A convenient metal-free procedure for the preparation of benzyl (phenyl) γ- and δ-lactones is illustrated. This method is based on the photochemical generation of phenyl cations and their reaction with 3, 4, or 5-alkenoic acids. This leads to a phenyl- or benzyl-substituted lactone by tandem formation of an aryl−C and C−O bond. The intermediacy of a phenonium ion imparts a full regio- and stereoselectivity to the reaction.