Same-store sales is a business term that refers to the difference in revenue generated by a retail chain’s existing outlets over a certain period (often a fiscal quarter or a particular shopping season), compared to an identical period in the past, usually in the previous year. By comparing sales data from existing outlets (that is, by excluding new outlets or outlets which have since closed), the comparison is like-to-like and avoids comparing data that are fundamentally incomparable. This financial and operational metric is expressed as a percentage.

Same-store sales are also known as comparable store sales, identical store sales or like-store sales.

Same-store sales are widely reported by publicly-owned retail chains as a key element of their operational results. For chains that are growing quickly by opening new outlets, same-store sales figures allow analysts to differentiate between revenue growth that comes from new stores and growth from improved operations at existing outlets.