The transition to a circular economy (CE) is essential for achieving sustainability goals by minimizing waste, optimizing resource use, and extending product lifecycles. Digital Technologies (DTs) serve as key enablers of this transition, facilitating automation, data-driven decision-making, and continuous improvement in CE. However, current notions of smart and digital circularity often focus on technological functionalities without explicitly addressing how DTs can act as means to enable CE solutions that then support sustainable development. This conceptual gap calls for a more integrated approach that aligns CE, digitalization, and sustainability outcomes. This paper systematically reviews the literature at the intersection of DTs and CE, identifying emerging themes and research opportunities. 76 peer-reviewed publications were identified and reviewed based on the DTs applications supporting CE adoption. The findings identify six main research themes, including DTs applications in CE adoption, enablers and barriers to CE adoption with the support of DTs applications, frameworks and models towards a digital CE, business models leveraging digital DTs to support CE, research propositions on DTs applications supporting CE, and DTs applications as solutions to CE adoption throughout product lifecycle. This study also introduces the concept of ‘intelligent circular,’ that integrates circularity, digitalization, and intelligence as the future direction of CE. Eleven research opportunities are proposed including emphasis on the need for empirical evidence, impact evaluation, performance measurement, and system-based approaches. Finally, the paper provides a foundation for advancing the CE transition to intelligent circular, contributing to the development of sustainable, data-driven, and resilient industrial systems.