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$458+ Cheap flights from London (LON) to Philadelphia (PHL)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 9/1. Fares are subject to change and may not be available on all flights or dates of travel.
LON — PHL
Jul 13 — Jul 201
Mon 7/13
Mon 7/20
1 adult, Economy
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1. Tell us where you want to go

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Cheapflights Tip: The best prices from London to Philadelphia are usually found in September or January, booked 58 days in advance, depart on a Monday or Wednesday and return on a Wednesday

Cheap flight deals from London to Philadelphia

Cheapest flights from London to Philadelphia
Explore the most affordable flight options available from London to Philadelphia. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 13, 2026.

This SWISS deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure SWISS is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/317:15 pm
LCY
-
PHL
2 stops25h 50m
SWISS
Sun 9/205:40 pm
PHL
-
LCY
2 stops18h 45m
SWISS
Deal found 6/10$843
This Kiwi.com deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 6/142:00 pm
LGW
-
PHL
1 stop15h 44m
Multiple Airlines
Sat 7/259:16 pm
PHL
-
LGW
1 stop31h 44m
Multiple Airlines
Deal found 6/10$843
This Kiwi.com deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/812:00 pm
STN
-
PHL
1 stop11h 55m
Multiple Airlines
Mon 10/128:25 pm
PHL
-
STN
1 stop11h 25m
Multiple Airlines
Deal found 6/9$844
This Justfly.com deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/109:15 am
LCY
-
PHL
1 stop11h 50m
Multiple Airlines
Mon 7/205:40 pm
PHL
-
LCY
2 stops13h 55m
Multiple Airlines
Deal found 6/10$844
This Air Canada deal was found by Cheapflights users on 6/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/262:10 pm
LHR
-
PHL
2 stops14h 34m
Multiple Airlines
Mon 6/2910:05 am
PHL
-
LHR
2 stops15h 30m
Multiple Airlines
Deal found 6/13$844
This Kiwi.com deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/92:00 pm
LGW
-
PHL
1 stop15h 51m
Multiple Airlines
Mon 7/134:40 pm
PHL
-
LGW
2 stops36h 20m
Multiple Airlines
Deal found 6/9$844
This The Travel House deal was found by Cheapflights users on 6/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure The Travel House is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/109:30 am
LHR
-
PHL
1 stop11h 35m
Lufthansa
Thu 7/165:40 pm
PHL
-
LHR
2 stops22h 05m
Lufthansa
Deal found 6/12$845
This Expedia deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/1712:05 pm
LGW
-
PHL
2 stops26h 45m
TAP AIR PORTUGAL
Sun 11/16:00 am
PHL
-
LGW
2 stops22h 50m
TAP AIR PORTUGAL
Deal found 6/11$845
This United Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/124:20 pm
LHR
-
PHL
1 stop22h 04m
United Airlines
Sun 1/178:00 pm
PHL
-
LHR
1 stop29h 40m
United Airlines
Deal found 6/9$846
This Kiwi.com deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/82:00 pm
LGW
-
PHL
1 stop14h 44m
Multiple Airlines
Fri 7/174:40 pm
PHL
-
LGW
2 stops36h 20m
Multiple Airlines
Deal found 6/11$846
This ChecknFly deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure ChecknFly is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/189:15 am
LHR
-
PHL
Nonstop7h 55m
Iberia
Wed 6/247:20 pm
PHL
-
LHR
Nonstop7h 30m
Iberia
Deal found 6/9$847
This Gotogate deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/109:15 am
LCY
-
PHL
1 stop11h 50m
Multiple Airlines
Sun 7/265:40 pm
PHL
-
LCY
2 stops13h 55m
Multiple Airlines
Deal found 6/11$848

Find flight deals from London to Philadelphia

Discover tips and strategies to find the most affordable flight options for your journey from London (LON) to Philadelphia (PHL). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated June 13, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$843
(SWISS)

One-way from

$458
(Expedia)

Popular in

July

Cheapest in

September

Average price

$935

Good round-trip deal

$935 or less

Good one-way deal

$760 or less
Provider with most accurate pricing for London (LON)-Philadelphia flight deals.
Search Deals
Provider most trusted by Cheapflights users for London (LON)-Philadelphia flights.
Search Deals
From London (LON) to Philadelphia
Search Deals
One-way flight from London (LON) to Philadelphia
Search Deals
Highest demand for flights based on searches. 9% potential increase in price ($87 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($11 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in June 2026
Search Deals
Price to beat on a round-trip flight from London (LON) to Philadelphia.
Search Deals
Price to beat on a one-way flight from London (LON) to Philadelphia.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from London to Philadelphia 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, Cheapflights users made 2,558,603 searches. Data last updated June 13, 2026.
Use the filters below to find and compare flights from London to Philadelphia that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

LondonPhiladelphia

LCY - PHL

LCYPHL

London City

Tue 7/7

7:15 pm-4:05 pm

2 stops25h 50m

Philadelphia

Tue 7/14

5:40 pm-12:35 pm

2 stops13h 55m

$866

LondonPhiladelphia

LHR - PHL

LHRPHL

London Heathrow

Sun 7/12

3:30 pm-4:05 pm

1 stop29h 35m

Philadelphia

Sat 7/25

6:00 am-6:45 am

1 stop19h 45m

$872

LondonPhiladelphia

LCY - PHL

LCYPHL

London City

Wed 11/25

8:40 am-3:35 pm

1 stop11h 55m

Philadelphia

Sun 11/29

9:10 pm-4:25 pm

1 stop14h 15m

$874

LondonPhiladelphia

STN - PHL

STNPHL

London Stansted

Tue 9/1

7:05 am-6:55 pm

2 stops16h 50m

Philadelphia

Mon 9/7

8:25 pm-12:50 pm

1 stop11h 25m

$876

LondonPhiladelphia

LCY - PHL

LCYPHL

London City

Fri 10/9

9:15 am-5:54 pm

2 stops37h 39m

Philadelphia

Thu 10/15

5:40 pm-12:35 pm

2 stops13h 55m

$876

LondonPhiladelphia

LCY - PHL

LCYPHL

London City

Fri 10/9

9:15 am-5:54 pm

2 stops37h 39m

Philadelphia

Wed 10/14

5:40 pm-12:35 pm

2 stops13h 55m

$877

LondonPhiladelphia

LHR - PHL

LHRPHL

London Heathrow

Sun 7/12

7:30 am-4:05 pm

1 stop13h 35m

Philadelphia

Sat 7/18

6:10 am-5:55 am

2 stops18h 45m

$890

LondonPhiladelphia

LTN - PHL

LTNPHL

London Luton

Mon 8/10

8:15 am-6:55 pm

1 stop15h 40m

Philadelphia

Fri 8/14

8:25 pm-5:25 pm

1 stop16h 00m

$894

LondonPhiladelphia

LCY - PHL

LCYPHL

London City

Tue 9/1

7:15 pm-4:05 pm

2 stops25h 50m

Philadelphia

Tue 9/8

11:03 am-8:40 am

2 stops16h 37m

$900

LondonPhiladelphia

LHR - PHL

LHRPHL

London Heathrow

Wed 7/1

10:05 am-9:03 pm

1 stop15h 58m

Philadelphia

Sat 7/4

6:46 pm-8:00 am

1 stop32h 14m

$902

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/12

Showing 1-10 of 60 resultsSorted by cheapest first
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Compare providers for flights from London to Philadelphia

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from London to Philadelphia in June.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
Justfly.comPrice Accuracy3 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on London-Philadelphia flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on London-Philadelphia flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from London-Philadelphia flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on London-Philadelphia flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for London-Philadelphia flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from London to Philadelphia

Have a flexible travel schedule? Discover the best time to fly to Philadelphia from London 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 London to Philadelphia

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

Currently, August is the cheapest month in which you can book a flight from London to Philadelphia (average of $338). Flying from London to Philadelphia in June is currently the most expensive (average of $1,670). 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.

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

Find hourly flight availability from London to Philadelphia. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated June 13, 2026.

When flying from London to Philadelphia, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

Weekly flight availability from London to Philadelphia

Explore weekly flight availability from London to Philadelphia. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated June 13, 2026.

The most flights from LON to PHL are scheduled on a Monday (15 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (15 on average).

How much does it cost to fly round-trip from London to Philadelphia?

How often are flights from London to Philadelphia delayed?

About 18% of weekly flights between London and Philadelphia have experienced delays in the past year, with the average delay time being 174 minutes.

What is the most punctual flight time for London to Philadelphia flights?

Historically, flights departing in the morning are less likely to be delayed, whereas flights leaving in the early afternoon tend to experience delays more often.

What day of the week experiences the fewest flight delays on this route?

Saturday tends to have the lowest number of delays on this route, whereas Thursday has historically faced a higher average of delays compared to other days of the week.

Which airline has the best punctuality record on London to Philadelphia flights?

Over the last year, American Airlines have had the lowest number of delays on this route, with just 18% of flights being delayed.

How far ahead should I book a flight from London to Philadelphia?

The best time to book flights from London to Philadelphia is 11 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

The best insider tips for London to Philadelphia flights

AI-powered summary based on content written by travel experts. AI can make mistakes.
Cheapflights partnered with top experts to bring you the best recommendations for your London to Philadelphia trip
Our travel experts
Mark Chesnut

Mark Chesnut

Expert on PHL

Mark Chesnut is a travel writer and public speaker with more than 30 years of experience. The 2019 winner of the NLGJA Excellence in Travel Writing Award, Mark is the author of the book “Prepare for Departure” and has covered air travel for multiple top consumer and trade media outlets.

Read more
Ramsey Qubein

Ramsey Qubein

Expert on LHR

An avid traveler and aviation expert who has visited 173 countries, all 50 states and seven continents, Ramsey Qubein flies nearly 400,000 miles a year. As a North Carolina-based freelance journalist for publications including Conde Nast Traveler, Forbes, USA Today and Bloomberg among others, he explores the latest trends in aviation, hospitality, cruises and business.

Read more

Reviews of airlines servicing Philadelphia

Get insights into the airlines that provide service to Philadelphia. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Philadelphia. Reviews last updated June 13, 2026.
Get a feel of what it's like to fly with Aer Lingus,American Airlines, andIberia from London to Philadelphia by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Aer Lingus
7.3
Good
1,603 reviews

Crew

8.1

Comfort

7.2

Food

6.7

Entertainment

7.0

Overall

7.3

Boarding

7.4

Reviews

1 / 20
2.0
Mediocre

Anonymous,May 2026

DUB - EWR

Underpricer is a terrible organization that inserted itself as a “travel agent” simply by way of me booking on kayak. Never would I have willing assented to using underpricer. Further, we had a problem whereby two duplicate one-way flights from Dublin were inadvertently booked for me and my wife, stemming from a family emergency. My wife’s sister / my sister in law had a brain tumor and immediate surgery to remove it, which obviously impacted our previously planned travel arrangements. I tried to cancel the flight due to the extenuating circumstances. Underpricer said canceling was not possible, but a credit would be possible for the exact same flight - one way from Dublin - to be used in one year from the original flight date. I asked if it would be possible to make the credit a general credit to any participating AerLingus airport destination, which would allow more flexibility than having to go back to Ireland within a year. In order to pursue the credit, Underpricer requested documentary proof regarding my sister in laws brain tumor, which we gave them. Underpricer then asked us to document our relationship to the patient - so I gave them my marriage certificate to evidence my wife and her sister having the same last name. Underpricer asked for further proof, so we gave them copies of my passport, my wife’s passport, and my sister in laws passport. All of these hoops to jump through for Underpricer, with sporadic communication on their part throughout, only for them to say 3 days before the original booking that no credit was available - not even the one they originally offered. They said my only option was to pick a date within the next year to move the flight to - and of course to make that change, they charged me an additional $350 fee just to make that change. What a pathetic, fraudulent organization. Kayak should be embarrassed to be associated with Underpricer and should cease that relationship immediately. And for AerLingus, who only Underpricer could talk to regarding the booking (I was not permitted) to not understand our family’s situation and just stand by blanket policy that no credit is permitted, is equally disappointing.
Aer Lingus
7.3
Good
1,603 reviews
Aer Lingus
7.3
Good
1,603 reviews

Crew

8.1

Comfort

7.2

Food

6.7

Entertainment

7.0

Overall

7.3

Boarding

7.4

Reviews

1 / 20
2.0
Mediocre

Anonymous,May 2026

DUB - EWR

Underpricer is a terrible organization that inserted itself as a “travel agent” simply by way of me booking on kayak. Never would I have willing assented to using underpricer. Further, we had a problem whereby two duplicate one-way flights from Dublin were inadvertently booked for me and my wife, stemming from a family emergency. My wife’s sister / my sister in law had a brain tumor and immediate surgery to remove it, which obviously impacted our previously planned travel arrangements. I tried to cancel the flight due to the extenuating circumstances. Underpricer said canceling was not possible, but a credit would be possible for the exact same flight - one way from Dublin - to be used in one year from the original flight date. I asked if it would be possible to make the credit a general credit to any participating AerLingus airport destination, which would allow more flexibility than having to go back to Ireland within a year. In order to pursue the credit, Underpricer requested documentary proof regarding my sister in laws brain tumor, which we gave them. Underpricer then asked us to document our relationship to the patient - so I gave them my marriage certificate to evidence my wife and her sister having the same last name. Underpricer asked for further proof, so we gave them copies of my passport, my wife’s passport, and my sister in laws passport. All of these hoops to jump through for Underpricer, with sporadic communication on their part throughout, only for them to say 3 days before the original booking that no credit was available - not even the one they originally offered. They said my only option was to pick a date within the next year to move the flight to - and of course to make that change, they charged me an additional $350 fee just to make that change. What a pathetic, fraudulent organization. Kayak should be embarrassed to be associated with Underpricer and should cease that relationship immediately. And for AerLingus, who only Underpricer could talk to regarding the booking (I was not permitted) to not understand our family’s situation and just stand by blanket policy that no credit is permitted, is equally disappointing.
American Airlines
7.1
Good
11,648 reviews
Aer Lingus
7.3
Good
1,603 reviews

Crew

8.1

Comfort

7.2

Food

6.7

Entertainment

7.0

Overall

7.3

Boarding

7.4

Reviews

1 / 20
2.0
Mediocre

Anonymous,May 2026

DUB - EWR

Underpricer is a terrible organization that inserted itself as a “travel agent” simply by way of me booking on kayak. Never would I have willing assented to using underpricer. Further, we had a problem whereby two duplicate one-way flights from Dublin were inadvertently booked for me and my wife, stemming from a family emergency. My wife’s sister / my sister in law had a brain tumor and immediate surgery to remove it, which obviously impacted our previously planned travel arrangements. I tried to cancel the flight due to the extenuating circumstances. Underpricer said canceling was not possible, but a credit would be possible for the exact same flight - one way from Dublin - to be used in one year from the original flight date. I asked if it would be possible to make the credit a general credit to any participating AerLingus airport destination, which would allow more flexibility than having to go back to Ireland within a year. In order to pursue the credit, Underpricer requested documentary proof regarding my sister in laws brain tumor, which we gave them. Underpricer then asked us to document our relationship to the patient - so I gave them my marriage certificate to evidence my wife and her sister having the same last name. Underpricer asked for further proof, so we gave them copies of my passport, my wife’s passport, and my sister in laws passport. All of these hoops to jump through for Underpricer, with sporadic communication on their part throughout, only for them to say 3 days before the original booking that no credit was available - not even the one they originally offered. They said my only option was to pick a date within the next year to move the flight to - and of course to make that change, they charged me an additional $350 fee just to make that change. What a pathetic, fraudulent organization. Kayak should be embarrassed to be associated with Underpricer and should cease that relationship immediately. And for AerLingus, who only Underpricer could talk to regarding the booking (I was not permitted) to not understand our family’s situation and just stand by blanket policy that no credit is permitted, is equally disappointing.
Iberia
7.0
Good
3,233 reviews
Aer Lingus
7.3
Good
1,603 reviews

Crew

8.1

Comfort

7.2

Food

6.7

Entertainment

7.0

Overall

7.3

Boarding

7.4

Reviews

1 / 20
2.0
Mediocre

Anonymous,May 2026

DUB - EWR

Underpricer is a terrible organization that inserted itself as a “travel agent” simply by way of me booking on kayak. Never would I have willing assented to using underpricer. Further, we had a problem whereby two duplicate one-way flights from Dublin were inadvertently booked for me and my wife, stemming from a family emergency. My wife’s sister / my sister in law had a brain tumor and immediate surgery to remove it, which obviously impacted our previously planned travel arrangements. I tried to cancel the flight due to the extenuating circumstances. Underpricer said canceling was not possible, but a credit would be possible for the exact same flight - one way from Dublin - to be used in one year from the original flight date. I asked if it would be possible to make the credit a general credit to any participating AerLingus airport destination, which would allow more flexibility than having to go back to Ireland within a year. In order to pursue the credit, Underpricer requested documentary proof regarding my sister in laws brain tumor, which we gave them. Underpricer then asked us to document our relationship to the patient - so I gave them my marriage certificate to evidence my wife and her sister having the same last name. Underpricer asked for further proof, so we gave them copies of my passport, my wife’s passport, and my sister in laws passport. All of these hoops to jump through for Underpricer, with sporadic communication on their part throughout, only for them to say 3 days before the original booking that no credit was available - not even the one they originally offered. They said my only option was to pick a date within the next year to move the flight to - and of course to make that change, they charged me an additional $350 fee just to make that change. What a pathetic, fraudulent organization. Kayak should be embarrassed to be associated with Underpricer and should cease that relationship immediately. And for AerLingus, who only Underpricer could talk to regarding the booking (I was not permitted) to not understand our family’s situation and just stand by blanket policy that no credit is permitted, is equally disappointing.
British Airways
6.7
Okay
8,047 reviews
Aer Lingus
7.3
Good
1,603 reviews

Crew

8.1

Comfort

7.2

Food

6.7

Entertainment

7.0

Overall

7.3

Boarding

7.4

Reviews

1 / 20
2.0
Mediocre

Anonymous,May 2026

DUB - EWR

Underpricer is a terrible organization that inserted itself as a “travel agent” simply by way of me booking on kayak. Never would I have willing assented to using underpricer. Further, we had a problem whereby two duplicate one-way flights from Dublin were inadvertently booked for me and my wife, stemming from a family emergency. My wife’s sister / my sister in law had a brain tumor and immediate surgery to remove it, which obviously impacted our previously planned travel arrangements. I tried to cancel the flight due to the extenuating circumstances. Underpricer said canceling was not possible, but a credit would be possible for the exact same flight - one way from Dublin - to be used in one year from the original flight date. I asked if it would be possible to make the credit a general credit to any participating AerLingus airport destination, which would allow more flexibility than having to go back to Ireland within a year. In order to pursue the credit, Underpricer requested documentary proof regarding my sister in laws brain tumor, which we gave them. Underpricer then asked us to document our relationship to the patient - so I gave them my marriage certificate to evidence my wife and her sister having the same last name. Underpricer asked for further proof, so we gave them copies of my passport, my wife’s passport, and my sister in laws passport. All of these hoops to jump through for Underpricer, with sporadic communication on their part throughout, only for them to say 3 days before the original booking that no credit was available - not even the one they originally offered. They said my only option was to pick a date within the next year to move the flight to - and of course to make that change, they charged me an additional $350 fee just to make that change. What a pathetic, fraudulent organization. Kayak should be embarrassed to be associated with Underpricer and should cease that relationship immediately. And for AerLingus, who only Underpricer could talk to regarding the booking (I was not permitted) to not understand our family’s situation and just stand by blanket policy that no credit is permitted, is equally disappointing.

Related info for your journey

Find useful and relevant information for your journey from London to Philadelphia. 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 into for flights to Philadelphia from London?

    Located just 7.0 mi from the city center, Philadelphia is the airport most travelers will use when flying to Philadelphia from London. Booking flights from London to Philadelphia (PHL) should be relatively easy as there are 15 daily inbound flights from London from 3 different airlines.

  • How long is the flight from London to Philadelphia?

    SWISS, United Airlines, and British Airways can get you from London to Philadelphia in just under 11h 55m. Your travel time can differ by up to 17h 40m. There are 3553 mi between London and Philadelphia. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

  • What are the cheapest airlines flying from London to Philadelphia round-trip?

    According to our current data, American Airlines ($610), British Airways ($614), and Aer Lingus ($670) offers the cheapest pricing from London to Philadelphia. You may be able to fly from London to Philadelphia for 26% less than the average price by searching for these airlines.

  • What are the cheapest airlines to fly from London to Philadelphia one-way?

    The cheapest airlines for a one-way flight from London to Philadelphia are JetBlue ($452), Aer Lingus ($479), and American Airlines ($490).

  • What are the most popular routes from London to Philadelphia?

    When deciding which route to take from London to Philadelphia consider London Heathrow - Philadelphia, London Gatwick - Philadelphia or London City - Philadelphia as they are the most popular.

  • What are the most reliable airlines from London to Philadelphia?

    Looking for the most reliable airlines to get you to your destination on time? Our data shows these are most likely to get you from London to Philadelphia on time: Malaysia Airlines (87%), American Airlines (83%), Finnair (83%).

  • What are the cheapest flights from London to Philadelphia?

    While on average a flight from London to Philadelphia is generally $1,461, our data shows the cheapest flight currently is $592. When looking at the most popular route, (London Heathrow - Philadelphia), you can expect to pay $635 for that flight.

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

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

  • How can I find direct flights from London to Philadelphia?

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

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

    Yes. Cheapflights offers flight deals from London to Philadelphia 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 London to Philadelphia?

    Currently, August is the cheapest month in which you can book a flight from London to Philadelphia (average of $338). Flying from London to Philadelphia in June is currently the most expensive (average of $1,670). 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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Traveling to a place near Philadelphia?

Book flights to Philadelphia if you plan to visit one of these locations
Wildwood
Reading
King of Prussia
Camden
Ocean City
Plymouth Meeting
Cherry Hill
Lewes
Dewey Beach
Pottstown
Ephrata
Milford
Wildwood Crest
Dover
Elkton
Essington
Willow Grove
New Castle
Millville
Vineland

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Top 3 airlines flying from London to Philadelphia

Discover the top 3 airlines that operate flights from London to Philadelphia. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated June 13, 2026.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$610Average$814FlexibilityNo cancel feeOn-time71%
British AirwaysCheapest$614Average$781FlexibilityNo cancel feeOn-time70%
Aer LingusCheapest$670Average$994FlexibilityNo cancel feeOn-timeN/A

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