For children with normal hearing (NH), early communication skills predict vocabulary, a precursor to grammar. Growth in early communication skills of infants with cochlear implants (CIs) was investigated using the Early Communication Indicator (ECI), a play-based observation measure. Multilevel linear growth modelling on data from six ECI sessions held at three-monthly intervals revealed significant growth overall, with a non-significant slower growth rate than that of children with NH (comparison age centred at 18 months). Analyses of gesture use and of nonword vocalisations revealed the CI group used significantly more of each, with more rapid growth. In contrast, the CI group used significantly fewer single words and multiword utterances, and with slower growth. Maternal education and time to achieve consistent CI use impacted significantly on growth for the CI sample. The results indicate that progression to vocabulary by young CI users can be supported by encouraging their use of prelinguistic communication.