We study how heterogeneous attention to inflation affects monetary policy transmission. Firstly, we empirically show that households’ attention to inflation varies with socio-demographic characteristics using household-level survey data for the US and Australia. Given that some prices are salient, we also measure shock-specific attention. Secondly, we study how differential attention to inflation through the formation of inflation expectations affects monetary policy transmission. For this purpose, we introduce a sparsity-based maximization operator into a two-asset HANK model calibrated to match empirical evidence for both countries.