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$1,175+ Cheap flights from Boston (BOS) to Kos (KGS)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 7/26. Fares are subject to change and may not be available on all flights or dates of travel.
BOS — KGS
Jun 17 — Jun 241
Tue 6/17
Tue 6/24
1 adult, Economy
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Cheap 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 June 12, 2025.

Round-trip from

$1,175
(Brussels Airlines)
From Boston Logan Intl to Kos
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Find flight deals from Boston to Kos

Cheapest flights from Boston to Kos
Explore the most affordable flight options available from Boston to Kos. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 12, 2025.

This Brussels Airlines deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Brussels Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/268:05 pmBOS - KGS
2 stops31h 20mBrussels Airlines
Sat 8/28:35 pmKGS - BOS
2 stops28h 05mBrussels Airlines
Deal found 6/11$1,175
This SWISS deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure SWISS is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/265:05 pmBOS - KGS
1 stop34h 05mSWISS
Sat 8/28:45 pmKGS - BOS
1 stop30h 10mSWISS
Deal found 6/11$1,426

Cheapflights Fare Finder

Customize your flight search to find flights from Boston to Kos that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated June 12, 2025.
Use the filters below to find and compare flights from Boston to Kos that are best for you.

Fly from

Boston

Fly to

Kos

Route

Depart

Return

Price

BostonKos

BOS - KGS

BOSKGS

Boston Logan Intl

Sat 7/26

8:05 pm-10:25 am

2 stops31h 20m

Kos

Sat 8/2

8:35 pm-5:40 pm

2 stops28h 05m

$1,175

BostonKos

BOS - KGS

BOSKGS

Boston Logan Intl

Sat 7/26

5:05 pm-10:10 am

1 stop34h 05m

Kos

Sat 8/2

8:45 pm-7:55 pm

1 stop30h 10m

$1,426

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/11

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.

Cheapflights Insights

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

Rainfall in Kos by month

Plan your trip to Kos by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Kos ranges from 0.1 - 6.7 inches per month. January is typically the wettest month, when rainfall can reach 6.7 in. July is typically the driest time to visit Kos when rainfall is around 0.1 in.

Temperature in Kos by month

Plan your trip to Kos by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Kos, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 78.8 F. Travelers looking to avoid the cold should look outside of February, when temperatures are typically at their lowest (around 50.0 F).

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 June 12, 2025.
SWISS
7.5
Good
1,623 reviews

Entertainment

6.7

Boarding

7.6

Comfort

7.4

Food

7.0

Overall

7.5

Crew

8.2

Reviews

1 / 20
6.0
Good

Yvette,Nov 2024

ZRH - ATH

The website is difficult to navigate. You pay for everything. The carry on baggage policy is complicated. The food choices were poor and the seat was uncomfortable.
SWISS
7.5
Good
1,623 reviews
SWISS
7.5
Good
1,623 reviews

Entertainment

6.7

Boarding

7.6

Comfort

7.4

Food

7.0

Overall

7.5

Crew

8.2

Reviews

1 / 20
6.0
Good

Yvette,Nov 2024

ZRH - ATH

The website is difficult to navigate. You pay for everything. The carry on baggage policy is complicated. The food choices were poor and the seat was uncomfortable.
Brussels Airlines
7.4
Good
355 reviews
SWISS
7.5
Good
1,623 reviews

Entertainment

6.7

Boarding

7.6

Comfort

7.4

Food

7.0

Overall

7.5

Crew

8.2

Reviews

1 / 20
6.0
Good

Yvette,Nov 2024

ZRH - ATH

The website is difficult to navigate. You pay for everything. The carry on baggage policy is complicated. The food choices were poor and the seat was uncomfortable.

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 $1,175. Another airline that can offer you cheap pricing is SWISS.

  • 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.

See more FAQs

Browse thousands of different options on Cheapflights for your next trip

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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 June 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
SWISSCheapest$928Average$1,151FlexibilityNo cancel feeOn-time79%
LufthansaCheapest$981Average$1,159FlexibilityNo cancel feeOn-time76%

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