Question: How Long Does Mascara Last? Answer: Mascara is one makeup product in your bag that you want to keep tabs on. It’s a breeding ground for bacteria. Most mascaras with a tube and a wand have an antibacterial agent in them that last about 6 weeks making you safe for at least a couple months and likely safe up to 4. You risk eye infection the longer you keep the product. If you notice the smell changes or the texture changes, throw it out. It’s not worth it.