Hair styling powders typically last for about 6 to 12 months, depending on the brand and formulation. However, it's important to check the specific expiration date mentioned on the product packaging. Over time, the efficacy of the powder may diminish, and it may also become less effective in providing the desired styling results. Additionally, proper storage, such as keeping the powder in a cool, dry place away from direct sunlight, can help extend its shelf life.