Merchant Support Questions & Answers Is STAN unique? STAN is a 6-digit number that is unique only for 24 hours after purchase. Therefore, STAN + date (timestamp) is unique. Last Updated: 12 months ago in Questions & Answers Did this article answer your question? Related Articles Brand guidelines for MasterCard and VISA I didn't receive "Forgot password" e-mail Add new currency Supported currencies What is Open Banking? What is processing account?