We integrate firm growth theory and the behavioural theory of the firm to examine TMTs’ responses to excess cash, identified as financial slack, within the context of Economic Policy Uncertainty (EPU) and its influence on firm performance. Utilizing a sample of companies listed on the Growth Enterprise Market in China spanning from 2012 to 2019, our findings indicate that financial slack is susceptible to appropriation, particularly by TMTs with longer or more diverse tenures, leading to compromised firm performance. EPU functions as a boundary condition, revealing that TMTs with longer tenures exhibit enhanced collaboration in securing cash during uncertain circumstances. However, our study also highlights that EPU does not mitigate the impact of TMT tenure heterogeneity on financial slack.