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Cheap flights from Islip, New York to London from $664

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Islip, New York to London departing on 7/5. 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

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Find the cheapest flights from Islip, New York to London

Cheap round-trip flights

Enter your travel dates to find the best prices.
Multiple Airlines Logo
11:31 am - 5:20 pm
ISP
-
LHR
24h 49m
2 stops
Multiple Airlines Logo
2:20 pm - 11:47 pm
LHR
-
ISP
38h 27m
2 stops
$1,487Multiple Airlines
Sun, Jul 19 - Sun, Jul 26
Multiple Airlines Logo
2:22 pm - 1:55 pm
ISP
-
LHR
18h 33m
2 stops
Multiple Airlines Logo
2:20 pm - 10:41 am
LHR
-
ISP
49h 21m
2 stops
$1,538Multiple Airlines
Sat, Jul 4 - Fri, Jul 10
Multiple Airlines Logo
11:31 am - 6:20 pm
ISP
-
LHR
25h 49m
2 stops
Multiple Airlines Logo
7:40 am - 11:53 pm
LHR
-
ISP
21h 13m
2 stops
$1,567Multiple Airlines
Fri, Jul 17 - Fri, Jul 24
Multiple Airlines Logo
1:45 pm - 1:30 pm
ISP
-
LHR
18h 45m
2 stops
Multiple Airlines Logo
4:50 pm - 10:41 am
LHR
-
ISP
46h 51m
2 stops
$1,614Multiple Airlines
Sat, Jul 11 - Sat, Jul 18
Multiple Airlines Logo
1:45 pm - 4:00 pm
ISP
-
LHR
21h 15m
2 stops
Multiple Airlines Logo
7:40 pm - 10:41 am
LHR
-
ISP
44h 01m
2 stops
$1,615Multiple Airlines
Sat, Jul 11 - Sat, Jul 18
Multiple Airlines Logo
9:00 am - 9:00 pm
ISP
-
LHR
31h 00m
2 stops
Multiple Airlines Logo
7:40 am - 12:30 pm
LHR
-
ISP
33h 50m
3 stops
$1,688Multiple Airlines
Sat, Jul 11 - Sat, Jul 18
Multiple Airlines Logo
7:00 am - 6:30 am
ISP
-
LHR
18h 30m
3 stops
Multiple Airlines Logo
7:40 am - 12:30 pm
LHR
-
ISP
33h 50m
3 stops
$1,700Multiple Airlines
Sat, Jul 11 - Sat, Jul 18
Multiple Airlines Logo
5:29 pm - 9:35 am
ISP
-
LHR
11h 06m
1 stop
Multiple Airlines Logo
7:40 am - 6:35 pm
LHR
-
ISP
15h 55m
2 stops
$1,722Multiple Airlines
Fri, Jul 17 - Fri, Jul 24
Multiple Airlines Logo
5:29 pm - 9:40 am
ISP
-
LHR
11h 11m
1 stop
Multiple Airlines Logo
10:05 am - 8:59 pm
LHR
-
ISP
15h 54m
1 stop
$1,774Multiple Airlines
Sun, Jul 19 - Sun, Jul 26
Multiple Airlines Logo
3:05 pm - 12:00 pm
ISP
-
LHR
15h 55m
2 stops
Multiple Airlines Logo
10:05 am - 10:30 am
LHR
-
ISP
29h 25m
1 stop
$1,778Multiple Airlines
Sat, Jul 11 - Sat, Jul 18

momondo Fare Finder

 
Customize your flight search to find flights from Islip, New York to London Heathrow Airport 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 6, 2026.
Use the filters below to find and compare flights from Islip, New York to London Heathrow Airport that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Sun 7/19

11:31 am-5:20 pm

2 stops24h 49m

London Heathrow

Sun 7/26

2:20 pm-11:47 pm

2 stops38h 27m

$1,487

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Sat 7/4

2:22 pm-1:55 pm

2 stops18h 33m

London Heathrow

Fri 7/10

2:20 pm-10:41 am

2 stops49h 21m

$1,538

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Fri 7/17

11:31 am-6:20 pm

2 stops25h 49m

London Heathrow

Fri 7/24

7:40 am-11:53 pm

2 stops21h 13m

$1,567

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Sat 7/11

1:45 pm-1:30 pm

2 stops18h 45m

London Heathrow

Sat 7/18

4:50 pm-10:41 am

2 stops46h 51m

$1,614

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Sat 7/11

1:45 pm-4:00 pm

2 stops21h 15m

London Heathrow

Sat 7/18

7:40 pm-10:41 am

2 stops44h 01m

$1,615

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Sat 7/11

9:00 am-9:00 pm

2 stops31h 00m

London Heathrow

Sat 7/18

7:40 am-12:30 pm

3 stops33h 50m

$1,688

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Sat 7/11

7:00 am-6:30 am

3 stops18h 30m

London Heathrow

Sat 7/18

7:40 am-12:30 pm

3 stops33h 50m

$1,700
Quickest round-trip

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Fri 7/17

5:29 pm-9:35 am

1 stop11h 06m

London Heathrow

Fri 7/24

7:40 am-6:35 pm

2 stops15h 55m

$1,722

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Sun 7/19

5:29 pm-9:40 am

1 stop11h 11m

London Heathrow

Sun 7/26

10:05 am-8:59 pm

1 stop15h 54m

$1,774

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Sat 7/11

3:05 pm-12:00 pm

2 stops15h 55m

London Heathrow

Sat 7/18

10:05 am-10:30 am

1 stop29h 25m

$1,778

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 14 resultsSorted by cheapest first
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See travel insights to London from

How to get the cheapest flight ticket from Islip, New York to London Heathrow Airport

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 day to depart on your flight to London Heathrow Airport?

Our data shows that Wednesday is the least expensive day to fly to London Heathrow Airport. Tickets to fly out on this day can be as low as $669. The most expensive day to fly to London Heathrow Airport is Saturday, with ticket prices averaging around $731.

What is the cheapest time of day to depart on your flight to London Heathrow Airport?

According to our data, the cheapest time of day to fly to London Heathrow Airport is in the morning. momondo users have found flights departing from Islip, New York to London Heathrow Airport in the morning for as low as $646. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. Flights in the evening are often more expensive with an average ticket price of $722.

When to book flights from Islip, New York to London Heathrow Airport

Are you open to changing your travel dates? Check out the ideal times to fly from Islip, New York to London Heathrow Airport according to our flight data. Find out which month and days have the cheapest flights.
Estimated round-trip price

Cheap Islip, New York to London Heathrow Airport (ISP to LHR) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Islip, New York to London Heathrow Airport

Fastest flight time

17h 18m

Direct flights

None
The fastest flight from Islip, New York to London Heathrow Airport takes 17h 18m
There are no direct flights from Islip, New York to London Heathrow Airport. There are no popular flight routes from Islip, New York to London Heathrow Airport.
Search flight deals

Frequently asked questions about flying from Islip, New York to London Heathrow Airport

  • How far is Islip Long Island to London Heathrow by plane?

    A flight from Islip Long Island to London Heathrow will travel around 3412.8 mi. Typically, this will take 17h 18m by plane in normal conditions.

  • When did momondo last update prices for flights from Islip Long Island Airport to London Heathrow Airport?

    Prices for flights from Islip Long Island Airport to London Heathrow Airport are refreshed on a daily basis.

  • How old do you have to be to fly from Islip Long Island Airport to London Heathrow Airport?

    The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Islip Long Island Airport to London Heathrow Airport.

  • What documentation or ID do you need to fly to London Heathrow Airport?

    The necessary travel and health documents for your London Heathrow 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.

Traveling to a place near London?

Book flights to London if you plan to visit one of these locations
Hounslow
Gatwick
Milton Keynes
Luton
Dover
Hayes
Crawley
Croydon
Wembley
Stratford-upon-Avon
Stansted
Slough
Harrow
Brentwood
Watford
Cobham
Guildford
Folkestone
Uxbridge
Romford

Why use momondo?

Why should I use momondo to find a flight deal from Islip to London?

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 London from Islip.

Can I find flights from Islip to London with flexible booking policies on momondo?

Yes. momondo enables you to select and highlight flights to London from Islip with this policy.

How can momondo help me find flights from Islip to London?

momondo provides multiple filters to help you find the best flight to London from Islip. Filter by price, airline, airports, cabin, aircraft, payment method, number of stops and more.

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

Yes. momondo can track prices for Islip to London flights and alert you when they change. Perform a search to set up the price alert. All that is required is a valid email address.

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