In terms of precipitation, rainfall in London ranges from 1.6 - 2.8 inches per month. January is typically the wettest month, when rainfall can reach 2.8 in. July is typically the driest time to visit London when rainfall is around 1.6 in.

If weather is an important factor for your trip to London, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 62.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 39.2 F).

How far in advance should I book a flight from Islip to London?

To save up to 22% on this flight, we recommend booking at least 31 days prior to travel. The price may fluctuate and will likely increase closer to your departure date. Users on Cheapflights have found tickets from Islip to London from $617 1-2 weeks out and tickets from $654 for flights departing within the next 72 hours.

What is the cheapest month to fly from Islip to London?

January can be a great time to fly to London from Islip with a flight ticket averaging about $561. Cheapflights users have found deals in the month of January for as cheap as $375. The most expensive prices can be found in the month of December.

What is the cheapest time of day to fly from ISP to LON?

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Islip to London as you normally would.

What airport do you fly from for flights from Islip to London?

For a flight from Islip to London, you will be flying from Long Island. Islip Long Island (ISP) is just 7.2 mi from the center of the city. Long Island is the only Islip airport and it handles 0 outbound flights to London per day. 0 airlines have flights to London from Islip Long Island on a regular basis.

Can I find deals for flights from Islip to London that include hotel bookings?

Yes. In addition to deals on Islip to London flights, Cheapflights offers vacation packages that include both flights and hotel.

How can I find direct flights from Islip to London?

After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Islip to London.

Can I find deals for business class flights from Islip to London?

Yes. Cheapflights offers flight deals from Islip to London by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

$654+ Cheap Flights from Islip to London

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Cheap flight deals from Islip to London

Round-trip from	$654 (Kiwi.com)
Popular in	December
Cheapest in	January
Average price	$515

From Islip Long Island to London (LON)

Search Deals

High demand for flights, 3% potential price rise

Search Deals

Cheapest flight prices on average. 2% potential price decrease ($12 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in September 2025

Search Deals

Find flight deals from Islip to London

Cheapest flights from Islip to London
Explore the most affordable flight options available from Islip to London. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 11, 2025.

Fri 10/104:58 pmISP - LGW

1 stop36h 02mMultiple Airlines

Tue 10/142:00 pmLGW - ISP

1 stop25h 57mMultiple Airlines

Deal found 9/11

$654

Thu 12/42:19 pmISP - LGW

2 stops15h 36mMultiple Airlines

Sun 12/142:10 pmLGW - ISP

2 stops25h 26mMultiple Airlines

Deal found 9/10

$1,030

Thu 12/411:53 amISP - LHR

2 stops16h 22mMultiple Airlines

Sun 12/148:50 amLHR - ISP

2 stops16h 11mMultiple Airlines

Deal found 9/10

$1,045

Fri 10/104:33 pmISP - LHR

2 stops32h 57mMultiple Airlines

Tue 10/146:00 amLHR - ISP

2 stops19h 01mMultiple Airlines

Deal found 9/11

$1,627

Fri 12/52:19 pmISP - LHR

2 stops15h 06mMultiple Airlines

Sun 12/148:00 amLHR - ISP

2 stops17h 01mMultiple Airlines

Deal found 9/10

$6,215

Best flights from Islip to London
Discover carefully curated flight deals from Islip to London that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 11, 2025.

Fri 10/104:58 pmISP - LGW

1 stop36h 02mMultiple Airlines

Tue 10/142:00 pmLGW - ISP

1 stop25h 57mMultiple Airlines

Deal found 9/11

$654

Thu 12/42:19 pmISP - LGW

2 stops15h 36mMultiple Airlines

Sun 12/142:10 pmLGW - ISP

2 stops25h 26mMultiple Airlines

Deal found 9/10

$1,030

Thu 12/411:53 amISP - LHR

2 stops16h 22mMultiple Airlines

Sun 12/148:50 amLHR - ISP

2 stops16h 11mMultiple Airlines

Deal found 9/10

$1,045

Fri 10/104:33 pmISP - LHR

2 stops32h 57mMultiple Airlines

Tue 10/146:00 amLHR - ISP

2 stops19h 01mMultiple Airlines

Deal found 9/11

$1,627

Fri 12/52:19 pmISP - LHR

2 stops15h 06mMultiple Airlines

Sun 12/148:00 amLHR - ISP

2 stops17h 01mMultiple Airlines

Deal found 9/10

$6,215

Last-minute flights from Islip to London
Discover last-minute flight deals from Islip to London. Data last updated September 11, 2025 and is based on user searches.

Fri 10/104:58 pmISP - LGW

1 stop36h 02mMultiple Airlines

Tue 10/142:00 pmLGW - ISP

1 stop25h 57mMultiple Airlines

Deal found 9/11

$654

Fri 10/104:33 pmISP - LHR

2 stops32h 57mMultiple Airlines

Tue 10/146:00 amLHR - ISP

2 stops19h 01mMultiple Airlines

Deal found 9/11

$1,627

Fly from

Fly to

Route

Depart

Return

Price

IslipLondon

ISP - LGW

ISPLGW

Islip Long Island

Fri 10/10

4:58 pm-10:00 am

1 stop36h 02m

London Gatwick

Tue 10/14

2:00 pm-10:57 am

1 stop25h 57m

$654

IslipLondon

ISP - LGW

ISPLGW

Islip Long Island

Thu 12/4

2:19 pm-10:55 am

2 stops15h 36m

London Gatwick

Sun 12/14

2:10 pm-10:36 am

2 stops25h 26m

$1,030

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Thu 12/4

11:53 am-9:15 am

2 stops16h 22m

London Heathrow

Sun 12/14

8:50 am-8:01 pm

2 stops16h 11m

$1,045

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Fri 10/10

4:33 pm-6:30 am

2 stops32h 57m

London Heathrow

Tue 10/14

6:00 am-8:01 pm

2 stops19h 01m

$1,627

IslipLondon

ISP - LHR

ISPLHR

Islip Long Island

Fri 12/5

2:19 pm-10:25 am

2 stops15h 06m

London Heathrow

Sun 12/14

8:00 am-8:01 pm

2 stops17h 01m

$6,215

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/11

Best time to book a flight from Islip to London

Have a flexible travel schedule? Discover the best time to fly to London from Islip with our price prediction graph.

Estimated round-trip price

Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Islip to London

What is the cheapest month to book a flight from Islip to London?

Currently, November is the cheapest month in which you can book a flight from Islip to London (average of $661). Flying from Islip to London in June is currently the most expensive (average of $1,098). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

Related info for your journey

What airport do you fly from for flights from Islip to London?
For a flight from Islip to London, you will be flying from Long Island. Islip Long Island (ISP) is just 7.2 mi from the center of the city. Long Island is the only Islip airport and it handles 0 outbound flights to London per day. 0 airlines have flights to London from Islip Long Island on a regular basis.
Can I find deals for flights from Islip to London that include hotel bookings?
Yes. In addition to deals on Islip to London flights, Cheapflights offers vacation packages that include both flights and hotel.
How can I find direct flights from Islip to London?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Islip to London.
Can I find deals for business class flights from Islip to London?
Yes. Cheapflights offers flight deals from Islip to London by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.
What is the cheapest month to book a flight from Islip to London?
Currently, November is the cheapest month in which you can book a flight from Islip to London (average of $661). Flying from Islip to London in June is currently the most expensive (average of $1,098). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

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$654+ Cheap flights from Islip (ISP) to London (LON)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 10/10. Fares are subject to change and may not be available on all flights or dates of travel.

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Cheap flight deals from Islip to London

Round-trip from

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Average price

Find flight deals from Islip to London

Cheapest flights from Islip to LondonExplore the most affordable flight options available from Islip to London. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 11, 2025.

Explore the most affordable flight options available from Islip to London. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 11, 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from Islip to London that are best for you.

Best time to book a flight from Islip to London

Have a flexible travel schedule? Discover the best time to fly to London from Islip with our price prediction graph.

Cheapflights Insights

Everything you need to know about your flight from Islip to London

What is the cheapest month to book a flight from Islip to London?

Related info for your journey

Find useful and relevant information for your journey from Islip to London. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

What airport do you fly from for flights from Islip to London?

Can I find deals for flights from Islip to London that include hotel bookings?

How can I find direct flights from Islip to London?

Can I find deals for business class flights from Islip to London?

What is the cheapest month to book a flight from Islip to London?

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Cheapest flights from Islip to London
Explore the most affordable flight options available from Islip to London. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 11, 2025.