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Cheap flights from London Heathrow Airport to San Juan from £325

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 10/6. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — SJU
21 Apr — 28 Apr1
1 adult

Cheapflights Tip: The best prices from London Heathrow to San Juan are usually found in September or February, booked 76 days in advance, depart on a Monday or Wednesday and return on a Tuesday

Cheap 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 16 April 2025.

Round-trip from

£483

One-way from

£325

Popular in

July

Cheapest in

September

Average price

£614
Icelandair
  • Icelandair
  • 22/9-28/9
  • 2 total stops
  • 30h 33m total
  • London to San Juan
10/6
  • 10/6
  • 2 total stops
  • 47h 27m total
  • London to San Juan
Highest demand for flights based on searches. 17% potential increase in price (£101 potential increase over avg. return price).
Cheapest flight prices on average. 3% potential price decrease (£15 potential savings vs. average return price).
Average for round-trip flights in April 2025

Find flight deals from Heathrow to San Juan

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 16 April 2025.

Mon 22/908:15LHR - SJU
1 stop18h 03mIcelandair
Sun 28/903:15SJU - LHR
1 stop12h 30mIcelandair
Deal found 15/4£483
Tue 23/908:15LHR - SJU
1 stop18h 03mJetBlue
Mon 29/903:15SJU - LHR
1 stop12h 30mJetBlue
Deal found 15/4£508
Thu 15/509:15LHR - SJU
1 stop14h 35mIberia
Thu 22/513:30SJU - LHR
1 stop14h 55mIberia
Deal found 15/4£534
Fri 30/516:50LHR - SJU
1 stop27h 39mMultiple Airlines
Fri 6/621:30SJU - LHR
1 stop28h 45mMultiple Airlines
Deal found 15/4£583
Thu 6/1112:25LHR - SJU
2 stops19h 55mTAP AIR PORTUGAL
Sat 15/1106:15SJU - LHR
2 stops25h 10mTAP AIR PORTUGAL
Deal found 15/4£678
Mon 28/414:10LHR - SJU
2 stops30h 30mUnited Airlines
Thu 22/501:05SJU - LHR
1 stop14h 35mUnited Airlines
Deal found 15/4£688
Fri 19/907:30LHR - SJU
2 stops21h 27mLufthansa
Sun 28/913:30SJU - LHR
1 stop12h 45mLufthansa
Deal found 15/4£826
Wed 24/911:30LHR - SJU
1 stop12h 00mAmerican Airlines
Tue 30/911:55SJU - LHR
2 stops16h 35mAmerican Airlines
Deal found 15/4£828
Fri 25/414:05LHR - SJU
2 stops28h 45mAir Canada
Wed 21/501:05SJU - LHR
2 stops24h 30mAir Canada
Deal found 15/4£853

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 16 April 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

Mon 22/9

08:15-21:18

1 stop18h 03m

San Juan Luis Munoz Marin Intl

Sun 28/9

03:15-20:45

1 stop12h 30m

£483

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Tue 23/9

08:15-21:18

1 stop18h 03m

San Juan Luis Munoz Marin Intl

Mon 29/9

03:15-20:45

1 stop12h 30m

£508

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Thu 15/5

09:15-18:50

1 stop14h 35m

San Juan Luis Munoz Marin Intl

Thu 22/5

13:30-09:25

1 stop14h 55m

£534

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Fri 30/5

16:50-15:29

1 stop27h 39m

San Juan Luis Munoz Marin Intl

Fri 6/6

21:30-07:15

1 stop28h 45m

£583

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Mon 28/4

14:10-15:40

2 stops30h 30m

San Juan Luis Munoz Marin Intl

Thu 22/5

01:05-20:40

1 stop14h 35m

£688

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Tue 6/5

11:20-09:14

2 stops26h 54m

San Juan Luis Munoz Marin Intl

Tue 13/5

13:58-18:50

2 stops23h 52m

£728

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Fri 19/9

07:30-23:57

2 stops21h 27m

San Juan Luis Munoz Marin Intl

Sun 28/9

13:30-07:15

1 stop12h 45m

£826

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Wed 24/9

11:30-18:30

1 stop12h 00m

San Juan Luis Munoz Marin Intl

Tue 30/9

11:55-09:30

2 stops16h 35m

£828

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Sat 26/4

09:30-11:57

2 stops31h 27m

San Juan Luis Munoz Marin Intl

Wed 21/5

01:05-06:35

2 stops24h 30m

£856

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Tue 29/4

06:30-23:48

2 stops22h 18m

San Juan Luis Munoz Marin Intl

Sat 3/5

18:05-20:00

1 stop20h 55m

£885

Flights are sorted by cheapest return flights first.

Deals found on 14/4

Showing 1-10 of 16 results
1
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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 11 April 2025.

The best time to book flights from London Heathrow Airport to San Juan is 76 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, April is the cheapest month in which you can book a flight from London Heathrow Airport to San Juan (average of £631). Flying from London Heathrow Airport to San Juan in July is currently the most expensive (average of £1,027). 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 16 April 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 morning. If you’re flexible enough to do this you can expect to save up to 22% on your trip compared to booking a flight in the evening.

What is the cheapest day to fly from London Heathrow Airport to San Juan?

Use this chart to determine the cheapest time to fly return from Heathrow to San Juan. Price data was last updated on 16 December 2024.

Travellers seeking maximum savings on their London Heathrow Airport to San Juan flight should consider departing on Monday mornings when fares are most often at their lowest. Tuesday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

Rainfall in San Juan by month

Plan your trip to San Juan by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in San Juan ranges from 55.0 - 156.0 inches per month. November is typically the wettest month, when rainfall can reach 156.0 mm. March is typically the driest time to visit San Juan when rainfall is around 55.0 mm.

Temperature in San Juan by month

Plan your trip to San Juan by taking into account the average temperature totals by month.

If weather is an important factor for your trip to San Juan, use this chart to help with planning. For those seeking warmer temperatures, June is the ideal time of year to visit, when temperatures reach an average of 28.0 C. Travellers hoping to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 25.0 C).

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 16 April 2025.
Peruse reviews from past customers who have flown with Delta, United Airlines and Virgin Atlantic from London to San Juan to help guide your decision. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.

Entertainment

7.9

Overall

8.0

Comfort

7.9

Food

7.3

Boarding

8.2

Crew

8.5

Reviews

1 / 20
6.0
Good

Colin,Sept 2024

LHR - BOS

Delta One is very poor quality seating for first class. On multiple trips pieces have come off the seat. Staff and food have been good
8.0
Very Good

Entertainment

7.9

Overall

8.0

Comfort

7.9

Food

7.3

Boarding

8.2

Crew

8.5

Reviews

1 / 20
6.0
Good

Colin,Sept 2024

LHR - BOS

Delta One is very poor quality seating for first class. On multiple trips pieces have come off the seat. Staff and food have been good

Entertainment

7.9

Overall

8.0

Comfort

7.9

Food

7.3

Boarding

8.2

Crew

8.5

Reviews

1 / 20
6.0
Good

Colin,Sept 2024

LHR - BOS

Delta One is very poor quality seating for first class. On multiple trips pieces have come off the seat. Staff and food have been good

Entertainment

7.9

Overall

8.0

Comfort

7.9

Food

7.3

Boarding

8.2

Crew

8.5

Reviews

1 / 20
6.0
Good

Colin,Sept 2024

LHR - BOS

Delta One is very poor quality seating for first class. On multiple trips pieces have come off the seat. Staff and food have been good

Entertainment

7.9

Overall

8.0

Comfort

7.9

Food

7.3

Boarding

8.2

Crew

8.5

Reviews

1 / 20
6.0
Good

Colin,Sept 2024

LHR - BOS

Delta One is very poor quality seating for first class. On multiple trips pieces have come off the seat. Staff and food have been good

Entertainment

7.9

Overall

8.0

Comfort

7.9

Food

7.3

Boarding

8.2

Crew

8.5

Reviews

1 / 20
6.0
Good

Colin,Sept 2024

LHR - BOS

Delta One is very poor quality seating for first class. On multiple trips pieces have come off the seat. Staff and food have been good

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.
  • 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 Icelandair. Our recent data shows that you can find tickets from as low as £483 on this airline. Additional options worth looking into are JetBlue and Iberia, starting at £508 and £534 round-trip. Icelandair is currently priced 24% below the average price you’ll pay for this route.

  • What are the cheapest airlines to fly from London Heathrow Airport to San Juan one-way?

    The cheapest airline one-way is Iberia, with whom users have recently found tickets for as low as £494. However, be on the lookout for offers from Avianca and JetBlue, as they are both options that can get you from London Heathrow Airport to San Juan for a low price.

  • 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, April is the cheapest month in which you can book a flight from London Heathrow Airport to San Juan (average of £631). Flying from London Heathrow Airport to San Juan in July is currently the most expensive (average of £1,027). 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 16 April 2025.
AirlineCheapestAverageFlexibilityOn-time
FinnairCheapest£426Average£561FlexibilityNo cancel feeOn-time76%
Search Finnair flights
JetBlueCheapest£445Average£658FlexibilityNo cancel feeOn-time62%
Search JetBlue flights
IcelandairCheapest£455Average£571FlexibilityNo cancel feeOn-time76%
Search Icelandair flights
IberiaCheapest£510Average£685FlexibilityNo cancel feeOn-time77%
Search Iberia flights
British AirwaysCheapest£569Average£735FlexibilityNo cancel feeOn-time70%
Search British Airways flights
Virgin AtlanticCheapest£857Average£1,145FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights

Fly with Cheapflights

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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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