This note discusses the new plastic packaging tax introduced by the UK. The first part of this note is descriptive: it explains how the plastic packaging tax will operate in practice by means of a discussion of the tax’s main features. The second and third parts provide critical comments on two main aspects of the new plastic packaging tax. The second part critically assesses the policy objective of the plastic packaging tax. The third part evaluates the legal design of the tax by highlighting that some of its design features seem inconsistent with its policy objective. Finally, the fourth part concludes.