This is a product purchased from the official website. I'm selling it at a discounted price because I have too much stock due to a subscription. I believe it's been about a year since I purchased it. According to the official website, the unopened expiration date is 3 years. Sheet mask containing Vitamin C derivative. - Brand: N organic - Product Name: Enrich & Concentrate Mask - Contents: 1 sheet x 2 packs - Features: Contains Vitamin C derivative - Made in Japan Thank you for looking.