Aim and objective: The objective of this study was to evaluate and compare the antimicrobial efficacy of low-fluoride and fluoride-free dentifrices against Streptococcus mutans. Materials and methods: The antimicrobial efficacy of four commercially available low-fluoride child formula dentifrices and four fluoride-free dentifrices against S. mutans was determined using the agar diffusion test. Fifty microliters of various dilutions (1:1, 1:2, 1:4) of each dentifrice were inoculated on the assigned plates under aseptic conditions. Saline was taken as negative control and 0.2% chlorhexidine was considered as a positive control. The plates were incubated at 37°C for 24 hours and the zone of inhibition around the wells was measured. Results: All the tested low-fluoride dentifrices showed varying degrees of antimicrobial activity against S. mutans with F2 (Pediflor®) and F4 (Cheerio™) showing greater zones of inhibition when compared to F1 (Colgate®kids) and F3 (Kidodent). When the mean zones of inhibition produced by non-fluoridated dentifrices were compared with that of fluoridated dentifrices, no statistically significant difference was noted between NF1, NF3, NF4, and F2, F4. The antibacterial activity of F1 and F3 was significantly lower when compared to others. However, no antibacterial activity was noted with NF2. Conclusion: Both low-fluoride and fluoride-free formulations tested in the study exhibited antimicrobial activity against S. mutans. In very young children where the risk of fluorosis is of concern, fluoride-free formulations can be considered as safe alternatives to fluoride formulations. Clinical significance: Several dentifrices, both fluoride-free and low-fluoride formulations, are being aggressively marketed for young children. Though these toothpastes are being very commonly used by young parents for their infants and toddlers, there is very little published literature available on their antimicrobial activity and this study focuses on addressing this.