Find flights
When to book
Airlines
FAQs

Cheap flights from London Heathrow Airport to San Juan from £251

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 25/4. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — SJU
30 Mar — 6 Apr1
1 adult

Cheapflights Tip: The best prices from London Heathrow to San Juan are usually found in September or April, 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 25 March 2025.

Round-trip from

£507

One-way from

£251

Popular in

July

Cheapest in

September

Average price

£588
Finnair
  • Finnair
  • 9/9-24/9
  • 2 total stops
  • 31h 25m total
  • London to San Juan
Search Deals
25/4
  • 25/4
  • 2 total stops
  • 41h 36m total
  • London to San Juan
Search Deals
Highest demand for flights based on searches. 17% potential increase in price (£107 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease (£16 potential savings vs. average return price).
Search Deals
Average for round-trip flights in March 2025
Search Deals

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 25 March 2025.

Tue 9/907:45LHR - SJU
1 stop15h 45mFinnair
Wed 24/913:55SJU - LHR
1 stop15h 40mFinnair
Deal found 25/3£507
Wed 3/911:30LHR - SJU
1 stop12h 00mIberia
Thu 18/908:30SJU - LHR
1 stop19h 55mIberia
Deal found 25/3£507
Tue 9/908:15LHR - SJU
1 stop22h 30mIcelandair
Tue 23/903:15SJU - LHR
1 stop12h 30mIcelandair
Deal found 24/3£509
Mon 3/1108:25LHR - SJU
1 stop18h 35mJetBlue
Tue 11/1101:59SJU - LHR
1 stop14h 46mJetBlue
Deal found 24/3£510
Sat 3/519:40LHR - SJU
1 stop19h 20mMultiple Airlines
Thu 8/506:20SJU - LHR
1 stop19h 10mMultiple Airlines
Deal found 25/3£554
Thu 6/1112:25LHR - SJU
2 stops19h 55mTAP AIR PORTUGAL
Sat 15/1106:15SJU - LHR
2 stops25h 10mTAP AIR PORTUGAL
Deal found 24/3£670
Wed 23/412:15LHR - SJU
2 stops37h 23mUnited Airlines
Tue 29/401:05SJU - LHR
1 stop14h 35mUnited Airlines
Deal found 24/3£691

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 25 March 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

Tue 9/9

07:45-18:30

1 stop15h 45m

San Juan Luis Munoz Marin Intl

Wed 24/9

13:55-10:35

1 stop15h 40m

£507

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Wed 3/9

11:30-18:30

1 stop12h 00m

San Juan Luis Munoz Marin Intl

Thu 18/9

08:30-09:25

1 stop19h 55m

£507

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Tue 9/9

08:15-01:45

1 stop22h 30m

San Juan Luis Munoz Marin Intl

Tue 23/9

03:15-20:45

1 stop12h 30m

£509

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Wed 23/4

08:25-00:06

1 stop20h 41m

San Juan Luis Munoz Marin Intl

Tue 29/4

03:28-20:45

1 stop12h 17m

£520

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Sat 3/5

19:40-10:00

1 stop19h 20m

San Juan Luis Munoz Marin Intl

Thu 8/5

06:20-06:30

1 stop19h 10m

£554

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Wed 23/4

12:15-20:38

2 stops37h 23m

San Juan Luis Munoz Marin Intl

Tue 29/4

01:05-20:40

1 stop14h 35m

£691

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Fri 25/4

19:50-08:26

2 stops41h 36m

£251

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Mon 19/5

09:15-18:50

1 stop14h 35m

£491

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Fri 25/4

22:05-16:50

1 stop23h 45m

£558

LondonSan Juan

LHR - SJU

LHRSJU

London Heathrow

Thu 8/5

08:25-18:05

1 stop14h 40m

£575

Flights are sorted by cheapest return flights first.

Deals found on 25/3

Showing 1-10 of 14 results
1
2

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 21 March 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 25 March 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 25 March 2025.
Peruse reviews from past customers who have flown with Finnair, Air France and United Airlines 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.
Finnair
7.6
Good
1,266 reviews
Check prices

Crew

8.1

Entertainment

6.9

Boarding

7.6

Comfort

7.4

Food

6.7

Overall

7.6

Reviews

1 / 20
2.0
Mediocre

Rowland,Dec 2024

HEL - HKG

Finnair, a large European airline, have a very poor boarding practice whereby they collect every passenger waiting at the gate into an even smaller closed in area after checking passports (again) and boarding cards - then simply open the boarding causing a crowd crush as ALL passengers attempt to board all at once. Surely a more controllable method these days is to board via seat row numbers?
Finnair
7.6
Good
1,266 reviews
Finnair
7.6
Good
1,266 reviews
Check prices

Crew

8.1

Entertainment

6.9

Boarding

7.6

Comfort

7.4

Food

6.7

Overall

7.6

Reviews

1 / 20
2.0
Mediocre

Rowland,Dec 2024

HEL - HKG

Finnair, a large European airline, have a very poor boarding practice whereby they collect every passenger waiting at the gate into an even smaller closed in area after checking passports (again) and boarding cards - then simply open the boarding causing a crowd crush as ALL passengers attempt to board all at once. Surely a more controllable method these days is to board via seat row numbers?
Air France
7.4
Good
1,423 reviews
Finnair
7.6
Good
1,266 reviews
Check prices

Crew

8.1

Entertainment

6.9

Boarding

7.6

Comfort

7.4

Food

6.7

Overall

7.6

Reviews

1 / 20
2.0
Mediocre

Rowland,Dec 2024

HEL - HKG

Finnair, a large European airline, have a very poor boarding practice whereby they collect every passenger waiting at the gate into an even smaller closed in area after checking passports (again) and boarding cards - then simply open the boarding causing a crowd crush as ALL passengers attempt to board all at once. Surely a more controllable method these days is to board via seat row numbers?
United Airlines
7.4
Good
8,605 reviews
Finnair
7.6
Good
1,266 reviews
Check prices

Crew

8.1

Entertainment

6.9

Boarding

7.6

Comfort

7.4

Food

6.7

Overall

7.6

Reviews

1 / 20
2.0
Mediocre

Rowland,Dec 2024

HEL - HKG

Finnair, a large European airline, have a very poor boarding practice whereby they collect every passenger waiting at the gate into an even smaller closed in area after checking passports (again) and boarding cards - then simply open the boarding causing a crowd crush as ALL passengers attempt to board all at once. Surely a more controllable method these days is to board via seat row numbers?
Virgin Atlantic
7.4
Good
634 reviews
Finnair
7.6
Good
1,266 reviews
Check prices

Crew

8.1

Entertainment

6.9

Boarding

7.6

Comfort

7.4

Food

6.7

Overall

7.6

Reviews

1 / 20
2.0
Mediocre

Rowland,Dec 2024

HEL - HKG

Finnair, a large European airline, have a very poor boarding practice whereby they collect every passenger waiting at the gate into an even smaller closed in area after checking passports (again) and boarding cards - then simply open the boarding causing a crowd crush as ALL passengers attempt to board all at once. Surely a more controllable method these days is to board via seat row numbers?
JetBlue
7.3
Good
2,923 reviews
Finnair
7.6
Good
1,266 reviews
Check prices

Crew

8.1

Entertainment

6.9

Boarding

7.6

Comfort

7.4

Food

6.7

Overall

7.6

Reviews

1 / 20
2.0
Mediocre

Rowland,Dec 2024

HEL - HKG

Finnair, a large European airline, have a very poor boarding practice whereby they collect every passenger waiting at the gate into an even smaller closed in area after checking passports (again) and boarding cards - then simply open the boarding causing a crowd crush as ALL passengers attempt to board all at once. Surely a more controllable method these days is to board via seat row numbers?

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 Finnair. Our recent data shows that you can find tickets from as low as £507 on this airline. Additional options worth looking into are Iberia and Icelandair, starting at £507 and £509 round-trip. Finnair is currently priced 23% 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 £491. 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

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

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 25 March 2025.
AirlineCheapestAverageFlexibilityOn-time
FinnairCheapest£437Average£574FlexibilityNo cancel feeOn-time76%
Search Finnair flights
JetBlueCheapest£455Average£691FlexibilityNo cancel feeOn-time62%
Search JetBlue flights
IcelandairCheapest£465Average£570FlexibilityNo cancel feeOn-time76%
Search Icelandair flights
IberiaCheapest£520Average£693FlexibilityNo cancel feeOn-time77%
Search Iberia flights
British AirwaysCheapest£582Average£765FlexibilityNo cancel feeOn-time70%
Search British Airways flights
Virgin AtlanticCheapest£876Average£1,170FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travellers can enjoy low prices and a wide availability of flights to their desired destinations.

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

Cheapflights helps you search for flights from Heathrow to San Juan via 900+ travel sites so you don’t have to. After performing a flight search, users can also filter their flight selection by filtering for price, number of stops, airlines, and so on.

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

Cheapflights simply makes it quick and affordable to book flights from Heathrow to San Juan by bringing together all flight options from hundreds of airlines and agencies online — and put it in one place for you to choose from. Plus, Cheapflights is 100% free to use for all.

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.

Can Cheapflights notify me if prices for flights from Heathrow to San Juan become cheaper?

Yes, and it’s super simple to set up. Click the bell icon next to the flight deals above and provide a valid email address to enable Price Alerts. That’s it!

100% Free
Cheapflights is completely free to use, so you can start saving the moment you arrive.
Book with Flexibility
Our users can plan ahead with confidence and find flights with no change fees
Travel Smart
Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.