We evaluate the impacts of a randomised job fair intervention in which jobseekers and employers can meet at low cost. The intervention generates few hires, but it lowers participants’ expectations and causes both firms and workers to invest more in search as predicted by a theoretical model; this improves employment outcomes for less educated jobseekers. Through a unique two-sided belief-elicitation survey, we confirm that firms and jobseekers have overoptimistic expectations about the market. This suggests that, beyond slowing down matching, search frictions have a second understudied cost: they entrench inaccurate beliefs, further distorting search strategies and labour-market outcomes.