The European Union’s (EU) approach to safeguarding seed quality and ensuring agricultural productivity includes a range of regulatory measures related to seed marketing, including the restriction of market access to seed varieties that are properly certified. In order for varieties to be properly certified, they have to be registered in a Plant Variety Catalogue. EU seed laws, and their Member State implementation, have traditionally favoured uniform crop production of commercialised breeds over conservation varieties, which has been a contributing factor to crop genetic erosion. The United States’ (U.S.) approach to seed marketing regulation is often presented as an alternative model to the EU’s approach. In the United States, any seed can be indistinctly marketed if properly labelled. In this regulatory framework, certification and registration of seed is voluntary. In light of the continued issues regarding crop genetic erosion and the recent developments in EU seed law reform, this article examines the key elements of both regimes and considers their different approaches to market access for conservation varieties. The most important differences relate to in truth-in-labelling (U.S.) and ex ante quality control mechanisms (EU). These differences highlight that EU and U.S. seed laws must be placed in their respective broader regulatory context and that their relative comparability hinges on policy aims related to seed quality. This raises the broader question as to what the key policy aims of seed laws are and whether these oft-compared regimes are in fact analogous in terms of goals and structure.