The paper investigates the value of AACSB accreditation for business schools. The status of an accredited school decreases the asymmetry of information and the study aims to fill the gap if this market signal has a value beyond enhancing the quality itself. It is based on the international panel data of the AACSB Business Schools Questionnaire and shows that, on average, business schools demonstrate a higher economic performance after the accreditation is received. The results contribute to the signalling theory hypothesis that quality enhances the ability to observe the signal by the market. The positive effect of AACSB accreditation is heterogeneous and stronger for MBA programmes. In addition, we discovered that the effect lags in time and the market fully observes it at least one enrolment cycle later. The results provide an international perspective of the effects that AACSB accreditation has on the performance of business schools and is relevant both for academics and education policymakers.