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Kos

Cheap flights from Boston (BOS) to Kos (KGS)

BOS — KGS
Jan 11 — Jan 181
Sun 1/11
Sun 1/18
1 adult, Economy
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Find flight deals from Boston to Kos

Discover tips and strategies to find the most affordable flight options for your journey from Boston (BOS) to Kos (KGS). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated December 12, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
1 star
Provider with most accurate pricing for Boston Logan Intl-Kos flight deals.
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Provider most trusted by Cheapflights users for Boston Logan Intl-Kos flights.
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  • Most accurate provider: When it comes to deals on Boston-Kos flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Boston-Kos flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Boston-Kos flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Boston-Kos flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Boston-Kos flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Boston to Kos

Have a flexible travel schedule? Discover the best time to fly to Kos from Boston with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Reviews of airlines servicing Kos

Get insights into the airlines that provide service to Kos. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Kos. Reviews last updated December 12, 2025.
Read reviews from past customers who have flown SWISS and Lufthansa from Boston to Kos. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
SWISS
7.5
Good
1,810 reviews

Comfort

7.4

Boarding

7.7

Food

7.1

Crew

8.3

Entertainment

6.8

Overall

7.5

Reviews

1 / 20
2.0
Mediocre

Katerina,Sep 2025

GVA - ATH

Although the plane was half empty and the flight was late at night, we were not allowed to change seats/ use empty seats to get ourselves more comfortable, or get some proper sleep. It is really frustrating to see lack of flexibility in such a simple need.
SWISS
7.5
Good
1,810 reviews
SWISS
7.5
Good
1,810 reviews

Comfort

7.4

Boarding

7.7

Food

7.1

Crew

8.3

Entertainment

6.8

Overall

7.5

Reviews

1 / 20
2.0
Mediocre

Katerina,Sep 2025

GVA - ATH

Although the plane was half empty and the flight was late at night, we were not allowed to change seats/ use empty seats to get ourselves more comfortable, or get some proper sleep. It is really frustrating to see lack of flexibility in such a simple need.
Lufthansa
6.8
Okay
7,626 reviews
SWISS
7.5
Good
1,810 reviews

Comfort

7.4

Boarding

7.7

Food

7.1

Crew

8.3

Entertainment

6.8

Overall

7.5

Reviews

1 / 20
2.0
Mediocre

Katerina,Sep 2025

GVA - ATH

Although the plane was half empty and the flight was late at night, we were not allowed to change seats/ use empty seats to get ourselves more comfortable, or get some proper sleep. It is really frustrating to see lack of flexibility in such a simple need.

Related info for your journey

Find useful and relevant information for your journey from Boston to Kos. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What are the cheapest airlines flying from Boston to Kos round-trip?

    Cheapflights users have booked flights from Boston to Kos round-trip from $954. Another airline that can offer you cheap pricing is Lufthansa.

  • Can I find deals for flights from Boston to Kos that include hotel bookings?

    Yes. In addition to deals on Boston to Kos flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Boston to Kos?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Boston to Kos.

  • Can I find deals for business class flights from Boston to Kos?

    Yes. Cheapflights offers flight deals from Boston to Kos by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

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Top 2 airlines flying from Boston to Kos

Discover the top 2 airlines that operate flights from Boston to Kos. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated December 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
SWISSCheapest$954Average$1,111FlexibilityNo cancel feeOn-time79%
LufthansaCheapest$999Average$1,269FlexibilityNo cancel feeOn-time76%

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