Which layover airport offers the lowest fares from Boston to Kos?

Flights via Frankfurt am Main (FRA) offer the lowest average round-trip price of $1,130.

Which layover airport has the shortest travel time from Boston to Kos?

Flights connecting via Frankfurt am Main (FRA) have the shortest average one-way travel time: 13h 34m.

Which airport is the most popular layover for flights between Boston and Kos?

Frankfurt am Main (FRA) was the most common stop: 68% of momondo users choosing 1-stop flights on this route connected there.

Which layover airport has the shortest connection time from Boston to Kos?

Frankfurt am Main (FRA) has the shortest average layover time for this route: 2h 40m.

When did momondo last update prices for flights from Boston Logan Intl Airport to Kos Airport?

Prices for flights from Boston Logan Intl Airport to Kos Airport are refreshed on a daily basis.

How many operators does momondo search for flights from Boston Logan Intl Airport to Kos Airport?

As of September 2025, there are 2 operators available to choose from for flights from Boston Logan Intl Airport to Kos Airport.

How old do you have to be to fly from Boston Logan Intl Airport to Kos Airport?

The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Boston Logan Intl Airport to Kos Airport.

What documentation or ID do you need to fly to Kos Airport?

The necessary travel and health documents for your Kos Airport trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.

$706 Cheap Flights from Boston to Kos in 2025/26

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Find the cheapest flights from Boston to Kos

Round-trip

One-way

Cheap round-trip flights

8:05 pm - 7:05 pmBOS-KGS

16h 00m1 stop

6:55 pm - 6:35 pmKGS-BOS

30h 40m1 stop

$706Lufthansa

Find Deal

Tue, Oct 21 - Wed, Nov 5

5:05 pm - 7:55 pmBOS-KGS

19h 50m1 stop

2:30 pm - 8:20 pmKGS-BOS

36h 50m2 stops

$721SWISS

Find Deal

Tue, Oct 21 - Wed, Nov 5

10:00 pm - 6:40 pmBOS-KGS

13h 40m1 stop

6:55 pm - 6:35 pmKGS-BOS

30h 40m1 stop

$729Lufthansa

Find Deal

Wed, Oct 22 - Wed, Nov 5

8:05 pm - 6:40 pmBOS-KGS

15h 35m2 stops

6:55 pm - 6:35 pmKGS-BOS

30h 40m1 stop

$738Lufthansa

Find Deal

Wed, Oct 22 - Wed, Nov 5

8:05 pm - 7:05 pmBOS-KGS

16h 00m1 stop

8:15 pm - 6:35 pmKGS-BOS

29h 20m1 stop

$756Lufthansa

Find Deal

Tue, Oct 21 - Sat, Nov 8

8:05 pm - 6:40 pmBOS-KGS

15h 35m2 stops

6:55 pm - 1:25 pmKGS-BOS

25h 30m2 stops

$768Lufthansa

Find Deal

Wed, Oct 22 - Wed, Nov 5

5:05 pm - 3:10 pmBOS-KGS

15h 05m1 stop

2:30 pm - 8:20 pmKGS-BOS

36h 50m2 stops

$771SWISS

Find Deal

Thu, Oct 23 - Wed, Nov 5

5:50 pm - 6:40 pmBOS-KGS

17h 50m1 stop

8:15 pm - 6:35 pmKGS-BOS

29h 20m1 stop

$779Lufthansa

Find Deal

Wed, Oct 22 - Sat, Nov 8

11:05 pm - 5:30 pmBOS-KGS

35h 25m2 stops

12:35 pm - 1:55 pmKGS-BOS

32h 20m2 stops

$1,972Emirates

Find Deal

Tue, Oct 21 - Thu, Nov 6

11:05 pm - 5:30 pmBOS-KGS

35h 25m2 stops

12:35 pm - 1:55 pmKGS-BOS

32h 20m2 stops

$2,015Emirates

Find Deal

Wed, Oct 22 - Thu, Nov 6

Lufthansa flights from Boston to Kos

Our best Lufthansa deals on Boston to Kos flight tickets

Lufthansa

Oct 21

BOS8:05 pmBoston Logan Intl

16h 00m

1 stop

KGS7:05 pmKos

Nov 5

KGS6:55 pmKos

30h 40m

1 stop

BOS6:35 pmBoston Logan Intl

$706

Find similar

Lufthansa

Oct 22

BOS10:00 pmBoston Logan Intl

13h 40m

1 stop

KGS6:40 pmKos

Nov 5

KGS6:55 pmKos

30h 40m

1 stop

BOS6:35 pmBoston Logan Intl

$729

Find similar

Lufthansa

Oct 22

BOS8:05 pmBoston Logan Intl

15h 35m

2 stops

KGS6:40 pmKos

Nov 5

KGS6:55 pmKos

30h 40m

1 stop

BOS6:35 pmBoston Logan Intl

$738

Find similar

SWISS flights from Boston to Kos

Our best SWISS deals on Boston to Kos flight tickets

SWISS

Oct 21

BOS5:05 pmBoston Logan Intl

19h 50m

1 stop

KGS7:55 pmKos

Nov 5

KGS2:30 pmKos

36h 50m

2 stops

BOS8:20 pmBoston Logan Intl

$721

Find similar

SWISS

Oct 23

BOS5:05 pmBoston Logan Intl

15h 05m

1 stop

KGS3:10 pmKos

Nov 5

KGS2:30 pmKos

36h 50m

2 stops

BOS8:20 pmBoston Logan Intl

$771

Find similar

Fly from

Fly to

Route

Depart

Return

Price

BostonKos

BOS - KGS

BOSKGS

Boston Logan Intl

Tue 10/21

8:05 pm-7:05 pm

1 stop16h 00m

Kos

Wed 11/5

6:55 pm-6:35 pm

1 stop30h 40m

$706

BostonKos

BOS - KGS

BOSKGS

Boston Logan Intl

Tue 10/21

5:05 pm-7:55 pm

1 stop19h 50m

Kos

Wed 11/5

2:30 pm-8:20 pm

2 stops36h 50m

$721

BostonKos

BOS - KGS

BOSKGS

Boston Logan Intl

Wed 10/22

10:00 pm-6:40 pm

1 stop13h 40m

Kos

Wed 11/5

6:55 pm-6:35 pm

1 stop30h 40m

$729

BostonKos

BOS - KGS

BOSKGS

Boston Logan Intl

Wed 10/22

8:05 pm-6:40 pm

2 stops15h 35m

Kos

Wed 11/5

6:55 pm-6:35 pm

1 stop30h 40m

$738

BostonKos

BOS - KGS

BOSKGS

Boston Logan Intl

Tue 10/21

8:05 pm-7:05 pm

1 stop16h 00m

Kos

Sat 11/8

8:15 pm-6:35 pm

1 stop29h 20m

$756

BostonKos

BOS - KGS

BOSKGS

Boston Logan Intl

Wed 10/22

8:05 pm-6:40 pm

2 stops15h 35m

Kos

Wed 11/5

6:55 pm-1:25 pm

2 stops25h 30m

$768

BostonKos

BOS - KGS

BOSKGS

Boston Logan Intl

Thu 10/23

5:05 pm-3:10 pm

1 stop15h 05m

Kos

Wed 11/5

2:30 pm-8:20 pm

2 stops36h 50m

$771

BostonKos

BOS - KGS

BOSKGS

Boston Logan Intl

Wed 10/22

5:50 pm-6:40 pm

1 stop17h 50m

Kos

Sat 11/8

8:15 pm-6:35 pm

1 stop29h 20m

$779

BostonKos

BOS - KGS

BOSKGS

Boston Logan Intl

Tue 10/21

11:05 pm-5:30 pm

2 stops35h 25m

Kos

Thu 11/6

12:35 pm-1:55 pm

2 stops32h 20m

$1,972

BostonKos

BOS - KGS

BOSKGS

Boston Logan Intl

Wed 10/22

11:05 pm-5:30 pm

2 stops35h 25m

Kos

Thu 11/6

12:35 pm-1:55 pm

2 stops32h 20m

$2,015

Flights are sorted by cheapest round-trip flights first.

Sorted by cheapest first

How to get the cheapest flight ticket from Boston to Kos

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

Prices

Layovers

What is the cheapest day to depart on your flight to Kos?

The cheapest day to depart from Boston to Kos is on a Saturday when prices can be found for as low as $1,035. On the other hand, Monday is the most expensive day to depart from Boston because it is more convenient for both business and leisure travelers. As a result, prices tend to be around $1,398.

What is the cheapest time of day to depart on your flight to Kos?

Flying to Kos from Boston in the evening is the least expensive time of day to depart. momondo users have found prices as low as $1,202 when looking at flights departing in the evening. If you have a flexible travel schedule, then try to avoid flying in the afternoon when prices are $1,219 on average. Flights to Kos from Boston in the afternoon are generally more expensive because this time of day is more convenient for travelers’ schedules.

When to book flights from Boston to Kos

Are you open to changing your travel dates? Check out the ideal times to fly from Boston to Kos according to our flight data. Find out which month and days have the cheapest flights.

Estimated round-trip price

Cheap Boston to Kos (BOS to KGS) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Boston to Kos

Direct flights	None

There are no direct flights from Boston to Kos. There are no popular flight routes from Boston to Kos.

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How far is Boston Logan Intl to Kos by plane?
The distance between Boston Logan Intl and Kos is about 4930.9 mi. By plane, this route typically takes 11h 50m.
When did momondo last update prices for flights from Boston Logan Intl Airport to Kos Airport?
Prices for flights from Boston Logan Intl Airport to Kos Airport are refreshed on a daily basis.
How many operators does momondo search for flights from Boston Logan Intl Airport to Kos Airport?
As of September 2025, there are 2 operators available to choose from for flights from Boston Logan Intl Airport to Kos Airport.
How old do you have to be to fly from Boston Logan Intl Airport to Kos Airport?
The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Boston Logan Intl Airport to Kos Airport.
What documentation or ID do you need to fly to Kos Airport?
The necessary travel and health documents for your Kos Airport trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.
What is the most popular airline from Boston to Kos?
Based on momondo bookings for this flight route, the most popular airline on flight routes from Boston to Kos is Lufthansa (60% of total bookings). The next most popular airline is SWISS (40%).

Best airlines flying from Boston to Kos

Compare and see reviews for airlines that fly from Boston to Kos with momondo

Airline	Rating	Free Cancellation	Price
SWISS	PriceFrom $954	Free Cancellation	Rating 7.6 1,737 reviews		Search SWISS flights
Lufthansa	PriceFrom $981	Free Cancellation	Rating 6.8 7,407 reviews		Search Lufthansa flights

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Why use momondo?

Why should I use momondo to find a flight deal from Boston to Kos?

To find the flight that best suits your needs, momondo gathers a range of flights from a large pool of different airlines and agents; you can then use our insights and filters to find and book the right flight to Kos from Boston.

Can I find flights from Boston to Kos with flexible booking policies on momondo?

Yes. momondo enables you to select and highlight flights to Kos from Boston with this policy.

How can momondo help me find flights from Boston to Kos?

momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from Boston to Kos.

I’m not ready to book a flight from Boston to Kos right now. Can momondo alert me if prices change?

If you are not ready to book a flight from Boston to Kos now, use our insights above to find helpful tips or alternatively set up a price alert, where momondo will track prices on flights to Kos and let you know when they change.