Preschool children with cerebral palsy (CP) with no or unintelligible speech need augmentative and alternative communication (AAC), but not all children needing AAC have access to it. This study describes the use and perceived benefit of AAC and explores factors associated with receiving AAC interventions. Using a cross-sectional design, we combined parent-reported data with data from the Norwegian Quality and Surveillance Registry for Cerebral Palsy (NorCP). Communication, speech and hand function was classified according to the Communication Function Classification System (CFCS), Viking Speech Scale (VSS), and Manual Ability Classification System (MACS), accordingly. The need for AAC was defined as Levels III-V on the CFCS, without simultaneous classification at VSS Level I, and/or Levels III-IV on VSS. Parents reported on child- and family-directed AAC interventions using the Habilitation Services Questionnaire. Of the 95 children (42 females) with CP (M = 39.4 months, SD = 10.3), 14 had communication aids. Of the 35 children (31.4%) defined as needing AAC, 11 had been provided with communication aids. Parents of children with a communication aid reported satisfaction with and frequent use of the aid. Children at MACS Level III-V (OR = 3.4, p = 0.02) or with epilepsy (OR = 8.9, p < 0.01) were most likely to have received an AAC intervention. The low proportion of children receiving communication aids indicates an unmet need for AAC interventions among preschool children with CP.