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Cheap flights from Islip, New York to London from $918

This is the cheapest round-trip 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 5/5. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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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
5:38 pm - 10:00 am
ISP
-
LGW
35h 22m
1 stop
Multiple Airlines Logo
1:00 pm - 10:05 am
LGW
-
ISP
26h 05m
2 stops
$918Multiple Airlines
Tue, May 5 - Tue, May 12
Multiple Airlines Logo
5:38 pm - 10:00 am
ISP
-
LGW
35h 22m
1 stop
Multiple Airlines Logo
1:00 pm - 10:05 am
LGW
-
ISP
26h 05m
2 stops
$935Multiple Airlines
Tue, May 5 - Tue, May 12
Multiple Airlines Logo
4:07 pm - 11:55 pm
ISP
-
LGW
26h 48m
2 stops
Multiple Airlines Logo
2:00 pm - 11:00 am
LGW
-
ISP
26h 00m
1 stop
$1,014Multiple Airlines
Mon, May 4 - Mon, May 11
Multiple Airlines Logo
6:40 pm - 3:00 pm
ISP
-
LHR
39h 20m
2 stops
Multiple Airlines Logo
8:50 am - 5:44 pm
LHR
-
ISP
37h 54m
2 stops
$1,239Multiple Airlines
Tue, May 5 - Tue, May 12
Multiple Airlines Logo
6:40 pm - 5:20 pm
ISP
-
LHR
41h 40m
2 stops
Multiple Airlines Logo
7:40 am - 5:44 pm
LHR
-
ISP
39h 04m
2 stops
$1,274Multiple Airlines
Wed, May 6 - Wed, May 13
Multiple Airlines Logo
5:25 pm - 9:45 pm
ISP
-
LHR
47h 20m
2 stops
Multiple Airlines Logo
7:35 pm - 4:30 pm
LHR
-
ISP
49h 55m
2 stops
$1,287Multiple Airlines
Mon, May 4 - Mon, May 11
Multiple Airlines Logo
9:59 am - 6:45 am
ISP
-
LHR
15h 46m
1 stop
Multiple Airlines Logo
9:40 am - 7:45 pm
LHR
-
ISP
15h 05m
1 stop
$1,358Multiple Airlines
Tue, May 5 - Tue, May 12
Multiple Airlines Logo
9:59 am - 6:45 am
ISP
-
LHR
15h 46m
1 stop
Multiple Airlines Logo
9:40 am - 7:45 pm
LHR
-
ISP
15h 05m
1 stop
$1,414Multiple Airlines
Wed, May 6 - Wed, May 13
Multiple Airlines Logo
7:25 am - 6:45 am
ISP
-
LHR
18h 20m
1 stop
Multiple Airlines Logo
9:40 am - 4:10 pm
LHR
-
ISP
11h 30m
1 stop
$1,464Multiple Airlines
Mon, May 4 - Mon, May 11
Multiple Airlines Logo
12:30 pm - 6:30 am
ISP
-
LHR
13h 00m
1 stop
Multiple Airlines Logo
1:05 pm - 10:05 am
LHR
-
ISP
26h 00m
2 stops
$1,772Multiple Airlines
Tue, May 5 - Tue, May 12

momondo Fare Finder

 
Customize your flight search to find flights from Islip, New York to London 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 March 24, 2026.
Use the filters below to find and compare flights from Islip, New York to London that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

IslipLondon

ISP - LGW

ISPLGW

Islip Long Island

Tue 5/5

5:38 pm-10:00 am

1 stop35h 22m

London Gatwick

Tue 5/12

1:00 pm-10:05 am

2 stops26h 05m

$918

IslipLondon

ISP - LGW

ISPLGW

Islip Long Island

Tue 5/5

5:38 pm-10:00 am

1 stop35h 22m

London Gatwick

Tue 5/12

1:00 pm-10:05 am

2 stops26h 05m

$935

IslipLondon

ISP - LGW

ISPLGW

Islip Long Island

Mon 5/4

4:07 pm-11:55 pm

2 stops26h 48m

London Gatwick

Mon 5/11

2:00 pm-11:00 am

1 stop26h 00m

$1,014

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Tue 5/5

6:40 pm-3:00 pm

2 stops39h 20m

London Heathrow

Tue 5/12

8:50 am-5:44 pm

2 stops37h 54m

$1,239

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Wed 5/6

6:40 pm-5:20 pm

2 stops41h 40m

London Heathrow

Wed 5/13

7:40 am-5:44 pm

2 stops39h 04m

$1,274

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Mon 5/4

5:25 pm-9:45 pm

2 stops47h 20m

London Heathrow

Mon 5/11

7:35 pm-4:30 pm

2 stops49h 55m

$1,287

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Tue 5/5

9:59 am-6:45 am

1 stop15h 46m

London Heathrow

Tue 5/12

9:40 am-7:45 pm

1 stop15h 05m

$1,358

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Wed 5/6

9:59 am-6:45 am

1 stop15h 46m

London Heathrow

Wed 5/13

9:40 am-7:45 pm

1 stop15h 05m

$1,414
Quickest round-trip

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Mon 5/4

7:25 am-6:45 am

1 stop18h 20m

London Heathrow

Mon 5/11

9:40 am-4:10 pm

1 stop11h 30m

$1,464

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Tue 5/5

12:30 pm-6:30 am

1 stop13h 00m

London Heathrow

Tue 5/12

1:05 pm-10:05 am

2 stops26h 00m

$1,772

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 16 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

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?

The cheapest day to depart from Islip, New York to London is on a Wednesday. Travelers who choose to depart for London on a Wednesday will often find tickets for as low as $628. If your travel schedule is flexible, try to avoid departing on a Saturday because tickets tend to average around $691. These prices are subject to change though, so be sure to set up a Price Alert for flights to London.

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

Flying to London from Islip, New York in the morning is the least expensive time of day to depart. momondo users have found prices as low as $611 when looking at flights departing in the morning. Flights to London are more costly in the evening, with an average ticket price of $677. Departure times in the evening fall within the peak daily travel times, which is why tickets can be more expensive.

When to book flights from Islip, New York to London

Are you open to changing your travel dates? Check out the ideal times to fly from Islip, New York to London 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 (ISP to LON) flight deals and tips

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

Fastest flight time

20h 01m

Direct flights

None
The fastest flight from Islip, New York to London takes 20h 01m
There are no direct flights from Islip, New York to London. There are no popular flight routes from Islip, New York to London.
Search flight deals

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

    The distance between Islip Long Island and London is about 3425.8 mi. In terms of flight time, this usually takes a little over 20h 01m.

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

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

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

    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.

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

    The necessary travel and health documents for your London 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
Gatwick
Hounslow
Milton Keynes
Luton
Dover
Crawley
Slough
Wembley
Hayes
Croydon
Dartford
Brentwood
Guildford
Harrow
Cobham
Folkestone
Romford
Stansted
Watford
Richmond

Why use momondo?

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

momondo collates all your flight options in one place and lets you filter them to find the perfect flight from Islip to London. momondo saves you time and could save you money on your trip.

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

All flight searches from Islip to London on momondo can be filtered to show those which offer flexible booking policies.

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

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 Islip to London.

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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Find better results for your trip to the United Kingdom

Fly into one of these airports located in London

Airports listed have a maximum distance of 35.6 mi from London
London City Airport
London Gatwick Airport
London Heathrow Airport
London Luton Airport
London Southend Airport
London Stansted Airport