Find Cheap Flights from Islip Long Island to London (ISP - LON)

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FAQs for Booking Islip Long Island to London Flights

How long does a flight from Islip Long Island to London take?
An average nonstop flight takes 12h 10m, covering a distance of 3420 miles.
Which airlines provide the cheapest flights from Islip Long Island to London?
In the past 3 days, the cheapest round-trip tickets were found on Multiple Airlines ($663), American Airlines ($725) and Finnair ($729).
Do I need a passport to fly between Islip Long Island and London?
Yes.
What’s the cheapest day of the week to fly Islip Long Island to London?
For Islip Long Island to London, Wednesday is the cheapest day to fly on average and Thursday is the most expensive. Flying from London back to Islip Long Island, the best deals are generally found on Monday, with Friday being the most expensive.

Book cheap flights from Islip Long Island to London (round-trip)

Airports
Origin
Islip
$663
only
$663
Destination
London
$663
only
$663
Wed, Jan 24
ISP
LHR
29h 25m
Thu, Jan 25
LHR
ISP
29h 52m
Trip: 2 days
Overall 0.0 Poor
Based on 0 reviews
Wed, Jan 10
ISP
LHR
15h 00m
Fri, Jan 19
LHR
ISP
19h 09m
Trip: 10 days
7.2GoodShow reviews
Overall 7.2 Good
Based on 25860 reviews
Overall
7.3
Boarding
7.5
Comfort
7.1
Crew
7.8
Entertainment
6.7
Food
6.6
MIA
SFO
Excellent 8.6

No personal TV for entertainment

DCA
TPA
Excellent 8.6

The cabin crew was great at boarding and organizing the overhead bin space. Also, ground staff didn’t start check roll aboards before the overheads bins were full. There is nothing more frustrating than getting on after forced to gate check your bag to empty bin space (ahem, United at SFO).

Couldn’t get the entertainment to work.

EWR
CLT
Good 7.0

Smooth flying and lots of respects to the pilots for their dedicated work. The entertainment really works very well.

Poor Service. The service of drinks is done very poorly. Really concerned with the attitude. Never need those complimentary drinks.

CLT
PWM
Okay 5.0

All the different prices for seats. I think it is a stupid system. Miss the good old days of air travel.

SWF
PHL
Excellent 10.0

great stable flight

my connecting flight left late

Thu, Apr 5
ISP
LHR
19h 25m
Wed, Apr 11
LHR
ISP
15h 22m
Trip: 7 days
7.7GoodShow reviews
Overall 7.7 Good
Based on 2789 reviews
Overall
7.9
Boarding
8.0
Comfort
7.5
Crew
8.3
Entertainment
7.3
Food
7.2
JFK
HEL
Good 6.3

Food was all right because the flight didn't depart from Finland and catering was from a non-Finnish supplier. Hurrah!

Stewardesses announced that only chicken is available, regardless of any special meal requests (vegetarian etc..). Eventually special meals were located, but not before passengers specifically demanding for them. WTF. Finnair generously pours you a half an glass of wine with meal, for anything more you have to pay for. Supposedly you can buy snacks with money, but there were no menus or pricelists to be found in the seat pockets. Touchscreen functions were barely working on my entertainment screen, the remote control didn't work altogether. WIFI didn't work at all.

HKG
HEL
Excellent 10.0

Most Improved Player - Finnair has done the best experience in overall long haul flights out of the 40plus airlines I have flown in the last 3 years; brand new planes, nice and diverse cabin crew, beautiful lightings videos details chocolates etc, best entertainment system in the industry, and things always go smooth in Helsinki airport. Awesome imrpovement over recent years.

Big struggle for airlines still remains varying quality customer service. Finnair still seems to struggle with this occasionally. Finnair can work harder to keep customer service quality high. Hate to say it, but perhaps letting the bitter, last generation flight attendants who seem to have a grudge about the decline of the glamour and benefits of the job as flying has become commonplace with more competition (seen this on Finnair & N America’s older airlines line United)

ARN
HEL
Excellent 10.0

The service, the comfort of the plane. Great communication about turbulence.

TXL
HEL
Excellent 8.0

They have no charging points for the phone

HEL
JFK
Okay 4.0

UNCOMFORTABLE BED AND SERVICE

BED, DRINKS

Tue, Jan 23
ISP
LHR
36h 05m
Thu, Jan 25
LHR
ISP
52h 18m
Trip: 3 days
Overall 0.0 Poor
Based on 0 reviews
Thu, Jan 11
ISP
LHR
13h 25m
Sat, Jan 20
LHR
ISP
18h 59m
Trip: 10 days
7.2GoodShow reviews
Overall 7.2 Good
Based on 25860 reviews
Overall
7.3
Boarding
7.5
Comfort
7.1
Crew
7.8
Entertainment
6.7
Food
6.6
EWR
CLT
Good 7.0

Smooth flying and lots of respects to the pilots for their dedicated work. The entertainment really works very well.

Poor Service. The service of drinks is done very poorly. Really concerned with the attitude. Never need those complimentary drinks.

MIA
SFO
Excellent 8.6

No personal TV for entertainment

CZM
MIA
Good 6.3

The planes were on time. On our way down to Cozumel. The pilot let me 4-year-old son see the cockpit. Which was AWESOME, they were great As well as the flight crew on the way down. The trip down was terrific, If AA had this level of service all the time I would fly with them all the time.

The trip home was more of what i expected from AA. The check-in process was slow and i was overcharged for my bike, On the way down it was $25 the same price as previous AA flights, On other airlines, it also just counts as a piece of luggage. On the way home i was charged $150 oversized luggage, yet it was <50 lbs and within the size limits. The flight crew was not overall friendly. Very business like and not warm at all. If they were a restaurant i would not be returning. The locks on my bike case were both broken off. the case was not locked. Nor was this done by TSA as they would have left a note as they have previously done.

IND
CLT
Good 6.8

I did like that "new plane" smell. Good pretzels.

Plane was too new; computer system hadn't been set right. Left 45 minutes late, though made up some lost time in the air. Very rude passengers (obviously not the airline's fault, I know). Everyone thinks they should be the first to get off the plane!

SWF
PHL
Excellent 10.0

great stable flight

my connecting flight left late

Wed, Jan 24
ISP
LHR
29h 25m
Fri, Jan 26
LHR
ISP
33h 33m
Trip: 3 days
Overall 0.0 Poor
Based on 0 reviews
Fri, Jan 12
ISP
LHR
12h 10m
Sat, Jan 20
LHR
ISP
28h 27m
Trip: 9 days
7.2GoodShow reviews
Overall 7.2 Good
Based on 25860 reviews
Overall
7.3
Boarding
7.5
Comfort
7.1
Crew
7.8
Entertainment
6.7
Food
6.6
CZM
MIA
Good 6.3

The planes were on time. On our way down to Cozumel. The pilot let me 4-year-old son see the cockpit. Which was AWESOME, they were great As well as the flight crew on the way down. The trip down was terrific, If AA had this level of service all the time I would fly with them all the time.

The trip home was more of what i expected from AA. The check-in process was slow and i was overcharged for my bike, On the way down it was $25 the same price as previous AA flights, On other airlines, it also just counts as a piece of luggage. On the way home i was charged $150 oversized luggage, yet it was <50 lbs and within the size limits. The flight crew was not overall friendly. Very business like and not warm at all. If they were a restaurant i would not be returning. The locks on my bike case were both broken off. the case was not locked. Nor was this done by TSA as they would have left a note as they have previously done.

DCA
TPA
Excellent 8.6

The cabin crew was great at boarding and organizing the overhead bin space. Also, ground staff didn’t start check roll aboards before the overheads bins were full. There is nothing more frustrating than getting on after forced to gate check your bag to empty bin space (ahem, United at SFO).

Couldn’t get the entertainment to work.

DCA
LGA
Okay 4.6

Good crew on board

Poor communication, continued delays of flight. Poor on ground staff at dca

MIA
SFO
Excellent 8.6

No personal TV for entertainment

MLB
CLT
Okay 5.6

pleasant crew

CRJ900 is a small plane. no WiFi

Mon, Jan 22
ISP
LHR
41h 12m
Thu, Jan 25
LHR
ISP
52h 18m
Trip: 4 days
Overall 0.0 Poor
Based on 0 reviews
Sat, Jan 13
ISP
LHR
15h 00m
Sat, Jan 20
LHR
ISP
28h 27m
Trip: 8 days
7.2GoodShow reviews
Overall 7.2 Good
Based on 25860 reviews
Overall
7.3
Boarding
7.5
Comfort
7.1
Crew
7.8
Entertainment
6.7
Food
6.6
SWF
PHL
Excellent 10.0

great stable flight

my connecting flight left late

CLT
PWM
Okay 5.0

All the different prices for seats. I think it is a stupid system. Miss the good old days of air travel.

DCA
TPA
Excellent 8.6

The cabin crew was great at boarding and organizing the overhead bin space. Also, ground staff didn’t start check roll aboards before the overheads bins were full. There is nothing more frustrating than getting on after forced to gate check your bag to empty bin space (ahem, United at SFO).

Couldn’t get the entertainment to work.

BNA
DFW
Mediocre 3.3

Flight on time.

I miss friendly Southwest. Even the assigned seat is kit enough for me to use AA again. People smile at Southwest and seem to enjoy their job.

CZM
MIA
Good 6.3

The planes were on time. On our way down to Cozumel. The pilot let me 4-year-old son see the cockpit. Which was AWESOME, they were great As well as the flight crew on the way down. The trip down was terrific, If AA had this level of service all the time I would fly with them all the time.

The trip home was more of what i expected from AA. The check-in process was slow and i was overcharged for my bike, On the way down it was $25 the same price as previous AA flights, On other airlines, it also just counts as a piece of luggage. On the way home i was charged $150 oversized luggage, yet it was <50 lbs and within the size limits. The flight crew was not overall friendly. Very business like and not warm at all. If they were a restaurant i would not be returning. The locks on my bike case were both broken off. the case was not locked. Nor was this done by TSA as they would have left a note as they have previously done.

Mon, Jan 22
ISP
LHR
41h 12m
Wed, Jan 24
LHR
ISP
29h 52m
Trip: 3 days
Overall 0.0 Poor
Based on 0 reviews
Sun, Jan 14
ISP
LHR
19h 30m
Sat, Jan 20
LHR
ISP
28h 27m
Trip: 7 days
7.2GoodShow reviews
Overall 7.2 Good
Based on 25860 reviews
Overall
7.3
Boarding
7.5
Comfort
7.1
Crew
7.8
Entertainment
6.7
Food
6.6
CZM
MIA
Good 6.3

The planes were on time. On our way down to Cozumel. The pilot let me 4-year-old son see the cockpit. Which was AWESOME, they were great As well as the flight crew on the way down. The trip down was terrific, If AA had this level of service all the time I would fly with them all the time.

The trip home was more of what i expected from AA. The check-in process was slow and i was overcharged for my bike, On the way down it was $25 the same price as previous AA flights, On other airlines, it also just counts as a piece of luggage. On the way home i was charged $150 oversized luggage, yet it was <50 lbs and within the size limits. The flight crew was not overall friendly. Very business like and not warm at all. If they were a restaurant i would not be returning. The locks on my bike case were both broken off. the case was not locked. Nor was this done by TSA as they would have left a note as they have previously done.

MLB
CLT
Okay 5.6

pleasant crew

CRJ900 is a small plane. no WiFi

MIA
SFO
Excellent 8.6

No personal TV for entertainment

DCA
SDF
Good 6.0

Potable water was down so no coffee, tea, or more important... water to wash hands. Then they didn’t have my second choice of beverages after coffee either.

DCA
LGA
Okay 4.6

Good crew on board

Poor communication, continued delays of flight. Poor on ground staff at dca

Tue, Jan 23
ISP
LHR
36h 05m
Fri, Jan 26
LHR
ISP
33h 33m
Trip: 4 days
Overall 0.0 Poor
Based on 0 reviews
Mon, Jan 22
ISP
LHR
13h 25m
Wed, Jan 31
LHR
ISP
14h 52m
Trip: 10 days
7.2GoodShow reviews
Overall 7.2 Good
Based on 25860 reviews
Overall
7.3
Boarding
7.5
Comfort
7.1
Crew
7.8
Entertainment
6.7
Food
6.6
ORD
RDU
Good 7.0

Landed on time. AA is mostly on or before schedule. Definitely like that part. Smooth flying as well.

No interactions with the crew this time. Boarding is okay.

MIA
SFO
Excellent 8.6

No personal TV for entertainment

SWF
PHL
Excellent 10.0

great stable flight

my connecting flight left late

IND
CLT
Good 6.8

I did like that "new plane" smell. Good pretzels.

Plane was too new; computer system hadn't been set right. Left 45 minutes late, though made up some lost time in the air. Very rude passengers (obviously not the airline's fault, I know). Everyone thinks they should be the first to get off the plane!

CZM
MIA
Good 6.3

The planes were on time. On our way down to Cozumel. The pilot let me 4-year-old son see the cockpit. Which was AWESOME, they were great As well as the flight crew on the way down. The trip down was terrific, If AA had this level of service all the time I would fly with them all the time.

The trip home was more of what i expected from AA. The check-in process was slow and i was overcharged for my bike, On the way down it was $25 the same price as previous AA flights, On other airlines, it also just counts as a piece of luggage. On the way home i was charged $150 oversized luggage, yet it was <50 lbs and within the size limits. The flight crew was not overall friendly. Very business like and not warm at all. If they were a restaurant i would not be returning. The locks on my bike case were both broken off. the case was not locked. Nor was this done by TSA as they would have left a note as they have previously done.

Mon, Jan 22
ISP
LHR
41h 12m
Fri, Jan 26
LHR
ISP
33h 33m
Trip: 5 days
Overall 0.0 Poor
Based on 0 reviews
Tue, Jan 23
ISP
LHR
13h 25m
Thu, Feb 1
LHR
ISP
19h 54m
Trip: 10 days
7.2GoodShow reviews
Overall 7.2 Good
Based on 25860 reviews
Overall
7.3
Boarding
7.5
Comfort
7.1
Crew
7.8
Entertainment
6.7
Food
6.6
DCA
LGA
Okay 4.6

Good crew on board

Poor communication, continued delays of flight. Poor on ground staff at dca

BNA
DFW
Mediocre 3.3

Flight on time.

I miss friendly Southwest. Even the assigned seat is kit enough for me to use AA again. People smile at Southwest and seem to enjoy their job.

MLB
CLT
Okay 5.6

pleasant crew

CRJ900 is a small plane. no WiFi

SWF
PHL
Excellent 10.0

great stable flight

my connecting flight left late

DCA
TPA
Excellent 8.6

The cabin crew was great at boarding and organizing the overhead bin space. Also, ground staff didn’t start check roll aboards before the overheads bins were full. There is nothing more frustrating than getting on after forced to gate check your bag to empty bin space (ahem, United at SFO).

Couldn’t get the entertainment to work.

Wed, Jan 24
ISP
LHR
15h 00m
Fri, Feb 2
LHR
ISP
14h 07m
Trip: 10 days
7.2GoodShow reviews
Overall 7.2 Good
Based on 25860 reviews
Overall
7.3
Boarding
7.5
Comfort
7.1
Crew
7.8
Entertainment
6.7
Food
6.6
CLT
PWM
Okay 5.0

All the different prices for seats. I think it is a stupid system. Miss the good old days of air travel.

DCA
TPA
Excellent 8.6

The cabin crew was great at boarding and organizing the overhead bin space. Also, ground staff didn’t start check roll aboards before the overheads bins were full. There is nothing more frustrating than getting on after forced to gate check your bag to empty bin space (ahem, United at SFO).

Couldn’t get the entertainment to work.

ORD
RDU
Good 7.0

Landed on time. AA is mostly on or before schedule. Definitely like that part. Smooth flying as well.

No interactions with the crew this time. Boarding is okay.

MLB
CLT
Okay 5.6

pleasant crew

CRJ900 is a small plane. no WiFi

BNA
DFW
Mediocre 3.3

Flight on time.

I miss friendly Southwest. Even the assigned seat is kit enough for me to use AA again. People smile at Southwest and seem to enjoy their job.

Thu, Jan 25
ISP
LHR
13h 25m
Sat, Feb 3
LHR
ISP
18h 59m
Trip: 10 days
7.2GoodShow reviews
Overall 7.2 Good
Based on 25860 reviews
Overall
7.3
Boarding
7.5
Comfort
7.1
Crew
7.8
Entertainment
6.7
Food
6.6
EWR
CLT
Good 7.0

Smooth flying and lots of respects to the pilots for their dedicated work. The entertainment really works very well.

Poor Service. The service of drinks is done very poorly. Really concerned with the attitude. Never need those complimentary drinks.

CLT
PWM
Okay 5.0

All the different prices for seats. I think it is a stupid system. Miss the good old days of air travel.

IND
CLT
Good 6.8

I did like that "new plane" smell. Good pretzels.

Plane was too new; computer system hadn't been set right. Left 45 minutes late, though made up some lost time in the air. Very rude passengers (obviously not the airline's fault, I know). Everyone thinks they should be the first to get off the plane!

DCA
LGA
Okay 4.6

Good crew on board

Poor communication, continued delays of flight. Poor on ground staff at dca

MIA
SFO
Excellent 8.6

No personal TV for entertainment

Fri, Jan 26
ISP
LHR
13h 25m
Sat, Feb 3
LHR
ISP
18h 59m
Trip: 9 days
7.2GoodShow reviews
Overall 7.2 Good
Based on 25860 reviews
Overall
7.3
Boarding
7.5
Comfort
7.1
Crew
7.8
Entertainment
6.7
Food
6.6
EWR
CLT
Good 7.0

Smooth flying and lots of respects to the pilots for their dedicated work. The entertainment really works very well.

Poor Service. The service of drinks is done very poorly. Really concerned with the attitude. Never need those complimentary drinks.

SWF
PHL
Excellent 10.0

great stable flight

my connecting flight left late

IND
CLT
Good 6.8

I did like that "new plane" smell. Good pretzels.

Plane was too new; computer system hadn't been set right. Left 45 minutes late, though made up some lost time in the air. Very rude passengers (obviously not the airline's fault, I know). Everyone thinks they should be the first to get off the plane!

ORD
RDU
Good 7.0

Landed on time. AA is mostly on or before schedule. Definitely like that part. Smooth flying as well.

No interactions with the crew this time. Boarding is okay.

DCA
LGA
Okay 4.6

Good crew on board

Poor communication, continued delays of flight. Poor on ground staff at dca

Sat, Jan 27
ISP
LHR
12h 10m
Sat, Feb 3
LHR
ISP
18h 59m
Trip: 8 days
7.2GoodShow reviews
Overall 7.2 Good
Based on 25860 reviews
Overall
7.3
Boarding
7.5
Comfort
7.1
Crew
7.8
Entertainment
6.7
Food
6.6
BNA
DFW
Mediocre 3.3

Flight on time.

I miss friendly Southwest. Even the assigned seat is kit enough for me to use AA again. People smile at Southwest and seem to enjoy their job.

CLT
PWM
Okay 5.0

All the different prices for seats. I think it is a stupid system. Miss the good old days of air travel.

IND
CLT
Good 6.8

I did like that "new plane" smell. Good pretzels.

Plane was too new; computer system hadn't been set right. Left 45 minutes late, though made up some lost time in the air. Very rude passengers (obviously not the airline's fault, I know). Everyone thinks they should be the first to get off the plane!

MIA
SFO
Excellent 8.6

No personal TV for entertainment

ORD
RDU
Good 7.0

Landed on time. AA is mostly on or before schedule. Definitely like that part. Smooth flying as well.

No interactions with the crew this time. Boarding is okay.

Mon, Jan 29
ISP
LHR
19h 30m
Tue, Feb 6
LHR
ISP
14h 52m
Trip: 9 days
7.2GoodShow reviews
Overall 7.2 Good
Based on 25860 reviews
Overall
7.3
Boarding
7.5
Comfort
7.1
Crew
7.8
Entertainment
6.7
Food
6.6
IND
CLT
Good 6.8

I did like that "new plane" smell. Good pretzels.

Plane was too new; computer system hadn't been set right. Left 45 minutes late, though made up some lost time in the air. Very rude passengers (obviously not the airline's fault, I know). Everyone thinks they should be the first to get off the plane!

MLB
CLT
Okay 5.6

pleasant crew

CRJ900 is a small plane. no WiFi

DCA
TPA
Excellent 8.6

The cabin crew was great at boarding and organizing the overhead bin space. Also, ground staff didn’t start check roll aboards before the overheads bins were full. There is nothing more frustrating than getting on after forced to gate check your bag to empty bin space (ahem, United at SFO).

Couldn’t get the entertainment to work.

EWR
CLT
Good 7.0

Smooth flying and lots of respects to the pilots for their dedicated work. The entertainment really works very well.

Poor Service. The service of drinks is done very poorly. Really concerned with the attitude. Never need those complimentary drinks.

ORD
RDU
Good 7.0

Landed on time. AA is mostly on or before schedule. Definitely like that part. Smooth flying as well.

No interactions with the crew this time. Boarding is okay.

*
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The fares displayed include all taxes and fees for economy class travel and were found by the provider in the last 72 hours. Seats are limited and may not be available on all flights and days. Fares are subject to change and may not be available on all flights or dates of travel. Some carriers charge additional fees for extra checked bags. Please check the carriers' sites.