BOS - SOF

$348 Find Cheap Flights from Boston to Sofia - Compare and Save

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 7/26. 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
$798
Typical prices: $747-$438
TAP AIR PORTUGAL
Tue 9/8Tue 9/29
BOS - SOF • 2 stops
Cheapest one-way
$348
Typical prices: $446-$688
Multiple Airlines
Sun 7/26
BOS - SOF • 3 stops
Top airlines
Cheapest • from $798 (round-trip)
Best reviews • 7.8 score
Airline reviews
Airline reviews
+1
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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 $547 (round-trip)
Shortest trip • 10h 57m (one-way)
Insights
Insights
Insights
Insights
When to book
in advance
Our data shows that travelers who book at least 3 weeks in advance save around 12% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
Cheapest • 28% 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

Tue, Sep 8 - Tue, Sep 29
TAP AIR PORTUGAL Logo
6:05 pm - 10:50 pm
BOS
-
SOF
21h 45m
2 stops
TAP AIR PORTUGAL Logo
6:40 pm - 2:45 pm
SOF
-
BOS
27h 05m
2 stops
$798TAP AIR PORTUGAL
Tue, Nov 10 - Tue, Nov 24
Austrian Airlines Logo
1:30 pm - 6:00 pm
BOS
-
SOF
21h 30m
2 stops
Austrian Airlines Logo
7:55 am - 1:30 pm
SOF
-
BOS
12h 35m
1 stop
$799Austrian Airlines
Wed, Aug 26 - Sun, Dec 20
Multiple Airlines Logo
8:50 pm - 12:10 am
BOS
-
SOF
20h 20m
3 stops
Multiple Airlines Logo
10:25 am - 2:40 pm
SOF
-
BOS
35h 15m
2 stops
$801Multiple Airlines
Thu, Sep 10 - Thu, Sep 24
Multiple Airlines Logo
8:50 pm - 2:55 am
BOS
-
SOF
23h 05m
2 stops
Multiple Airlines Logo
7:30 pm - 2:45 pm
SOF
-
BOS
26h 15m
2 stops
$802Multiple Airlines
Mon, Nov 9 - Fri, Nov 20
Multiple Airlines Logo
5:50 pm - 1:35 pm
BOS
-
SOF
12h 45m
1 stop
Multiple Airlines Logo
8:20 pm - 2:40 pm
SOF
-
BOS
25h 20m
2 stops
$803Multiple Airlines
Fri, Sep 11 - Sun, Sep 27
Turkish Airlines Logo
9:50 pm - 3:00 pm
BOS
-
SOF
34h 10m
1 stop
Turkish Airlines Logo
3:50 pm - 7:55 pm
SOF
-
BOS
35h 05m
1 stop
$804Turkish Airlines
Mon, Oct 12 - Mon, Oct 26
Multiple Airlines Logo
8:50 pm - 11:40 pm
BOS
-
SOF
19h 50m
2 stops
Multiple Airlines Logo
4:50 pm - 9:45 pm
SOF
-
BOS
34h 55m
3 stops
$805Multiple Airlines
Mon, Sep 7 - Sat, Sep 26
Turkish Airlines Logo
9:50 pm - 3:00 pm
BOS
-
SOF
34h 10m
1 stop
Turkish Airlines Logo
9:35 am - 7:55 pm
SOF
-
BOS
17h 20m
1 stop
$808Turkish Airlines
Sat, Nov 7 - Mon, Nov 16
Turkish Airlines Logo
9:00 pm - 8:55 pm
BOS
-
SOF
16h 55m
1 stop
Turkish Airlines Logo
9:40 am - 6:05 pm
SOF
-
BOS
15h 25m
1 stop
$809Turkish Airlines
Mon, Nov 9 - Mon, Nov 23
Multiple Airlines Logo
5:50 pm - 1:35 pm
BOS
-
SOF
12h 45m
1 stop
Multiple Airlines Logo
9:35 pm - 2:40 pm
SOF
-
BOS
24h 05m
2 stops
$810Multiple 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 $1,008 and $938 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 3 weeks before departure, which saves you about 12% 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$348
Best time to beat the crowds with an average 25% drop in price.
Most popular time to fly with an average 12% 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 5 days, the lowest price for a flight from Boston to Sofia was $348 for a one-way ticket and $798 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 $545 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 $639 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 1528 reviews
7.2Entertainment
7.3Food
8.4Crew
7.8Boarding
7.7Comfort
Airline reviews

As always, it’s a pleasure to travel with KLM. It is one of my favorite airlines.

10.0 ExcellentGeorge, May 2026
OTP - AMS
Read more KLM reviews

As always, it’s a pleasure to travel with KLM. It is one of my favorite airlines.

There were no charge points for phones on the economy seats. The seats were comfortable overall. Food was okay.. flight was on time

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)

Empty seats next to me - wish it had been for a longer flight!!

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.

The crew was attentive. The food was delicious. The flight was smooth.

The preboarding and the gate organizing management was poor, unorganized and mismanaged. While standing in the business line I kept getting ignored and the personnel kept checking in others, right in front of me until I finally spoke up and pointed out their clear signs of ignoring me while patiently waiting to be checked in. Once checked in the gate the personnel kept chit-chatting and not managing which group is to board, being totally nonchalant, unorganized and behaving amateur-like . Very unprofessional and unlike the quality the Austrian Airlines brand otherwise provides. The crew on the plane are always fantastic and the best. What a shame the crew on the ground was so mediocre.

Absolutely the worst food I've ever had on any flight. Otherwise, the flight is OK - just your regular transatlantic economy. Condor should stop saving pennies on meals. They save a penny, lose a dollar.

The layover period at Frankfurt of one hour and forty minutes was not enough time to clear the two-hour line at passport control: we missed the flight to San Francisco. Condor did a good job rebooking us that same day, but our bags ended up in Los Angeles.

This is truly the worst travel experience of my life. The UK ETA program had a technical failure, and I was stuck in limbo for 24 hours, unable to board my flight and unable to navigate anything in my itinerary. I had to rebook an entirely new flight and I’m now out doubled the money. Unconscionable.

OK, would prefer some meat for dinner, not just pasta although was tasty. There was only one dish, no choices

Flight delayed with no explanation. Boarding was confused (proceed to plane, go back to waiting area).

It was a great experience. The aircraft is a bit dated but other than that it was great.

Last few years I didn't not have great experience with United Airlines.

Booked economy. Seat felt like it was a bit more roomy than my last trans Atlantic flights. I had a nice person sitting next to me. Everything was as good as it could be considering you are 35,000 feet up in the air and in a metal container. Beers, wine, food were all readily available. Plenty of movies and shows to watch. Friendly flight staff

Entertainment system is okay, flight attendants were ok. Leg space very narrow, I couldn’t get what I wanted to eat, dinner nor breakfast.

Excellent experience with business class area. Staff was attentive and food was amazing. Only one bathroom for business class which was logistically difficult for the staff while preparing meals. Need to offer fluids with meals. I did not get enough water to drink. But overall I rate it 5 star.

On time, great food, good drink selection! Only down was alcohol-free lounge. Lufthansa had a much better offering!

Be honest of what you sell: This was sold as Business Class on all three legs, while the JetBlue plane didn't even have business class seats, and wanted $164 for extra legroom seats.

Seat assignments for family traveling with 2 children. Loud crowd during sleep time

It was crowded… the bathrooms dirty and smelly. The seats have been made even smaller.

delayed to take off from detroit by 3 hours lost baggage in istanbul and now in venice without baggage

Seats were very tight with poor legroom - and I am average height. During the 12 hour flight, tiny paper cups of drinks we're only offered during the super and breakfast services, with the crew nowhere to be seen in between. One of the bathrooms was out of order, leading to long lines waiting to use the remaining two available to the economy class passengers.

short flight but we still got a very nice lunch and the crew did an excellent job in taking care of us

For that price on Business class, I expected to have the pod seats. These were configured as 2/3/2 and my seat mate talked half the flight with a friend across the isle, loudly. Very uncouth.

The entertainment they offer could use some games, and maybe they could add some cookies to the snack menu. And the automated messages are a bit repetitive. But it was comfortable temperature wise and the seats were comfortable. The crew is very polite and helpful

The entertainment is a bit limited, it would be better if they added some games to play besides the movies and tv shows. But the seats are comfortable and the crew is polite

This planes staff was top tier. Everything went great and had a great flight home.

Food was great. Staff was phenomenal. Seats were a bit hard and could use a lot more entertainment options as far as movies to choose from. WiFi was good. Overall great trip.

This was an overnight flight, and in the morning they did know coffee service. How you can throw passengers in a San Francisco airport at 5:40 a.m. in the morning and not giving them Coffee is a crime.

I was promised by United Airline (operated by ANA) that I will be seated together with my kids as I am the only adult flying with two minors. We did not get seats together in our 11 hours flight from LA to Tokyo. When asked at the gate, ANA representative said United Airline should have informed them that there is a parent flying with two minors. He said they can’t do anything in the system as the flight is full. He ask me to ask passengers next to me and the kids if they are willing to change seats. This is ridiculous! However, I went in the flight and asked other passages but no one willing to change seats. 11 hours and we were seating separately. I was very disappointed with this. It made things super inconvenient for me.

Our flight was delayed several Times due to mechanical issues. Although I understand this may happen at times, it was very inconvenient and we had to book a hotel for an overnight stay. We were traveling with my 3-yo grandson and waiting at the airport from noon until 6:30pm with no reassurance that our next rescheduled flight would depart, we had to decide what’s best for him. A day later, I found out that I may be able to demand compensation if my flight is delayed more than 4 hours. I will hav to read the fine print next time.

Flight cancelled instead of leaving Friday am now, maybe, leaving Sunday

The pilot had to extend the flight time from san antonio to Houston to burn off fuel. This caused a lot of unnecessary stress since we had a tight connection to Aruba. And with no other flights going to Aruba we were worried about spending a night in Houston. We had to to run to our connection because of the flight crews mistake. Not happy.

Service was professional and quick. Premium economy seat was comfortable given the class

We sat in our seats on the tarmac for almost 3 hours due to storms. They would not give us water or a snack. We were to depart at 7.30 pm and it was about 10.30 when we took off. No dinner until much after that. Beef type noodle dish was terrible with about a teaspoon of beef in it. The breakfast sweet waffle with egg and sausage inside was horrible. An English muffin sandwich would have been much better. Food was the worst in all of our years of traveling the world.

Our screen kept turning off ...3 times...had to get crew attention to turn it on again

They messed up my seat so I didn’t get the one I paid for

Put me on standby; flight was late; missed my connecting flight; disaster

Flight attendants were fine, seats a bit hard but I use a cushion for extra support. The only issue was it was a bit too cool and I needed to ask for and received and extra blanket. I survived!!!

Very few things and/or people are excellent. It was very good.

Extremely uncomfortable seats. Experience was like a Frontier Airlines flight. Would not fly it again.

Very, very tight legroom. They must’ve jammed in an additional few rows of seat seating. Denver to Munich was the least legroom I’ve ever had on any flight, let alone a multi hour international journey. I will not take that flight again.

In my first flight with Air Canada we sat in the plane for 4:00pm to 6:30pm. Finally we were asked to get off the plane and we were told the flight was cancelled after 7:00pm There was o clear explanation of what was the problem. I was booked without my permission on a Delta Flight at 7:30pm that was leaving at 8:00pm and I still had to go get my luggage(my final destination was Rome with one stop in Toronto. The luggage claim for Canada was closed so had to return to finally get it on the luggage belt.. Of course I missed the Delta flight and all the next day flights were booked. I also lost what I paid for my stay in Rome because I did nt cancel in time. A complete nightmare.

Good food, overall very comfy. The flight was full so obviously not optimal, but it is what it is.

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

Information on your arrival and departure airports