Referenzpreis – Definition

The comparison price shown alongside a discounted price — under the Preisangabenverordnung, the lowest price charged in the last 30 days, not an arbitrary higher prior price.

Displaying an incorrect reference price is a legal risk, not just a design choice. Tying discount modules directly to a product's price history in the commerce system removes the risk of manually entered, outdated comparison prices. The 30-day lookback window creates a specific operational requirement easy to overlook when designing a discount module: the system needs to retain and query historical pricing reliably, and correctly identify the actual lowest price during that window even if the price changed multiple times within it. A discount module without this historical awareness will either display an incorrect price or require manual verification for every promotion.