The Theory of Planned Behaviour proposes that attitudes, subjective norms, and perceived behavioural control predict physical activity (PA) intentions and subsequently behaviour (Ajzen, 1991). Recently, the complexity of the subjective norm-intentions relationship was highlighted by Kim et al. (2019), who found the relationship between normative beliefs (i.e., perceptions of normative pressure) and PA intentions to be stronger for individuals with higher motivation to comply with those normative beliefs. However, individuals with lower motivation to comply still had moderate levels of PA intentions regardless of their level of normative beliefs. Interpreting this finding, a possible buffer against normative beliefs is the degree to which individuals' PA behaviours are already intrinsically regulated. The current study examined differences in the relationship between normative beliefs and PA intentions, as moderated by motivation to comply, for individuals with low vs. high intrinsic regulation. Analysis of data gathered from 204 undergraduate students (173 females, 30 males, 1 non-binary) at two time points revealed that for individuals with high intrinsic regulation, normative beliefs positively predicted PA intentions (b = .29, p = .006). However, for individuals with low intrinsic regulation, there was a significant interaction between normative beliefs and motivation to comply with respect to predicting intentions (b = .16, p = .026). Specifically, normative beliefs negatively predicted intentions for PA (b = -.49, p = .008) when individuals had lower motivation to comply. These findings indicate that individuals' existing levels of intrinsic regulation should be considered when attempting to exert social influence on PA behaviours.