With another scorching Spanish summer coming to a close, a swimming pool certainly feels valuable. But how much does having one actually add to the price of a property? The answer, according to new research, is: it depends enormously on where you live.

A recent study by property portal pisos.com comparing homes with and without swimming pools across Spain’s 50 provinces found some extraordinary differences in asking prices.

From almost nothing to more than 300%

At the extreme end of the scale is Zamora, where a 100 sqm property with a pool has an average asking price of €222,296, compared with just €54,639 without one. That implies a remarkable pool premium of 307%.

Zamora isn’t alone. According to the study, properties with pools are more than twice as expensive as those without them in 12 Spanish provinces. The biggest gaps after Zamora were found in Cáceres (+276%), Ourense (+230%), Huesca (+212%) and Zaragoza (+159%).

The figures don’t mean that adding a swimming pool to an existing property will suddenly treble its value. The problem is that they are not necessarily comparing like with like.

As Ferran Font, Director of Studies at pisos.com, explains, in many inland provinces properties with pools tend to be detached houses with land in rural or suburban locations. Homes without pools are more likely to be flats and other fundamentally different types of property.

In other words, much of the apparent “pool premium” is actually a property-type premium.

Where pools are normal, the premium shrinks

The picture is very different in coastal markets where swimming pools are commonplace. Alicante has the smallest price difference in Spain at just 2.7%, followed by Málaga at 11.9% and Granada at 13.7%. Barcelona comes in at 27.3%.

That makes intuitive sense. In areas dominated by holiday homes and residential developments with communal pools, having access to a pool is nothing unusual. Buyers may expect one, so its presence does relatively little to distinguish one property from another.

The pisos.com figures therefore don’t give us a reliable answer to the question “How much would adding a pool increase the value of my home?” You would need genuine comparable sales of otherwise similar properties with and without pools to answer that properly.

What they do show is that a pool can be an important differentiator in the Spanish property market – but its value depends heavily on location, property type and how unusual pools are in the local market. Sometimes a pool is a luxury. In other places, it’s practically part of the uniform.