Child-directed speech (CDS), compared to speech between adults, shows a higher amount of repetitiveness, particularlyof sequences of utterances with self-repetitions. This phenomena, known as variation sets, has been found to be beneficialfor learning. Although previous findings indicated socio-economic status (SES) effects on the quantity of variation sets,they were based on data from child-parent dyadic interactions in play situations. Given that SES comprises interrelatedfactors affecting childrens quotidianity, here we examine SES effects on the use of variation sets in long recordings ofthe family naturalistic environment of 30 low and middle SES Argentinian children (8 to 20 months). Variation sets wereautomatically extracted from CDS provided by all the participants. Results demonstrated the effects of two factors relatedto SES-differences: while parents education showed a positive relation to the quantity and extension of variation sets, thenumber of people living in the household influenced it negatively.