The arrival of the Anthropocene requires a profound rethinking of business accountability. A central challenge in this age is the possibility of pushing past planetary boundaries, which may irreversibly propel the Earth system into a new equilibrium that is less hospitable for human civilization. Businesses drive many of the processes contributing to such boundaries, and are powerful political actors who may shape or obstruct the necessary transformations to our socio‐economic systems. We therefore need to reconsider their accountability, focused on the following guiding question: Who (in business) should be accountable to whom for what? The answer to this question has important implications for environmental policy and governance. Drawing on a range of recent conceptual and policy developments, I present four major lines of thinking for reconsidering business accountability in the Anthropocene context: to rethink the purpose of business; to acknowledge companies' expanded but shared accountability for productive activities; to heighten collective and individual liability for past and future actions linked to overshooting planetary boundaries; and to recognize business accountability for influencing political and societal processes. Each of these lines of thinking imply policy changes related to, inter alia, corporate governance, due diligence, liability, and lobbying laws. I further call on businesses to actively participate in the large‐scale transformation necessary to keep within planetary boundaries by changing not only their production processes, but also product portfolios, business models, legal forms, and political and societal engagement; and highlight avenues for future research.