BOS - SOF

$241 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 4/26. 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
$501
Overall average: $608
Lufthansa
Mon 4/13Mon 4/27
BOS - SOF • 1 stop
Cheapest one-way
$241
Typical prices: $656-$725
Multiple Airlines
Sun 4/26
BOS - SOF • 3 stops
Top airlines
Cheapest • from $501 (round-trip)
Best reviews • 7.8 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
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 $564 (round-trip)
Shortest trip • 10h 56m (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 10% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
Cheapest • 25% price drop
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
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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

Mon, Apr 13 - Mon, Apr 27
Lufthansa Logo
8:05 pm - 11:00 pm
BOS
-
SOF
19h 55m
1 stop
Lufthansa Logo
7:25 pm - 5:40 pm
SOF
-
BOS
29h 15m
1 stop
$501Lufthansa
Mon, Apr 6 - Mon, Apr 20
Multiple Airlines Logo
6:15 am - 6:40 pm
BOS
-
SOF
29h 25m
2 stops
Multiple Airlines Logo
7:00 pm - 3:40 pm
SOF
-
BOS
27h 40m
1 stop
$502Multiple Airlines
Mon, Apr 6 - Mon, Apr 20
SWISS Logo
5:20 pm - 12:15 pm
BOS
-
SOF
11h 55m
1 stop
SWISS Logo
3:40 pm - 3:10 pm
SOF
-
BOS
30h 30m
1 stop
$507SWISS
Mon, Apr 13 - Mon, Apr 27
Multiple Airlines Logo
9:40 pm - 10:20 am
BOS
-
SOF
29h 40m
1 stop
Multiple Airlines Logo
7:25 pm - 5:40 pm
SOF
-
BOS
29h 15m
1 stop
$510Multiple Airlines
Tue, Apr 14 - Tue, Apr 28
Lufthansa Logo
5:45 pm - 1:05 pm
BOS
-
SOF
12h 20m
1 stop
Lufthansa Logo
12:55 pm - 5:40 pm
SOF
-
BOS
11h 45m
1 stop
$511Lufthansa
Wed, May 6 - Wed, May 20
Turkish Airlines Logo
9:50 pm - 1:15 pm
BOS
-
SOF
32h 25m
1 stop
Turkish Airlines Logo
9:05 pm - 7:55 pm
SOF
-
BOS
29h 50m
1 stop
$512Turkish Airlines
Mon, Apr 13 - Mon, Apr 27
Multiple Airlines Logo
9:40 pm - 10:20 am
BOS
-
SOF
29h 40m
1 stop
Multiple Airlines Logo
7:25 pm - 5:40 pm
SOF
-
BOS
29h 15m
1 stop
$513Multiple Airlines
Tue, Apr 28 - Tue, May 5
Austrian Airlines Logo
5:10 pm - 3:20 pm
BOS
-
SOF
15h 10m
1 stop
Austrian Airlines Logo
6:55 pm - 1:50 pm
SOF
-
BOS
25h 55m
1 stop
$514Austrian Airlines
Tue, May 5 - Tue, May 19
Turkish Airlines Logo
9:50 pm - 8:15 pm
BOS
-
SOF
15h 25m
1 stop
Turkish Airlines Logo
3:50 pm - 7:55 pm
SOF
-
BOS
35h 05m
1 stop
$515Turkish Airlines
Mon, Apr 6 - Fri, Apr 17
Multiple Airlines Logo
6:15 am - 6:40 pm
BOS
-
SOF
29h 25m
2 stops
Multiple Airlines Logo
6:10 am - 5:40 pm
SOF
-
BOS
18h 30m
1 stop
$518Multiple 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.

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 $803 and $789 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 10% 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$241
Best time to beat the crowds with an average 23% drop in price.
Most popular time to fly with an average 13% 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 $241 for a one-way ticket and $501 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 $471 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 $623 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 1472 reviews
8.4Crew
7.6Comfort
7.8Boarding
7.1Entertainment
7.3Food
Airline reviews

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

2.0 MediocreNewton, Mar 2026
IAD - AMS
Read more KLM reviews

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!

I appreciate that KLM was proactive in informing me of the 2 hour delay which enabled me to replan my travel. It was a bit stressful not knowing whether my connection from Montreal to Ottawa was happening. But the ground and air crew did a good job at comforting and assuring me.

The flight itself was fine, but due to a snow delay my connection to Lisbon was delayed by six hours. Despite this, Swiss Air still managed to lose my luggage. Not acceptable. Someone else on the flight also lost their luggage.

Bad experience overall. Crew did not provide food for our 2 year old (even though we specifically bought a child infant seat for her and literally bought another full price flight), which was unacceptable. And we had to pay $310 each way to carry our ski equipment even though they advertise it as something that is free. Tickets were purchased the same way as usual, but they told us we had Economy Light tickets (I never elected to have such seats). Just plain manipulation and false advertisment. Very disappointed overall about this airline.

The trip was great until my luggage was lost on transfer from United to Swiss. It took Swiss 3 days to get my luggage to me though it was located almost immediately.

Really BAD check in experience. My bag was left in Geneva and I have not received it yet. I have been in Stockholm 5 days without clothes to change. The flight was good but very unhappy with the post service support.

Horrible!! The WiFi was not working, the food was awful

We’ve never been more uncomfortable on a flight than we have on this particular one. The seats in front of us reclined so far back that when the person reclined their seat of broccoli, it almost hit me in the face and left me with literally no room to move that said I had to recline my seed in which made the person behind me upset. It seemed like the seats also would recline without even pressing the button in the armrest and would unrecline as well for that same reason, and it also seemed that some seats reclined more than others. The bottom cushions of the seat were so thin that even after one hour of an 11 hour flight, our tailbones were so sore. It seemed like an overall old airplane. It also didn’t have individual air vents and it was extremely hot the entire flight. Several passengers were commenting on how hot it was. The breakfast was some kind of flavorless triangle, puffy egg, laying in a watery bed of steamed peppers and onions and spinach. It was not appetizing at all. The flight crew was extremely nice so that was a nice thing this flight attendant. They let us try different types of Swiss sodas, which was really nice and the dinner was actually delicious but still overall given the other considerations. It was pretty much a miserable flight without basic seat comfort.

They lived up to the Swiss reputation of excellent operation in all aspects. Zurich is a great place to make connections to other parts of Europe.

Food used to be better and comfort was not attainable after 5 hours everything starts hurting.

horrible.. they cause such a problem and my daughter 14 years old was stranded in san francisco

I can’t even the whole trip was a catastrophe

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.

Not consistent with the food quality (I mean taste not freshness)

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.

Both our flights were delayed. Almost didn’t get in the second flight. Staff was rude to the bone.

Both my flight where delayed Had 25min to make it to my transfer flight

Everything was on time and service on the flight was great!

Wifi Bluetooth features for watching in flight movie was horrible. Screen kept blacking out no connection of sound although it said connected. Other than that smooth trip .

The 777’s economy seat’s legroom was more tolerable than expected. I appreciate the reclining mechanism which slides the seat forward to minimize cannibalizing the space behind. The food was terrible: very salty.

The travel company that you have on your site did me so wrong. I don’t know how it happened, but they put my son‘s name on my plane ticket flying to Vietnam. Along with his birthday. They would not have let me fly from Fort Myers to Ho Chi Minh City. I don’t think that I can ever use your service again. I typed my information into the browser along with my passport number and four days before I’m leaving I have to quickly search another ticket to fly out here.

Seats are uncomfortable. This has been a trend in the industry for decades. Trying to fit more seats on each plane to increase profits at the expense of the passenger.

The flight was delayed so we were dead tired, and after that the turbulence was horrible. I was very scared.

It’s always a great time flying with united airlines.

Good flight. Efficient boarding and competent flight crew. No problems until we arrived at our destination gate. We were early so there was an aircraft at the gate that had to move before we could pull in. Then, due to the type of aircraft we flew, the cabin door could not be opened until some luggage from the cargo bay was offloaded to preserve center of gravity characteristics. So, that further delayed deplaning. Despite being 20 minutes early on landing, we ended up being 5 to 10 minutes late after all the delays.

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.

Economy Priority seats are extremely uncomfortable. There is no way to escape the boxed in feeling, particularely because the distance between to rows are too short, the hard edge of the front row is keeping legs confined. There is no elevated place to put your feet. I am of average, European size.

Terrible. Both flights were significantly delayed, no luggage, made me check my small bag when many, many others had much larger carry-ons, not even a bottle of water . . . I will not fly Discover Airlines again.

I was deceived on the Kayak site expecting a ticket, but instead finding a "standby" reservation. When I tried to change the ticket, I paid almost twice the price of the original ticket. Then, the airline refused to give me the reserved seat I had chosen and paid for. I think I deserve a refund for this leg of my trip because I was doubly charged and did not receive what I had paid for. I put in a complaint with Lufthansa because the ticket was sold originally sold as a flight they listed. Someone here needs to take responsibility.

Excellent service; they helped me reschedule so I can fly in an earlier flight

I had a good comfortable seat. There was nearly an hour delay. There was an accident with the champagne, but I was well compensated. These things happen sometimes.

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

Information on your arrival and departure airports