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Cheap flights from Islip, New York to London from $435

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 7/21. 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

Find the cheapest flights from Islip, New York to London

Cheap round-trip flights

Enter your travel dates to find the best prices.
JetBlue Logo
2:00 pm - 8:45 pm
ISP
-
LHR
49h 45m
2 stops
JetBlue Logo
8:15 am - 9:35 pm
LHR
-
ISP
42h 20m
2 stops
$1,238JetBlue
Thu, Oct 1 - Thu, Oct 8
Multiple Airlines Logo
10:00 am - 8:20 pm
ISP
-
LHR
29h 20m
2 stops
Multiple Airlines Logo
9:50 am - 8:15 pm
LHR
-
ISP
15h 25m
2 stops
$1,300Multiple Airlines
Wed, Jul 29 - Wed, Aug 5
Multiple Airlines Logo
2:11 pm - 6:45 am
ISP
-
LHR
11h 34m
1 stop
Multiple Airlines Logo
1:25 pm - 1:30 pm
LHR
-
ISP
29h 05m
2 stops
$1,332Multiple Airlines
Wed, Jul 29 - Wed, Aug 5
Multiple Airlines Logo
4:45 pm - 11:55 am
ISP
-
LHR
14h 10m
2 stops
Multiple Airlines Logo
8:50 am - 8:15 pm
LHR
-
ISP
16h 25m
2 stops
$1,336Multiple Airlines
Thu, Jul 30 - Thu, Aug 6
Multiple Airlines Logo
2:11 pm - 6:45 am
ISP
-
LHR
11h 34m
1 stop
Multiple Airlines Logo
9:50 am - 8:15 pm
LHR
-
ISP
15h 25m
2 stops
$1,414Multiple Airlines
Tue, Jul 28 - Tue, Aug 4
Multiple Airlines Logo
2:22 pm - 8:05 am
ISP
-
LHR
36h 43m
2 stops
Multiple Airlines Logo
7:40 am - 11:46 pm
LHR
-
ISP
21h 06m
2 stops
$1,468Multiple Airlines
Sat, Jul 4 - Fri, Jul 10
Multiple Airlines Logo
2:11 pm - 7:10 am
ISP
-
LHR
11h 59m
1 stop
Multiple Airlines Logo
9:50 am - 8:15 pm
LHR
-
ISP
15h 25m
2 stops
$1,498Multiple Airlines
Thu, Oct 1 - Thu, Oct 8
Multiple Airlines Logo
7:26 am - 7:10 am
ISP
-
LHR
18h 44m
1 stop
Multiple Airlines Logo
2:30 pm - 8:15 pm
LHR
-
ISP
10h 45m
1 stop
$1,532Multiple Airlines
Thu, Oct 1 - Thu, Oct 8
Multiple Airlines Logo
2:22 pm - 8:05 am
ISP
-
LHR
36h 43m
2 stops
Multiple Airlines Logo
7:40 am - 11:46 pm
LHR
-
ISP
21h 06m
2 stops
$1,550Multiple Airlines
Sat, Jul 4 - Fri, Jul 10
Multiple Airlines Logo
4:45 pm - 7:10 am
ISP
-
LHR
9h 25m
1 stop
Multiple Airlines Logo
5:35 pm - 12:30 pm
LHR
-
ISP
23h 55m
1 stop
$1,655Multiple Airlines
Thu, Jul 30 - Thu, Aug 6

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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 16, 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

Thu 10/1

2:00 pm-8:45 pm

2 stops49h 45m

London Heathrow

Thu 10/8

8:15 am-9:35 pm

2 stops42h 20m

$1,238

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Wed 7/29

10:00 am-8:20 pm

2 stops29h 20m

London Heathrow

Wed 8/5

9:50 am-8:15 pm

2 stops15h 25m

$1,300

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Wed 7/29

2:11 pm-6:45 am

1 stop11h 34m

London Heathrow

Wed 8/5

1:25 pm-1:30 pm

2 stops29h 05m

$1,332

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Thu 7/30

4:45 pm-11:55 am

2 stops14h 10m

London Heathrow

Thu 8/6

8:50 am-8:15 pm

2 stops16h 25m

$1,336
Quickest round-trip

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Tue 7/28

2:11 pm-6:45 am

1 stop11h 34m

London Heathrow

Tue 8/4

9:50 am-8:15 pm

2 stops15h 25m

$1,414

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Sat 7/4

2:22 pm-8:05 am

2 stops36h 43m

London Heathrow

Fri 7/10

7:40 am-11:46 pm

2 stops21h 06m

$1,468

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Thu 10/1

2:11 pm-7:10 am

1 stop11h 59m

London Heathrow

Thu 10/8

9:50 am-8:15 pm

2 stops15h 25m

$1,498

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Thu 10/1

7:26 am-7:10 am

1 stop18h 44m

London Heathrow

Thu 10/8

2:30 pm-8:15 pm

1 stop10h 45m

$1,532

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Sat 7/4

2:22 pm-8:05 am

2 stops36h 43m

London Heathrow

Fri 7/10

7:40 am-11:46 pm

2 stops21h 06m

$1,550

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Thu 7/30

4:45 pm-7:10 am

1 stop9h 25m

London Heathrow

Thu 8/6

5:35 pm-12:30 pm

1 stop23h 55m

$1,655

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 15 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 $688. The most expensive day to fly to London Heathrow Airport is Saturday, with ticket prices averaging around $741.

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 $661. 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 $734.

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

12h 46m

Direct flights

None
The fastest flight from Islip, New York to London Heathrow Airport takes 12h 46m
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 12h 46m 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
Stansted
Stratford-upon-Avon
Harrow
Slough
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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