“Water-resistant” solar: what it really means
Natali Profumeria · 1 min read · November 1, 2026
“Water resistant”, “water resistant”, “very water resistant”: these are reassuring labels, but we often interpret them too optimistically.
What the test says
In Europe, a sunscreen can be called water resistant if, after two 20-minute immersions, it retains at least half of its protection. It is very water resistant if it retains it after four 20-minute immersions.
So even the most resistant product loses part of its effectiveness in water: it is resistant, not waterproof.
The real enemy is the towel
More than water, it is rubbing that removes the protection: drying off with a towel, sand, sweat wiped off with hands. For this reason, sunscreen should be reapplied after every swim.
When it is useful
For sports, for children who go in and out of the water, for hot days when you sweat a lot: a water-resistant sunscreen protects better between applications. But the rule remains the same: reapply every two hours and after every swim.
Frequently asked questions
What does water-resistant sunscreen mean?
That after two 20-minute immersions, it retains at least half of the protection. “Very water resistant” means that it retains it after four immersions.
Should water-resistant sunscreen be reapplied after swimming?
Yes: in water it still loses part of the protection, and drying off removes even more.
Is there a waterproof sunscreen?
No: every sunscreen loses part of its protection in water. The correct labels are “water resistant” or “very water resistant”, and the product must still be reapplied after swimming.