This study investigates the main barriers to the implementation of the circular economy (CE) in the European Union (EU). It presents the first large-N study on CE barriers in the EU, involving 208 survey respondents and 47 expert interviews. The research finds that cultural barriers, particularly a lack of consumer interest and awareness and a hesitant company culture, are considered the main barriers by businesses and policy-makers. These are driven by market barriers, which are induced by a lack of synergistic governmental interventions to accelerate the transition towards a circular economy. Not a single technological barrier is ranked among the most pressing CE barriers. The study suggests that CE is a niche discussion among sustainable development professionals at this stage. Significant efforts are needed for the concept to maintain its momentum. The research highlights the importance of addressing cultural and market barriers rather than focusing solely on technological solutions. It also emphasizes the need for new intervention strategies to enable a transition towards a CE, particularly through government action to tackle market barriers such as low virgin material prices and high upfront investment costs. The study concludes that while the CE concept is gaining momentum, its implementation remains limited, and cultural barriers are a significant challenge. The findings suggest that a combination of policy interventions and cultural shifts are necessary to achieve a successful transition to a circular economy.This study investigates the main barriers to the implementation of the circular economy (CE) in the European Union (EU). It presents the first large-N study on CE barriers in the EU, involving 208 survey respondents and 47 expert interviews. The research finds that cultural barriers, particularly a lack of consumer interest and awareness and a hesitant company culture, are considered the main barriers by businesses and policy-makers. These are driven by market barriers, which are induced by a lack of synergistic governmental interventions to accelerate the transition towards a circular economy. Not a single technological barrier is ranked among the most pressing CE barriers. The study suggests that CE is a niche discussion among sustainable development professionals at this stage. Significant efforts are needed for the concept to maintain its momentum. The research highlights the importance of addressing cultural and market barriers rather than focusing solely on technological solutions. It also emphasizes the need for new intervention strategies to enable a transition towards a CE, particularly through government action to tackle market barriers such as low virgin material prices and high upfront investment costs. The study concludes that while the CE concept is gaining momentum, its implementation remains limited, and cultural barriers are a significant challenge. The findings suggest that a combination of policy interventions and cultural shifts are necessary to achieve a successful transition to a circular economy.