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Cheap flights from Boston to Kos from $336

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Boston to Kos departing on 10/22. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
1 adult
1 adult, Economy, 0 bags

Discover deals from 900+ travel sites with momondo.

Find the cheapest flights from Boston to Kos

Cheap round-trip flights

Enter your travel dates to find the best prices.
SWISS Logo
5:10 pm - 7:40 pm
BOS
-
KGS
19h 30m
1 stop
SWISS Logo
11:00 am - 3:10 pm
KGS
-
BOS
35h 10m
1 stop
$857SWISS
Mon, Aug 24 - Mon, Aug 31
Multiple Airlines Logo
5:10 pm - 7:40 pm
BOS
-
KGS
19h 30m
1 stop
Multiple Airlines Logo
8:50 pm - 9:27 pm
KGS
-
BOS
31h 37m
2 stops
$862Multiple Airlines
Mon, Aug 24 - Mon, Aug 31
Multiple Airlines Logo
6:50 pm - 8:50 pm
BOS
-
KGS
43h 00m
2 stops
Multiple Airlines Logo
8:50 pm - 9:27 pm
KGS
-
BOS
31h 37m
2 stops
$872Multiple Airlines
Mon, Aug 24 - Mon, Aug 31
Multiple Airlines Logo
8:50 pm - 10:15 am
BOS
-
KGS
30h 25m
3 stops
Multiple Airlines Logo
8:50 pm - 9:45 pm
KGS
-
BOS
31h 55m
3 stops
$905Multiple Airlines
Mon, Aug 24 - Mon, Aug 31
Multiple Airlines Logo
3:35 pm - 9:05 pm
BOS
-
KGS
22h 30m
2 stops
Multiple Airlines Logo
6:10 pm - 8:20 pm
KGS
-
BOS
33h 10m
3 stops
$950Multiple Airlines
Mon, Aug 24 - Mon, Aug 31
Multiple Airlines Logo
8:50 pm - 7:35 am
BOS
-
KGS
27h 45m
3 stops
Multiple Airlines Logo
12:40 pm - 2:02 pm
KGS
-
BOS
32h 22m
3 stops
$1,050Multiple Airlines
Fri, Sep 25 - Sat, Oct 3
Multiple Airlines Logo
10:50 am - 8:30 pm
BOS
-
KGS
26h 40m
2 stops
Multiple Airlines Logo
12:40 pm - 2:02 pm
KGS
-
BOS
32h 22m
3 stops
$1,056Multiple Airlines
Fri, Sep 25 - Sat, Oct 3
Multiple Airlines Logo
8:05 pm - 7:45 pm
BOS
-
KGS
16h 40m
1 stop
Multiple Airlines Logo
8:45 pm - 7:55 pm
KGS
-
BOS
30h 10m
1 stop
$1,119Multiple Airlines
Fri, Sep 25 - Sat, Oct 3
Multiple Airlines Logo
3:35 pm - 7:35 pm
BOS
-
KGS
21h 00m
2 stops
Multiple Airlines Logo
8:45 pm - 7:55 pm
KGS
-
BOS
30h 10m
1 stop
$1,139Multiple Airlines
Fri, Sep 25 - Sat, Oct 3
Multiple Airlines Logo
5:45 am - 8:40 pm
BOS
-
KGS
31h 55m
3 stops
Multiple Airlines Logo
11:00 pm - 8:20 pm
KGS
-
BOS
28h 20m
2 stops
$1,218Multiple Airlines
Fri, Jul 3 - Mon, Jul 20

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SWISS flights from Boston to Kos

Our best SWISS deals on Boston to Kos flight tickets
SWISS
Aug 24
BOS5:10 pmBoston Logan Intl
19h 30m
1 stop
KGS7:40 pmKos
Aug 31
KGS11:00 amKos
35h 10m
1 stop
BOS3:10 pmBoston Logan Intl
$857
SWISS
Jul 3
BOS5:10 pmBoston Logan Intl
19h 50m
1 stop
KGS8:00 pmKos
Jul 20
KGS11:00 amKos
35h 10m
1 stop
BOS3:10 pmBoston Logan Intl
$2,525

Lufthansa flights from Boston to Kos

Our best Lufthansa deals on Boston to Kos flight tickets
Lufthansa
Jun 30
BOS8:05 pmBoston Logan Intl
16h 00m
1 stop
KGS7:05 pmKos
Aug 31
KGS9:45 amKos
12h 55m
1 stop
BOS3:40 pmBoston Logan Intl
$2,607
Lufthansa
Jun 30
BOS8:05 pmBoston Logan Intl
16h 00m
1 stop
KGS7:05 pmKos
Aug 31
KGS9:45 amKos
12h 55m
1 stop
BOS3:40 pmBoston Logan Intl
$2,608
Lufthansa
Jun 30
BOS9:25 amBoston Logan Intl
26h 40m
2 stops
KGS7:05 pmKos
Aug 31
KGS9:45 amKos
21h 14m
3 stops
BOS11:59 pmBoston Logan Intl
$2,800

momondo 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, momondo users made 832,500 searches. Data last updated June 24, 2026.
Use the filters below to find and compare flights from Boston to Kos that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

BostonKos

BOS - KGS

BOSKGS

Boston Logan Intl

Mon 8/24

5:10 pm-7:40 pm

1 stop19h 30m

Kos

Mon 8/31

11:00 am-3:10 pm

1 stop35h 10m

$857

BostonKos

BOS - KGS

BOSKGS

Boston Logan Intl

Mon 8/24

5:10 pm-7:40 pm

1 stop19h 30m

Kos

Mon 8/31

8:50 pm-9:27 pm

2 stops31h 37m

$862

BostonKos

BOS - KGS

BOSKGS

Boston Logan Intl

Mon 8/24

6:50 pm-8:50 pm

2 stops43h 00m

Kos

Mon 8/31

8:50 pm-9:27 pm

2 stops31h 37m

$872

BostonKos

BOS - KGS

BOSKGS

Boston Logan Intl

Mon 8/24

8:50 pm-10:15 am

3 stops30h 25m

Kos

Mon 8/31

8:50 pm-9:45 pm

3 stops31h 55m

$905

BostonKos

BOS - KGS

BOSKGS

Boston Logan Intl

Mon 8/24

3:35 pm-9:05 pm

2 stops22h 30m

Kos

Mon 8/31

6:10 pm-8:20 pm

3 stops33h 10m

$950

BostonKos

BOS - KGS

BOSKGS

Boston Logan Intl

Fri 9/25

8:50 pm-7:35 am

3 stops27h 45m

Kos

Sat 10/3

12:40 pm-2:02 pm

3 stops32h 22m

$1,050

BostonKos

BOS - KGS

BOSKGS

Boston Logan Intl

Fri 9/25

10:50 am-8:30 pm

2 stops26h 40m

Kos

Sat 10/3

12:40 pm-2:02 pm

3 stops32h 22m

$1,056
Quickest round-trip

BostonKos

BOS - KGS

BOSKGS

Boston Logan Intl

Fri 9/25

8:05 pm-7:45 pm

1 stop16h 40m

Kos

Sat 10/3

8:45 pm-7:55 pm

1 stop30h 10m

$1,119

BostonKos

BOS - KGS

BOSKGS

Boston Logan Intl

Fri 9/25

3:35 pm-7:35 pm

2 stops21h 00m

Kos

Sat 10/3

8:45 pm-7:55 pm

1 stop30h 10m

$1,139

BostonKos

BOS - KGS

BOSKGS

Boston Logan Intl

Fri 7/3

5:45 am-8:40 pm

3 stops31h 55m

Kos

Mon 7/20

11:00 pm-8:20 pm

2 stops28h 20m

$1,218

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first
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2

See travel insights to Kos from

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

What is the cheapest airline that flies from Boston Logan Intl to Kos?

SWISS and Brussels Airlines are the most popular carriers operating from Boston Logan Intl to Kos

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

Fastest flight time

16h 00m

Direct flights

None
The fastest flight from Boston to Kos takes 16h 00m
There are no direct flights from Boston to Kos. There are no popular flight routes from Boston to Kos.
Search flight deals

Frequently asked questions about flying from Boston to Kos

  • 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 16h 00m.

  • 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?

  • 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?

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
SWISSPriceFrom $954Free CancellationRating
7.5
1,972 reviews
Search SWISS flights

Traveling to a place near Kos?

Book flights to Kos if you plan to visit one of these locations
Kardamena
Marmari

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.

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