usually around 5 years.. but it all depends on the storage condition... I remembered my dad stored a box of Klasse stuff for over 8 years before and they're fine, but that's because the bottles are all sealed tight and far from heat and moisture... opened products may not last more than 2-3years, I believe... but honestly, I don't have any clue as to how long stuff will last given the variables like your storage area, how well it's sealed, etc...