the best time to fly and much more.

How much is a round-trip flight from Boston to Sofia?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from Boston to Sofia departing in September.

What is the cheapest month to fly from Boston to Sofia?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Boston to Sofia, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Boston to Sofia is February, where tickets cost $460 (return) on average. On the other hand, the most expensive months are May and June, where the average cost of round-trip tickets is $924 and $810 respectively.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Boston to Sofia, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from Boston to Sofia, you should book around 2 weeks before departure, which saves you about 5% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 26 weeks before departure.

Good to know

Low seasonNovember
Cheapest flight$300
Best time to beat the crowds with an average 25% drop in price.
Most popular time to fly with an average 10% increase in price.
Flight from Boston to Sofia

When to book flights from Boston to Sofia

Are your dates flexible? Find out the best times to travel from Boston to Sofia based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from Boston to Sofia

  • What are the layover options on the flight route from Boston to Sofia?

    Your layover will automatically depend on the airline you’re traveling with because each airline on this route has its preferred airport for layovers. For example, Turkish Airlines has all its layovers on this route scheduled for Istanbul. Similarly, Lufthansa has its layovers scheduled for Frankfurt or Munich while SWISS Airlines is scheduled for Zurich.

  • Do I need a visa to fly to Sofia?

    As it stands, U.S. citizens traveling to Bulgaria are not required to carry visas on entry as long as they are traveling on a regular passport and don’t plan on staying for longer than 90 days. In fact, the only mandatory requirement is your passport, with a validity of at least three months beyond the departure date from Bulgaria and one blank page for entry stamps.

  • Is public transport available from Sofia International Airport (SOF)?

    Access to the city center from Sofia Airport is possible through a range of options including bus, metro, and taxi. Taking a taxi is the most convenient although the bus and metro offer an affordable option. The metro in particular is a faster option and typically operates round the clock at intervals of fifteen minutes. To catch the metro, head over to the Airport Metro Station located in Terminal 2 and take the Metro line M2, which leads directly to the city center station Serdika.

  • Which is the most sustainable airline flying this route?

    In these modern times, it is pivotal that we think about the environment. While flying is by no means a sustainable way to travel, there are measures we can take to make our trips more sustainable, and it starts with using a sustainable airline. Lufthansa and American Airlines are a few of the airlines serving this route that have already adopted the use of Sustainable Aviation Fuel.

  • What is the cheapest flight from Boston to Sofia?

    In the last 3 days, the lowest price for a flight from Boston to Sofia was $300 for a one-way ticket and $586 for a round-trip.

  • Do I need a passport to fly between Boston and Sofia?

    Yes

  • Which airports will I be using when flying from Boston to Sofia?

    When flying out of Boston you will be using Boston Logan Intl. You will be landing at Sofia, also known as Sofia.

  • Which aircraft models fly most regularly from Boston to Sofia?

    We unfortunately don’t have that data for this specific route.

  • Which airline alliances offer flights from Boston to Sofia?

    oneworld, SkyTeam, and Star Alliance are the airline alliances operating flights between Boston and Sofia, with oneworld being the most commonly used for this route.

  • What is the most popular layover when flying to Sofia from Boston?

    Frankfurt am Main is the most popular layover city among KAYAK users traveling from Boston to Sofia.

  • Which is the best airline for flights from Boston to Sofia, KLM or Austrian Airlines?

    The two airlines most popular with KAYAK users for flights from Boston to Sofia are KLM and Austrian Airlines. With an average price for the route of $499 and an overall rating of 7.8, KLM is the most popular choice. Austrian Airlines is also a great choice for the route, with an average price of $627 and an overall rating of 7.6.

  • How does KAYAK find such low prices on flights from Boston to Sofia?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Boston to Sofia.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Boston to Sofia?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Sofia from Boston is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Boston to Sofia?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Sofia with an airline and back to Boston with another airline. Booking your flights between Boston and SOF can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Boston to Sofia?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Sofia from Boston up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

KAYAK’s top tips for finding a cheap flight from Boston to Sofia

  • Business travelers looking to work while flying should book their flights with Lufthansa. It provides Wi-Fi to all passengers, allowing you to browse the internet, send emails, and check your social media while flying.
  • To get access to an airport lounge during your layover, consider booking your flight with an airline that has a lounge at the airport. For example, when you book with Lufthansa, you can access the Lufthansa Senator Lounge during your layover at Frankfurt Airport.
  • When you book an economy-class ticket with United Airlines, you can be upgraded to the next class at a lower cost compared to what you would’ve paid if you booked a first-class ticket from the get-go.
  • If you have booked your flight with Turkish Airlines, consider upgrading with the EcoFly promotion and get two checked bags plus a carry-on inclusive of your ticket instead of just one carry-on bag.
  • A quick way into Boston Logan International Airport (BOS) from downtown Boston is via taxi. They are available at every corner of the city and will take you directly to the airport terminal. When rush hour traffic is a problem, the Blue Line from South Station offers a great alternative.

Reviews of the top 5 airlines serving from Boston to Sofia

 
See real verified KAYAK customer reviews for airlines flying from Boston to Sofia. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Boston to Sofia? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.8
KLMOverall score based on 1510 reviews
7.7Comfort
7.1Entertainment
8.4Crew
7.8Boarding
7.3Food
Airline reviews

As per usual when you Hit the UK it's a slow process through customs Not as efficient at Thailand for sure

10.0 ExcellentDiane, Apr 2026
AMS - HUY
Read more KLM reviews

As per usual when you Hit the UK it's a slow process through customs Not as efficient at Thailand for sure

The crew were unprofessional with a racist element. I was physically abused as well from one of the crew members

Crew is not the cheerful type. very slow meal service (this is their style as have flown this many times)

Flight was on time, staff are friendly and helpful onboard.

They forgot to serve food and the crew was very unfriendly. Never experienced such a bad KLM flight. Usually fly from Toronto. New York was different.

The immigration hall in Amsterdam was understaffed, so passport checking was slower than it should be for a major airport. They need to get the automatic readers up and running for non EU passport holders. Waiting in line after a long flight feels a bit abusive.

Over 1 Hr delay. No APU so no AC on ground. Plane was hot during boarding and then they closed the doors over 20 minutes before engine start so interior of plane was steamy hot and stuffy. Could have been helped by opening doors until ready to depart.

KLM remains a quality flag carrier airline which maintains its standards whilst all their competitors are lowering theirs.

Our first flight was delayed so we missed our connecting flight. However it was easy to book a later flight on their app.

My flight was delayed by 6 hours then I missed BOTH of my connecting flights, I then had to stay in the AIRPORT at JFK because soooooo many people also suffered from missing flights and there was no hotels available. I would like to be compensated for this experience! I had to stay in the airport for over 16 hours!

Middle seats SUCK!!!! I paid more money than I should have because of your terrible site Kayak.com. I'll try to use your competitors going forward. I am so disappointed you would play off business class.com as business class seats

The boarding was efficient. The entertainment system was a bit unstable but Air France has a good selection of movies.

They lost my bag and I still haven’t received it yet

Communication on the delay, rebooking and how to get a hotel was poor. Mails, airport check-in and transfer desk said different things.

Safe and stable made me sleepy and I slept and dreamt 😂😂😂😂

Food was really mediocre for premium economy in comparison to other airlines… the crew was nowhere to be found… 14 hour flight…

I don’t like that an equipment change caused my seat to change from 23A to 44A. The boarding was also delayed. The crew were excellent, however and very attentive. The food was not bad.

Worst airlines either. First leg was delayed because of crew not available. My connection was missed so they booked me automatically the next day! But, impossible to get anyone on site, web site does not let me access my reservation anymore, confirmed by useless agents over the phone. My 2-leg trip with part in business class arriving at 4:10pm ends up in an awful 3-leg arriving at 9pm the next day with no way to even choose the seats and of course at the very end of the plane. I can understand problems arrive but the way Air France handle it is just unacceptable. You are on your own. Apparently getting you to your destination is the only thing they consider their duty. The customer experience and fatigue is none of their concern. And I have a status with them. I will reconsider my priorities when flying with Air France and encourage everyone to do the same.

Our flight crew were terrific. And they handle a difficult passenger with finesse.

Excellent, Lima to Paris. But Paris to Amsterdam, delayed, missed my flight and KLM treated its missed flights passengers very badly, terribly bad. No hotel accommodation given. Passengers were told to find their own hotel accommodation and claim at reasonable rate and left the booth and literally with armed Police Officers listening to passengers complains. For three hours, after moving by Uber from hotel to hotel and calling and booking online, no hotel was available. I had to return to the airport and seat/sleep on the benches, suffering the cold, and rats running around until my new allocated flight the next day. It was the most terrible KLM treatment even seen and being a Business Class passenger. Still mentally suffering to date as a result.

Very comfortable in business class. Excellent service. Good food. Smooth trip.

The seats seems abit small and the reclining is too much, the seat in front of me came back too much and made it uncomfortable for me.

As a first time flyer with Turkish Airlines. My experience was very good due to the factor that there were to many passengers on the my first flight compared to my connecting flight. However, I know that nothing is perfect and all companies are trying to accommodate their passengers to the best way possible. I will always say, a FEW INCHES will go LONG WAY. That's something all airliners should consider, and not only the money aspect!!! A long time commitment is better than one time service! Thank you

Flight was delayed. While standing at the gate, a note appeared on the sign saying the gate had changed to a gate far away. No member of the Turkish airlines team got on the microphone to instruct passengers to go to the other gate, to ignore the chiron, etc. Finally, the message disappeared. Eventually, the flight began to board. Very slowly. More slowly than I experience with other airlines. Though Istanbul may just be slow . . . In all other ways, great flight, great entertainment (top notch movies), great service, excellent food, comfortable lie-flat seat, dimmed lights, etc.

Staff at the airport wasn't helpful or friendly. Probably the worst airport experience I have ever had, going and coming. The staff on the plane was better. Still not super friendly or personable. However, they were not rude like airport staff. They ran out of certain menu items. Maybe could have been prepared better? Overall just ok.

It was a pleasant experience. In flight entertainment could have been better

The desk crew at the LAX crew could do better. A girl named Mahesi was very abrasive and unfriendly. She needs a better customer service uproar.

It was peaceful excited We enjoyed it always Turkish peaceful excited

Istanbul to Lahore flight was less than standard for international business class cabins. Seat did not were not flat and it did not operate easily. I had to push buttons hard repeatedly to operate the seat. I was in 5A seat

IAH to Istanbul was outstanding across the board. The flight from Istanbul to Male was good, not great.

Some crew were unfriendly or in some cases just straight up rude.

Booked through Kayak Business, had a seat in middle and towards back due to booking rate, not comfortable.

Was great in general, try to respect time and excuses when slight changes have been made, appreciated!

A long delay. Don't travel late in the day.

Super friendly with lots of drink options an entertainment. Friendly crew.

Standard flight with a drinks and a snack- overall very quick flight. The flight attendants were very strict, bordered on rude.

Outstanding service, efficient & friendly crew, flight was safe, comfortable & on time

United Airline crews were very friendly and very attentive. 12 hours flight was gone like in a shorter one.

Delayed - weather wasn't bad at either end. Also sat on tarmac in ORD.

Food was surprisingly delicious. Space in the seat is horrible when the seating front is reclined. Movie offerings were terrible. Crew was friendly and helpful.

Flight was delayed by several hours and then cancelled due to weather. But Staff was very helpful getting me on a different flight. United should offer food coupons and tooth brush and paste for stranded passengers

I upgraded to the business class cabin. It was the poorest business class I have ever experienced. No access to any business lounge in Tampa airport. Seats are not comfortable. I had a window seat and had to step/crawl over the next seat. Food was mediocre and service below average for business class. Bathroom location was ridiculous. No place to wait. I cannot believe I paid this kind of money and will never fly Lufthansa Discover again. They really should reimburse me somehow.

Boarding was disorganized. The door to one to the toilets wouldn’t lock. The plane was shockingly cramped, and clearly used for domestic flights due to the menus for items to sell domestic travelers. United should be ashamed of its small seats, tiny unclean toilets, and money grubbing stance toward services, compared to Lufthansa, Emirates, and most international carriers United is awful.

Was never allowed on and not refunded the full amount of the ticket plus charged a $300 processing fee.

Terrible. Lost our luggage for 4 days. Did not advise passengers there was a strike in Barcelona Airport and had zero personnel on hand at airport to advise passengers on where to go to file claims. We had to fend for ourselves. No assistance at all other than an online claims submission process that we had to find out about on our own.

Lufthansa cancelled our flight from Los Angeles to Naples Italy on March 10 for scheduled flight on March 12 Very stressful experience trying to arrange alternatives. Will never fly again with Lufthansa

Everything could have been better. What needed to be wrong with United went wrong

The staff was bit rude when I asked for an extra drink after one beer, asked for one wine glass.

Very good, i got two seats for myself, and was comfortable with the blanket i got

I hated the FRA Airport. Confusing signage, including the path to Immigration and Security It seems that the airport grew haphazardly over the years. I have been through multiple WW Hubs with much better experiences.

Everything you need to know for your flight from Boston to Sofia

Information on your arrival and departure airports