Peer observation can influence social norm perceptions as well as behavior in various moral domains, but is the tendency to be influenced by and conform with peers domain-general? In an online experiment (N = 815), we studied peer effects in honesty and cooperation and tested the individual-level links between these two moral domains. Participants completed both honesty and cooperation tasks after observing their peers. Consistent with the literature, separate analysis of the two domains indicated both negative and positive peer influences in honesty and in cooperation, with negative influences tending to be stronger. Behavioral tests linking the two domains at the individual-level revealed that cooperative participants were also more hones...