Yes, fragrance oils do expire. Over time, a scent can fade, change, or develop an off smell due to oxidation or degradation. This process happens faster if the oils are exposed to heat, light, or air. Most fragrance oils last around 1 to 3 years, but the exact lifespan depends on the ingredients and storage conditions. To keep fragrance oils fresh for as long as possible, store fragrance oils in a cool, dark place with the lids tightly closed. If an oil smells different or looks cloudy or separated, it’s likely expired.