​We examine investors’ herding/anti-herding behavior in the US stock and corporate bond markets and their impact on stock-bond return correlation. Corporate bonds exhibit herding, with stocks displaying anti-herding. Bond herding and stock anti-herding are weakly related, with each significantly dampening the stock-bond return correlation. This effect is largely driven by their irrational components, affecting mostly the correlation of noise-driven stock and bond return elements, more so during periods of elevated uncertainty, optimistic sentiment and excessively positive economic performance. As the irrational forces in each asset class (stocks; bonds) countervail each other, this implies greater stability and resilience for the financial system.