Numerous studies have observed kin-biased social associations in a variety of species. Many of these studies have focussed on species exhibiting parental care, which may facilitate the transmission of the social environment from parents to offspring. This becomes problematic when disentangling whether kin-biased associations are driven by kin recognition, or are a product of transmission of the social environment during ontogeny, or a combination of both. Studying kin-biased associations in systems that lack parental care may aid in addressing this issue. Furthermore, when studying kin-biased social associations it is important to differentiate whether these originate from preferential choice or occur randomly as a result of habitat use or limited dispersal. Here, we combined high-resolution SNP data with a long-term behavioural dataset of a reptile with no parental care to demonstrate that eastern water dragons (Intellagama lesueurii) bias their non-random social associations toward their kin. In particular, we found that, while the overall social network was not linked to genetic relatedness, individuals associated with kin more than expected given availability in space, and also biased social preferences towards kin. This result opens important opportunities for the study of kinship-driven associations without the confounding effect of vertical transmission of social environments. Furthermore, we present a robust multiple-step approach for determining whether kin-biased social associations are a result of active social decisions, or random encounters resulting from habitat use and dispersal patterns.