BOS - SOF

$239 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 2/9. 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
$346
Overall average: $489
Austrian Airlines
Tue 2/17Tue 3/3
BOS - SOF • 1 stop
Cheapest one-way
$239
Typical prices: $424-$555
Multiple Airlines
Mon 2/9
BOS - SOF • 2 stops
Top airlines
Austrian Airlines
Cheapest • from $346 (round-trip)
KLM
Best reviews • 7.7 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
When to travel
November
Cheapest • 28% price drop
July
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

Tue, Feb 17 - Tue, Mar 3
Austrian Airlines Logo
6:25 pm - 11:50 am
BOS
-
SOF
10h 25m
1 stop
Austrian Airlines Logo
7:55 am - 5:21 pm
SOF
-
BOS
16h 26m
2 stops
$346Austrian Airlines
Mon, Feb 16 - Mon, Mar 2
Multiple Airlines Logo
8:40 pm - 10:45 pm
BOS
-
SOF
19h 05m
1 stop
Multiple Airlines Logo
6:45 pm - 2:05 pm
SOF
-
BOS
26h 20m
1 stop
$352Multiple Airlines
Wed, Mar 4 - Tue, May 5
Lufthansa Logo
8:40 pm - 6:20 pm
BOS
-
SOF
14h 40m
1 stop
Lufthansa Logo
12:55 pm - 5:40 pm
SOF
-
BOS
11h 45m
1 stop
$355Lufthansa
Tue, Mar 17 - Tue, Mar 24
Austrian Airlines Logo
7:25 pm - 11:50 am
BOS
-
SOF
10h 25m
1 stop
Austrian Airlines Logo
7:55 am - 3:05 pm
SOF
-
BOS
13h 10m
1 stop
$356Austrian Airlines
Mon, Apr 20 - Wed, Apr 29
Multiple Airlines Logo
5:20 pm - 12:15 pm
BOS
-
SOF
11h 55m
1 stop
Multiple Airlines Logo
8:00 am - 1:50 pm
SOF
-
BOS
12h 50m
1 stop
$361Multiple Airlines
Sun, Mar 15 - Mon, Mar 30
Lufthansa Logo
9:40 pm - 6:20 pm
BOS
-
SOF
14h 40m
1 stop
Lufthansa Logo
7:25 pm - 5:40 pm
SOF
-
BOS
29h 15m
1 stop
$366Lufthansa
Wed, Mar 18 - Wed, Apr 1
Multiple Airlines Logo
6:40 pm - 1:15 pm
BOS
-
SOF
12h 35m
2 stops
Multiple Airlines Logo
8:00 am - 5:57 pm
SOF
-
BOS
16h 57m
2 stops
$368Multiple Airlines
Wed, Mar 18 - Wed, Apr 1
Multiple Airlines Logo
6:40 pm - 1:15 pm
BOS
-
SOF
12h 35m
2 stops
Multiple Airlines Logo
8:00 am - 1:50 pm
SOF
-
BOS
12h 50m
1 stop
$369Multiple Airlines
Sun, Apr 19 - Wed, Apr 29
Multiple Airlines Logo
8:05 pm - 11:10 pm
BOS
-
SOF
20h 05m
1 stop
Multiple Airlines Logo
6:10 am - 10:38 pm
SOF
-
BOS
23h 28m
2 stops
$375Multiple Airlines
Tue, Mar 17 - Tue, Mar 31
Multiple Airlines Logo
7:25 pm - 11:50 am
BOS
-
SOF
10h 25m
1 stop
Multiple Airlines Logo
12:55 pm - 9:27 pm
SOF
-
BOS
15h 32m
2 stops
$376Multiple 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 November, where tickets cost $478 (return) on average. On the other hand, the most expensive months are June and May, where the average cost of round-trip tickets is $896 and $824 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 1 week before departure. For the absolute cheapest price, our data suggests you should book 9 weeks before departure.

Good to know

Low seasonNovember
Cheapest flight$239
Best time to beat the crowds with an average 28% drop in price.
Most popular time to fly with an average 11% 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 $239 for a one-way ticket and $346 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 SWISS?

    The two airlines most popular with KAYAK users for flights from Boston to Sofia are KLM and SWISS. With an average price for the route of $547 and an overall rating of 7.7, KLM is the most popular choice. SWISS is also a great choice for the route, with an average price of $684 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.
7.7
KLMOverall score based on 1443 reviews
8.4Crew
7.1Entertainment
7.6Comfort
7.8Boarding
7.3Food
Airline reviews

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

8.0 ExcellentShereen, Dec 2025
AMS - YUL
Read more KLM reviews

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 baggage drop-off in Stuttgart is bad: after online check-in you cannot use the automated baggage drop off as indicated on the website. You can use the terminals but have to cue to 1 of three open and slowly working counters to drop the bags. took about 45 minutes wait time.

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.

Cabin crew were excellent, very proffesional, polite and friendly, in flight snack was underwhelming, a packet of cheese biscuits, im sure KLM could run to a sandwich!

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.

My experience was wonderful. The professionalism of the crew was exemplary 🙂. The meals were wholesome and tasty. I have no complaints

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

Seated dude next to me even though lots of empty rows. But main thing was we sat on the tarmac after landing for 30 minutes because of, in the words of the dude who sat next to me, “operational incompetence”. We got changing directions about where to pick up gate checked bags. Pilot and flight attendant were awesome though.

The food was terrible this time. Otherwise pleasant, quiet, on-time.

It was a pretty standard flight... until the almost hour and a half spent on the taxi way. I get that the weather has been poor but the delay had nothing to do with the weather and more to do with a plane with several issues tying up the gate. I get that that happens from time to time but this has been EVERY flight I've been on for the past 5 years and I fly 3 to 5 times a year. This isn't just United... it's American, it's Delta. It's an issue with the entire industry. I work for UPS and packages on a cargo plane get better service than people do these days. Anymore I HATE flying.

Flight arrived 30 min early and bag was waiting at the baggage pickup. United Club HNL was one of the nicest in the system

Unfortunately weather delayed our flight waiting for our plane to arrive and due to a little snow time was needed to deice the plane so departure was very delayed and I missed the connecting flight

Very good. Because of the delays with my previous flight, I missed my connection, but I was able to book another flight through the United app easily.

I wish there were outlets to charge my iPhone. The crew was great; we had a female pilot who was great with explaining what was happening and delays,

The flight crew where really good. Better then the crew from BNE to SFO

Food should be changed in menu Many muslims travels in this airlime they need to add one Halal meal

Delayed, toilets did not flush, pilot parked to far away from Gate

My, Syed Zawar Hussein Shirazi frequently flyer membership number was not included on my boarding pass from O’Hare to Istanbul despite my reminder to the attendant at check in. Further she forgot to give me my boarding pass form Istanbul to Lahore and she needs to improve her customer service, please 🙏

Everything about that day was great I was happy with how things went as a first time traveling with the airline thank you for all that you’ve doing by taking us there to our various destinations thanks.

They oversold the tickets by one which was my ticket so I didn’t have a ticket till last second

Not good. I was supposed to be in Mint but got in economy class

Service was slow and checked bag was off last evening when flying business

Turkish Airline canceled our tickets in the very last minute, with our luggage and everything else, all prepared and good to go. It’s clear that they sold the tickets for better money to someone else. Bad, Bad, Bad business!!!

Awful seating. Bad food. Staff only have one bottle of water and no cans.

it was like a banya -so hot... They did provide a great experience with special food. one toilet broke midflight In general it was a peaceful and relaxing flight - for business class it was good.

Chicago to Istanbul was a much better experience than I expected since I’m more accustomed to Qatar Airways business class. The business lounge in the Istanbul airport was amazing - loved the lockers and phone charging stations, and the bathroom was a spa experience in itself. The onward leg from Istanbul to Karachi was utterly disappointing. Terrible plane, and I felt like I was in economy - the seats don’t come near to lying flat and the food was mediocre. What a sad downgrade - it isn’t as though the ticket on that leg was cheaper. So, on that front, there’s no contest with Qatar airways.

Second leg of Turkish Airline with Indigo is disaster for following reason. 1) You have to carry your cabin bags through ladder to boeing 777 because it was parked somewhere in parking lot and was not given a gate to board passengers and this seems to be people traveling to and fro from those flights and is not issue with flight itself. 2) I choose non vegetarian food on Turkish portal way ahead of checkin to entire trip, However the Indigo flight gave me random veg food saying they code veg food code from Turkish. 3) Indigo did not served any alcoholic beverages stating some weird reason which is non nonsensical. 4)Indigo have TV screens in front of you but it displays nothing except "Welcome Onboard" with annoying white black ground in dark flight. This is the most stupidest and annoying part because you are held hostage for 7 hours and only thing you could do is stare back at white screen which does not have entertainment package or even flight tracker. Such a shame.

Missed it by a couple minutes and couldn’t find an alternative flight so had to spend the night in DC and after much shuffling from 1 airline to another managed to get a United to Frankfurt.

There were only 2 toilets and one of them did not work in business class. We are not allowed to cross classes so had to wait in line to use the toilets!! The entertainment touch display was finicky and did not work all the time.

We missed our flight. There was not enough time built into the layover to get through immigration, customs, bagclaim, bag rechecking, and the long trip to another terminal and gate. Kayak really screwed up. We took the bus up to Wisconsin and then were picked up in Brookfield by private car. It was lucky we didnt miss the last bus out.

I tried both on line and by calling the Customer Service line to arrange for a special meal as i have food intolerances. I was under the impression from your service representative that I was successful. I was not. I cannot eat spicy foods and get very ill if i eat bell peppers. I could not eat either menu choice and no special meal was actually ordered. ( your representative tried to order it for a flight that did not have meal service!!! - found this out later). Your wonderful cabin crew managed to put together a fruit, salad, roll and cheese tray for me so I had something to eat. WHY WOULD YOU SERVE SPICY FOOD, WITH NO MILDER OPTION,ON AN INTERNATIONAL FLIGHT???

Crew was professional and great, flight was clean. However food was pathetic. I ordered a Hindu meal assuming no meat but they served chicken. Need to be very specific- Hindu meal should be categorize as Vegetarian - no meat or egg. Or it should be specific that we are serving meat.

Late flight Delays Poor service Poor staff Worst airline ever

Ground staff and cabin crew were excellent. Flight was perfectly on time. Zero issues.

Even after a delay, getting off the ground, thanks for keeping me safe, the airline made certain that my connecting flight was rebooked to get me to my final destination. It was actually rebooked twice, and my luggage still managed to meet me. The airline gave me a credit for food and beverage to be used at the airport vendors, regretfully, the credit did not transfer to my final boarding pass. Oh, well…

Trip was smooth, good drew, average meal, almost cold coffee. Excellent landing. Did not enjoy going down the stairs, walking to the gate, walking up the stairs, going a long walk to the exchange gate, and going down the stairs again to be bussed all the way where we originally landed to take our next flight! Over all an average experience. Thank you.

I booked extra leg room, due to seat neighbor i now consider extra shoulder and arm room as well. Seems like the seats shrink in width now The crew was very friendly and professional ( 100%). Food was good not great, breakfast was bad, a dry slice of bread would have been better. Facilities clean.

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