Lifespan depends on how and how often you use your COMPLY ULTRA tips. Typically, the average lifespan is about 3-4 months per pair of COMPLY ULTRA FOAM tips. Body chemistry (oils and earwax) and the environment you use and store the tips in all affect how long your tips will last. To make your tips last the longest, make sure to always "prep the tip". This involves compressing the foam before inserting them into your ears. Also, clean your tips occasionally, and store the tips and earbuds in a case while not in use. Replace your tips when they start to "flake", tear, or lose their memory foam properties (for example, the foam expands quickly rather than slowly). You can purchase replacement and additional Comply foam tips from www.complyfoam.com.