Sentences with plural expressions are compatible with distributive and collective interpretations. Adults generally prefer collective interpretations, whereas children do not. Dotlačil (2010) argues that the adult collective preference arises via an implicature. Adults can reason about alternative utterances with the distributive marker each , thereby ruling out distributive interpretations in favor of collective interpretations. Experiment 1 used the covered-box paradigm to investigate whether adults and children make the comparisons predicted by Dotlačil’s implicature account. Adults’ responses suggest that they made comparisons with internally generated alternatives, supporting the implicature account. Moreover, children seem to do so from around 11 years old onwards, after they have learned the distributive character of each . Experiment 2 excluded the possibility that our results in Experiment 1 were influenced by participants’ exposure to both collective and distributive pictures, making the collective interpretation more salient. Both experiments thus point towards an implicature underlying the adult collective preference.