Cheap flights from London Heathrow Airport to San Juan from £314

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 16/4. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — SJU
23 Jan — 30 Jan1
1 adult
1 adult, Economy, 0 bags

Cheapflights Tip: The best prices from London Heathrow to San Juan are usually found in September or March, booked 43 days in advance, depart on a Monday or Wednesday and return on a Tuesday

Cheap flight deals from Heathrow to San Juan

Enter your travel dates to find the best prices.

Cheapest flights from Heathrow to San Juan
Explore the most affordable flight options available from Heathrow to San Juan. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 24 December 2025.

Mon 29/1209:20LHR - SJU
1 stop14h 05mJetBlue
Tue 13/114:00SJU - LHR
1 stop12h 55mJetBlue
Deal found 22/12£532
Mon 29/1209:20LHR - SJU
1 stop14h 05mJetBlue
Wed 14/114:00SJU - LHR
1 stop12h 55mJetBlue
Deal found 22/12£551
Mon 29/1209:20LHR - SJU
1 stop14h 05mJetBlue
Sat 17/113:24SJU - LHR
1 stop16h 06mJetBlue
Deal found 22/12£554
Sun 28/1207:45LHR - SJU
1 stop18h 49mJetBlue
Thu 15/114:20SJU - LHR
1 stop15h 10mJetBlue
Deal found 22/12£580
Wed 31/1209:20LHR - SJU
1 stop13h 15mJetBlue
Wed 14/114:20SJU - LHR
1 stop15h 10mJetBlue
Deal found 22/12£588
Sat 27/1209:20LHR - SJU
1 stop14h 05mJetBlue
Fri 16/114:00SJU - LHR
1 stop12h 55mJetBlue
Deal found 22/12£602
Tue 30/1209:20LHR - SJU
1 stop14h 05mJetBlue
Wed 14/114:00SJU - LHR
1 stop12h 55mJetBlue
Deal found 22/12£606
Tue 30/1209:20LHR - SJU
1 stop14h 05mJetBlue
Fri 16/114:00SJU - LHR
1 stop12h 55mJetBlue
Deal found 22/12£610
Wed 31/1212:50LHR - SJU
1 stop15h 46mUnited Airlines
Sat 17/117:50SJU - LHR
1 stop13h 00mUnited Airlines
Deal found 22/12£613
Wed 31/1209:20LHR - SJU
1 stop13h 15mJetBlue
Fri 16/114:20SJU - LHR
1 stop15h 10mJetBlue
Deal found 22/12£628
Tue 30/1209:20LHR - SJU
1 stop14h 05mJetBlue
Thu 15/114:00SJU - LHR
1 stop12h 55mJetBlue
Deal found 22/12£643
Wed 24/1212:20LHR - SJU
1 stop17h 39mJetBlue
Mon 29/1212:40SJU - LHR
1 stop14h 15mJetBlue
Deal found 23/12£654

Find flight deals from Heathrow to San Juan

Discover tips and strategies to find the most affordable flight options for your journey from Heathrow (LHR) to San Juan (PR1). 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 24 December 2025.

Round-trip from

£506

One-way from

£314

Popular in

December

Cheapest in

September

Average price

£971
JetBlue
  • JetBlue
  • 2/3-5/3
  • 2 total stops
  • 29h 06m total
  • London to San Juan
16/4
  • 16/4
  • 2 total stops
  • 27h 05m total
  • London to San Juan
Highest demand for flights based on searches. 8% potential increase in price (£46 potential increase over avg. return price).
Cheapest flight prices on average. 4% potential price decrease (£23 potential savings vs. average return price).
Average for round-trip flights in December 2025

Cheapflights Fare Finder

 
Customise your flight search to find flights from Heathrow to San Juan 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 858,174 searches. Data last updated 24 December 2025.
Use the filters below to find and compare flights from London Heathrow Airport to San Juan that are best for you.

Fly from

Heathrow

Fly to

San Juan

Route

Depart

Return

Price

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Fri 6/2

12:20-02:33

1 stop18h 13m

San Juan Luis Munoz Marin Intl

Fri 13/2

23:50-22:00

1 stop18h 10m

£527

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Sun 1/3

09:20-10:02

1 stop28h 42m

San Juan Luis Munoz Marin Intl

Sun 8/3

05:55-20:45

1 stop34h 50m

£530

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Wed 4/2

15:45-17:05

3 stops29h 20m

San Juan Luis Munoz Marin Intl

Wed 11/2

10:52-20:35

2 stops29h 43m

£610

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Thu 5/2

13:00-15:26

2 stops30h 26m

San Juan Luis Munoz Marin Intl

Thu 12/2

16:25-06:30

2 stops34h 05m

£637

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Mon 26/1

13:40-13:20

2 stops27h 40m

San Juan Luis Munoz Marin Intl

Thu 5/2

11:06-17:30

2 stops26h 24m

£646

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Sat 10/1

08:05-23:50

1 stop19h 45m

San Juan Luis Munoz Marin Intl

Sat 17/1

10:25-09:30

1 stop19h 05m

£652

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Sun 1/3

08:15-03:50

2 stops23h 35m

San Juan Luis Munoz Marin Intl

Sun 8/3

14:40-21:35

2 stops26h 55m

£661

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Sat 31/1

13:40-13:20

2 stops27h 40m

San Juan Luis Munoz Marin Intl

Wed 11/2

16:40-18:55

2 stops22h 15m

£691

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Mon 13/4

06:00-22:01

2 stops21h 01m

San Juan Luis Munoz Marin Intl

Sat 18/4

01:59-20:45

1 stop13h 46m

£695

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Wed 28/1

12:15-02:25

2 stops18h 10m

San Juan Luis Munoz Marin Intl

Thu 5/2

11:06-10:50

2 stops19h 44m

£710

Flights are sorted by cheapest return flights first.

Deals found on 23/12

Showing 1-10 of 21 results
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Best time to book a flight from Heathrow to San Juan

Have a flexible travel schedule? Discover the best time to fly to San Juan from Heathrow with our price prediction graph.
Estimated return 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 Heathrow Airport to San Juan

How far ahead should I book a flight from London Heathrow Airport to San Juan?

Use this chart to determine the optimal time to book a return flight from Heathrow to San Juan. Price data was last updated on 19 December 2025.

The best time to book flights from London Heathrow Airport to San Juan is 43 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.

What is the cheapest month to book a flight from London Heathrow Airport to San Juan?

Currently, June is the cheapest month in which you can book a flight from London Heathrow Airport to San Juan (average of £436). Flying from London Heathrow Airport to San Juan in December is currently the most expensive (average of £539). 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 LHR to SJU?

Find hourly flight availability from Heathrow to San Juan. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 24 December 2025.

A simple way to save on the total cost of your ticket is to fly from London Heathrow Airport to San Juan in the afternoon. If you’re flexible enough to do this you can expect to save up to 12% on your trip compared to booking a flight in the morning.

How much does it cost for a return flight from London Heathrow Airport to San Juan?

Reviews of airlines servicing San Juan

Get insights into the airlines that provide service to San Juan. 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 San Juan. Reviews last updated 24 December 2025.
Read reviews from past customers who have flown with Finnair, JetBlue, andIcelandair from London Heathrow Airport to San Juan. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.

Food

6.7

Boarding

7.6

Overall

7.6

Crew

8.1

Entertainment

6.9

Comfort

7.4

Reviews

1 / 20
4.0
Okay

Anonymous,Sept 2025

WAW - HEL

My flight to Europe was cancelled and rebooked. Bags got lost by FinnAir. Flight back home from Europe was cancelled the very next day after we landed. Zero compensation for these back to back cancellations on the exact same trip. Kayak doesn’t help with flight cancellation before trips says to contact trip protection only for trip protection to say it’s up to kayak. Don’t fly FinnAir.

Food

6.7

Boarding

7.6

Overall

7.6

Crew

8.1

Entertainment

6.9

Comfort

7.4

Reviews

1 / 20
4.0
Okay

Anonymous,Sept 2025

WAW - HEL

My flight to Europe was cancelled and rebooked. Bags got lost by FinnAir. Flight back home from Europe was cancelled the very next day after we landed. Zero compensation for these back to back cancellations on the exact same trip. Kayak doesn’t help with flight cancellation before trips says to contact trip protection only for trip protection to say it’s up to kayak. Don’t fly FinnAir.

Food

6.7

Boarding

7.6

Overall

7.6

Crew

8.1

Entertainment

6.9

Comfort

7.4

Reviews

1 / 20
4.0
Okay

Anonymous,Sept 2025

WAW - HEL

My flight to Europe was cancelled and rebooked. Bags got lost by FinnAir. Flight back home from Europe was cancelled the very next day after we landed. Zero compensation for these back to back cancellations on the exact same trip. Kayak doesn’t help with flight cancellation before trips says to contact trip protection only for trip protection to say it’s up to kayak. Don’t fly FinnAir.

Food

6.7

Boarding

7.6

Overall

7.6

Crew

8.1

Entertainment

6.9

Comfort

7.4

Reviews

1 / 20
4.0
Okay

Anonymous,Sept 2025

WAW - HEL

My flight to Europe was cancelled and rebooked. Bags got lost by FinnAir. Flight back home from Europe was cancelled the very next day after we landed. Zero compensation for these back to back cancellations on the exact same trip. Kayak doesn’t help with flight cancellation before trips says to contact trip protection only for trip protection to say it’s up to kayak. Don’t fly FinnAir.

Food

6.7

Boarding

7.6

Overall

7.6

Crew

8.1

Entertainment

6.9

Comfort

7.4

Reviews

1 / 20
4.0
Okay

Anonymous,Sept 2025

WAW - HEL

My flight to Europe was cancelled and rebooked. Bags got lost by FinnAir. Flight back home from Europe was cancelled the very next day after we landed. Zero compensation for these back to back cancellations on the exact same trip. Kayak doesn’t help with flight cancellation before trips says to contact trip protection only for trip protection to say it’s up to kayak. Don’t fly FinnAir.

Food

6.7

Boarding

7.6

Overall

7.6

Crew

8.1

Entertainment

6.9

Comfort

7.4

Reviews

1 / 20
4.0
Okay

Anonymous,Sept 2025

WAW - HEL

My flight to Europe was cancelled and rebooked. Bags got lost by FinnAir. Flight back home from Europe was cancelled the very next day after we landed. Zero compensation for these back to back cancellations on the exact same trip. Kayak doesn’t help with flight cancellation before trips says to contact trip protection only for trip protection to say it’s up to kayak. Don’t fly FinnAir.

Related info for your journey

Find useful and relevant information for your journey from Heathrow to San Juan. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
  • How long is the flight from London Heathrow Airport to San Juan?

    Airlines like JetBlue and TAP AIR PORTUGAL fly from London Heathrow Airport to San Juan in about 18h 13m. The time it takes to get you to your destination can typically vary by up to 9h 27m. The distance from London Heathrow Airport to San Juan is about 4179 mi. When browsing for deals, the options you’ll see will be for both direct flights and flights with stops.

  • What are the cheapest airlines flying from London Heathrow Airport to San Juan round-trip?

    Our cheapest airline available from London Heathrow Airport to San Juan is Virgin Atlantic. Our recent data shows that you can find tickets from as low as £342 on this airline. Additional options worth looking into are Finnair and JetBlue, starting at £447 and £451 round-trip. Virgin Atlantic is currently priced 46% below the average price you’ll pay for this route.

  • Can I find deals for flights from Heathrow to San Juan that include hotel bookings?

    Yes. In addition to deals on Heathrow to San Juan flights, Cheapflights offers holiday packages that include both flights and hotel.

  • How can I find direct flights from Heathrow to San Juan?

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

  • Can I find deals for business class flights from Heathrow to San Juan?

    Yes. Cheapflights offers flight deals from Heathrow to San Juan 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 Heathrow Airport to San Juan?

    Currently, June is the cheapest month in which you can book a flight from London Heathrow Airport to San Juan (average of £436). Flying from London Heathrow Airport to San Juan in December is currently the most expensive (average of £539). 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.

See more FAQs

Browse thousands of different options on Cheapflights for your next trip

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Top 6 airlines flying from Heathrow to San Juan

Discover the top 6 airlines that operate flights from Heathrow to San Juan. 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 858,174 searches. Data last updated 24 December 2025.
AirlineCheapestAverageFlexibilityOn-time
Virgin AtlanticCheapest£342Average£1,032FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
FinnairCheapest£447Average£539FlexibilityNo cancel feeOn-time76%
Search Finnair flights
JetBlueCheapest£454Average£606FlexibilityNo cancel feeOn-time62%
Search JetBlue flights
IcelandairCheapest£482Average£647FlexibilityNo cancel feeOn-time76%
Search Icelandair flights
IberiaCheapest£499Average£815FlexibilityNo cancel feeOn-time77%
Search Iberia flights
British AirwaysCheapest£536Average£947FlexibilityNo cancel feeOn-time70%
Search British Airways flights

Fly with Cheapflights

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How does Cheapflights help users find flights from Heathrow to San Juan?

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Why should you use Cheapflights to find cheap flight tickets from Heathrow to San Juan?

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Can Cheapflights find flights from Heathrow to San Juan with no change fees?

Users can book flights with no change fees policies with our dedicated filters. Book flights from Heathrow to San Juan flexibly with Cheapflights today.

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