How often should I reapply sunscreen?

Even though we know this already, recent studies have revealed that peoples approach to sunscreen is often slap-dash, when applying sunscreen properly before going outdoors and then not reapplying every two hours as recommended.

There are many factors that can affect sunscreens ability to be as effective as long as they are supposed to be. These include,

  • Apply enough sunscreen – an average size adult requires 6 full teaspoons to cover their body and achieve protection indicated on the label.
  • Sunscreen should be applied 20-30 minutes before sun exposure to allow the ingredients to bind to the skin.
  • Sweating, swimming and clothes rubbing against the skin causes the sunscreen to wear off faster.
  • Throw out last year’s sunscreen, some sunscreens have a shelf life between 2-3 years however due to the unstable nature, bottles open for longer than one year should be disposed of.
  • Check expiration dates on the sunscreen label, if expiration date has passed, throw out the sunscreen, as active ingredients in sunscreen can deteriorate over time.
  • Read the suggested storage conditions on the label.

Remember! Sunscreen should not be your main method of sun protection, but rather used in conjunction with other methods of sun protection such as wearing sun protective clothing, hats, sunglasses and seeking shade particularly between 11am-3pm.

Related: No sunscreen can provide 100% sun protection.


We want everyone in Ireland to learn to Protect & Inspect their skin! Download our short guide, written with hospital-based dermatologists, to checking your skin.   

Melanoma is on the rise in Ireland: see the facts in these info-graphics – Melanoma Skin Cancer and Solar UV Radiation

Click for more more about Protect & Inspect!

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