Cheap flights from London Heathrow Airport to San Juan from £352
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from London Heathrow Airport to San Juan departing on 8/9. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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How to get the cheapest flight ticket from London Heathrow Airport to San Juan
Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip
What is the cheapest month to fly to San Juan?
The cheapest month to fly to San Juan from London Heathrow Airport is in September. Flight prices, which tend to average around £486, are often lower during this time because this is during the off-season. If you aren’t able to travel during the month of September, then book flights to San Juan from London Heathrow Airport during January instead. Flights to San Juan in January, while not as cheap as those in September, still average around £548.
What is the cheapest day to depart on your flight to San Juan?
The cheapest day to depart on your flight to San Juan is on a Monday when prices can be found for as low as £521. This is often the case because there is less demand to fly during this day of the week. The most expensive day to fly to San Juan is Saturday, with ticket prices averaging around £635.
What is the cheapest time of day to depart on your flight to San Juan?
In the morning is the cheapest time of day to fly from London Heathrow Airport to San Juan when you can find flight prices for as low as £576. Flying to San Juan in the morning is an ideal time because this is during off-peak travel hours. Flights in the afternoon are often more expensive, with an average ticket price of £823.
How far in advance should I book a flight to San Juan?
You are more likely to see cheaper flights to San Juan from London Heathrow Airport when booking weeks ahead of your departure date. In general, you can expect to find flights to San Juan for around £635 when searching weeks before you fly. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to San Juan from London Heathrow Airport for as low as £501 on momondo.
What is the cheapest airline that flies from London Heathrow to San Juan?
Icelandair, Avianca, and JetBlue are the most popular carriers operating from London Heathrow to San Juan
Which airlines fly to San Juan?
Finnair, Iberia and Icelandair are the top three most popular airlines that fly to San Juan from London Heathrow Airport according to our data. Finnair is the first choice among our users, with 44% of people opting to fly with this airline when travelling to San Juan. Keep in mind that there are 6 different airlines that fly to San Juan on a routine basis, so you have a few additional options to choose from.
Cheap London Heathrow Airport to San Juan flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from London Heathrow Airport to San Juan
How far is London Heathrow to San Juan by plane?
The distance between London Heathrow and San Juan is about 4182.0 mi. A reasonable flight in good conditions will take 12h 39m.
When did momondo last update prices for flights from London Heathrow Airport to San Juan?
Prices for flights from London Heathrow Airport to San Juan are updated daily.
How many operators does momondo search for flights from London Heathrow Airport to San Juan?
As of July 2025, there are 6 operators available to choose from for flights from London Heathrow Airport to San Juan.
How old do you have to be to fly from London Heathrow Airport to San Juan?
The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from London Heathrow Airport to San Juan.
What documentation or ID do you need to fly to San Juan?
The required travel and health documents for your San Juan trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at San Juan. We recommend that you seek guidance from your airline or a reliable third party such as IATA.
Best airlines flying from London Heathrow Airport to San Juan
Compare and see reviews for airlines that fly from London Heathrow Airport to San Juan with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom £353 | Free Cancellation | Rating 7.4 654 reviews | |||
| PriceFrom £406 | Free Cancellation | Rating 7.3 2,916 reviews | |||
| PriceFrom £410 | Free Cancellation | Rating 7.6 1,306 reviews | |||
| PriceFrom £444 | Free Cancellation | Rating 7.0 514 reviews | |||
| PriceFrom £504 | Free Cancellation | Rating 7.0 2,820 reviews | |||
| PriceFrom £530 | Free Cancellation | Rating 6.6 7,093 reviews |
Why use momondo?
Why should I use momondo to find a flight deal from London to San Juan?
To find the flight that best suits your needs, momondo gathers a range of flights from a large pool of different airlines and agents; you can then use our insights and filters to find and book the right flight to San Juan from London.
Can I find flights from London to San Juan with flexible booking policies on momondo?
Yes. momondo allows you to filter the results for London to San Juan flights to just show those with flexible booking policies.
How can momondo help me find flights from London to San Juan?
momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from London to San Juan.
I’m not ready to book a flight from London to San Juan right now. Can momondo alert me if prices change?
Yes. momondo can track prices for London to San Juan flights and alert you when they change. Perform a search to set up the price alert. All that is required is a valid email address.