This study examined conversations about maths (maths talk) between mothers and their preschoolers in the home setting. Naturalistic conversational data on 40 mother-child dyads from a Midwestern area in the United States were gathered using the Language ENvironment Analysis System (LENA). A sample of up to four hours of talk during shared meals for each dyad was transcribed, coded and analysed in terms of maths talk. The results showed that all mothers and children engaged in maths talk during the hours recorded, though the amount of maths talk varied from zero to 308 utterances per hour. The main types of maths input involved naming numbers, counting, using ordinal numbers and referring to numbers in the context of time. Most of the maths talk was initiated and dominated by mothers. The results of this study underscore the ways mothers socialize mathematics with their preschoolers in interactions during meals and provide support for the use of voice recordings to study maths input in the home environment.