Why must German political parties win at least 5 percent of the vote to gain Bundestag representation?

The 5 percent threshold for Bundestag representation is a deliberate feature of the German electoral system designed to ensure political stability.

Historically, the proliferation of numerous small political parties contributed to the collapse of the Weimar Republic in 1933. To prevent a return to such fragmentation, the 5 percent rule serves as an effective instrument to exclude radical parties and prevent the formation of splinter parties that could hinder effective governance.1

By requiring parties to secure at least 5 percent of the national vote—or win at least three constituencies—the system encourages the consolidation of political interests. This structure helps maintain a legislature that reflects a broad consensus of opinion while ensuring that the government remains functional, typically through the formation of coalition governments composed of larger, more stable parties.12