BOS - KGS

$706 Find Cheap Flights from Boston to Kos

This is the cheapest round-trip flight price found by a KAYAK user in the last 72 hours by searching for a flight from Boston to Kos departing on 10/21. 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

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

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Boston to Kos, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Boston to Kos, as well as popular online travel agencies
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Cheap Flights from Boston to Kos (BOS-KGS)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Boston to Kos 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 Kos

Tue, Oct 21 - Wed, Nov 5
Lufthansa Logo
8:05 pm - 7:05 pmBOS-KGS
16h 00m1 stop
Lufthansa Logo
6:55 pm - 6:35 pmKGS-BOS
30h 40m1 stop
$706Lufthansa
Find Deal
Tue, Oct 21 - Wed, Nov 5
SWISS Logo
5:05 pm - 7:55 pmBOS-KGS
19h 50m1 stop
SWISS Logo
2:30 pm - 8:20 pmKGS-BOS
36h 50m2 stops
$721SWISS
Find Deal
Wed, Oct 22 - Wed, Nov 5
Lufthansa Logo
10:00 pm - 6:40 pmBOS-KGS
13h 40m1 stop
Lufthansa Logo
6:55 pm - 6:35 pmKGS-BOS
30h 40m1 stop
$729Lufthansa
Find Deal
Wed, Oct 22 - Wed, Nov 5
Lufthansa Logo
8:05 pm - 6:40 pmBOS-KGS
15h 35m2 stops
Lufthansa Logo
6:55 pm - 6:35 pmKGS-BOS
30h 40m1 stop
$738Lufthansa
Find Deal
Tue, Oct 21 - Sat, Nov 8
Lufthansa Logo
8:05 pm - 7:05 pmBOS-KGS
16h 00m1 stop
Lufthansa Logo
8:15 pm - 6:35 pmKGS-BOS
29h 20m1 stop
$756Lufthansa
Find Deal
Wed, Oct 22 - Wed, Nov 5
Lufthansa Logo
8:05 pm - 6:40 pmBOS-KGS
15h 35m2 stops
Lufthansa Logo
6:55 pm - 1:25 pmKGS-BOS
25h 30m2 stops
$768Lufthansa
Find Deal
Thu, Oct 23 - Wed, Nov 5
SWISS Logo
5:05 pm - 3:10 pmBOS-KGS
15h 05m1 stop
SWISS Logo
2:30 pm - 8:20 pmKGS-BOS
36h 50m2 stops
$771SWISS
Find Deal
Wed, Oct 22 - Sat, Nov 8
Lufthansa Logo
5:50 pm - 6:40 pmBOS-KGS
17h 50m1 stop
Lufthansa Logo
8:15 pm - 6:35 pmKGS-BOS
29h 20m1 stop
$779Lufthansa
Find Deal
Tue, Oct 21 - Wed, Nov 5
Lufthansa Logo
5:50 pm - 7:05 pmBOS-KGS
18h 15m2 stops
Lufthansa Logo
6:55 pm - 1:25 pmKGS-BOS
25h 30m2 stops
$782Lufthansa
Find Deal
Tue, Oct 21 - Thu, Nov 6
Emirates Logo
11:05 pm - 5:30 pmBOS-KGS
35h 25m2 stops
Emirates Logo
12:35 pm - 1:55 pmKGS-BOS
32h 20m2 stops
$1,972Emirates
Find Deal

Everything you should know

Top airlines
Lufthansa
Cheapest • from $706 (round-trip)
SWISS
Best reviews • 7.5 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
Cheapest round-trip
$706
Lufthansa
Tue 10/21Wed 11/5
BOS - KGS • 1 stop
Cheapest one-way
Multiple Airlines
Mon 9/15
BOS - KGS • multi-stop
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KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to Kos!
Booking Insights

KAYAK's insights & trends for Boston to Kos flights

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

Which airlines provide the cheapest flights from Boston to Kos?

The cheapest round-trip price for the route for each airline clicked by KAYAK users in the last 72 hours.

In the past 3 days, the cheapest round-trip tickets from Boston to Kos were found on Lufthansa ($706) and SWISS ($721).

Good to know

Cheapest flight$706
Flight from Boston to Kos

When to book flights from Boston to Kos

Are your dates flexible? Find out the best times to travel from Boston to Kos 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 Kos

  • What is the cheapest flight from Boston to Kos?

    In the last 3 days, the lowest price for a flight from Boston to Kos was $706 for a round-trip ticket.

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

    Yes, you'll most likely have to show a valid passport before boarding the plane in Boston and on arrival in Kos.

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

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

  • Which airline alliances offer flights from Boston to Kos?

    Star Alliance is the only airline alliance operating flights between Boston and Kos.

  • Which is the best airline for flights from Boston to Kos, SWISS or Lufthansa?

    The two airlines most popular with KAYAK users for flights from Boston to Kos are SWISS and Lufthansa. With an average price for the route of $1,151 and an overall rating of 7.5, SWISS is the most popular choice. Lufthansa is also a great choice for the route, with an average price of $1,081 and an overall rating of 6.8.

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

    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 Kos.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Kos 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 Kos?

    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 Kos with an airline and back to Boston with another airline. Booking your flights between Boston and KGS 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 Kos?

    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 Kos from Boston up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top airlines flying from Boston to Kos

 
See real verified KAYAK customer reviews for airlines flying from Boston to Kos. 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 Kos? 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.
7.5
SWISSOverall score based on 1730 reviews
8.2Crew
7.7Boarding
6.8Entertainment
7.4Comfort
7.1Food
Airline reviews

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

10.0 ExcellentAnonymous, Sep 2025DEN - ZRH
Read more SWISS reviews

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

Horrible flight. First delay in boarding of approximately 30 minutes. While in the plane, the flight attendants huddle and we get an announcement that the crew's legal time was exceeded, that they don't have replacement crew and that they will need to cancel the flight. One would think that they would know that their time was to be exceeded BEFORE boarding. Took for ever to deplane. Then we were told that flight would not be cancelled but gave us a departure time of 21.15, which of course was not fulfilled. Arrived in Valencia, luggage took 30 minutes to arrive. Absolutely unacceptable

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

Zürich to Boston was great. Nice to Zurich was not bad

I can’t even the whole trip was a catastrophe

Poor. Seats uncomfortable. No leg room. Hot and humid the whole trip. Food and staffs were ok.

The seats were so close together, when the man in front of me put his seat back, the screen in front of me was 9 inches from my face. There is no way to lean forward if I needed to pick something up. It was pretty uncomfortable for a ten hour flight. I was very surprised.

The food was good. Most the staff was pleasant. The flight would be drastically improved with WiFi on a long international flight.

When I needed to get my bag off of the plane so that I could take a train because the connection was 4 hours later, they took 2 hours to take my bag off making me take the train and miss my flight simultaneously. The seat size on the plane is too small for an average aged woman let alone a middle-aged man. It's unacceptable and I will not fly Boeing again.

The cushion of the seats are old and very thin. The food can be more tasty or come with salt packages

I liked Quiet people around me. Crew could have helped people with overhead luggage so they aren't moving other peoples bags around and causing problems for people that had there bags there first

The flight and crew were good. The customer experience on the ground could have been better. We had to reschedule our flight because of a delay on the previous flight. The attendants working the desk in Washington DC were not helpful. They told us to scan a QR code and that would get us rebooked. Why couldn't two people standing at their computers do this? We had to chat with someone to get everything figured out. It was extremely confusing.

The plane was delayed by two hours in Chicago which led to us missing the next flight. Lufthansa rebooked the flight and booked us a hotel for the night in Frankfurt. The level of customer service and getting us taken care of was superb. The flight crew and the service on the ground was superb.

It was a short flight, everything was good with it.

Flight was delayed over one hour and I had to pay to select my seat, even though my booking supposedly had free selection (I paid extra for this at time of booking)

Stop charging for alcohol overseas flights and start taking cash again not everyone wants to pay with card if the person is bigger give him seat on the outside seats not the middle in between the people is common sense and mainly if you fly for Lufthansa provides the sam service and experience...

good entertainment package but rather small seats for business class

The male attendant has zero personality. It seemed like he was over worked or hated his job, not once did he smile or made any contact with the people on the plane. Strictly business and call it a day!

Booked Economy but it translated to economy light for Lufthansa so now we are stuck paying an extra $75 per person both ways for our checked bags. If I had known that, I would have never booked these tickets because it came out to be more than other options. The booking in the kayak side clearly says Economy and has a link to the inormation for Lufthansa which states Economy included a checked bag. Super annoyed about that.

The flight from Dulles to Munich was just okay. The seats were comfortable and extra foot room was noticeable in comfort plus. Disappointed in the booking in so much I requested an aisle seat and then was assigned a middle seat. The food was inedible. Movie choices were moderate. I usually fly Delta, but this WA flight was cheaper. Next time, I'll happily pay the extra to fly Delta.

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

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