This guidance provides recommendations on how to use stability data generated in accordance with the principles detailed in the ICH guidance Q1A(R2) Stability Testing of New Drug Substances and Products (parent guidance) to propose a retest period or shelf life in a registration application. This guidance describes when and how extrapolation can be considered when proposing a retest period for a drug substance or a shelf life for a drug product that extends beyond the period covered by available data from the stability study under the long-term storage condition (long-term data).