PurposeThis study analyses the way various components of intellectual capital (IC), namely, human capital (HC), structural capital (SC), relational capital (RC) and innovation capital (INNC), act as mediators in the relationship between managerial ability (MA) and a firm’s ability to achieve growth.Design/methodology/approachThis study employs data envelopment analysis to quantify the MA of 825 Taiwanese listed electronics companies from 2017 to 2022. The proxies of firm growth are return on asset growth, operating income growth and total asset growth. This study then utilises a three-step mediation analysis methodology to examine the relationships between MA, IC and firm growth.FindingsFindings indicate that HC, SC, RC and INNC mediate the link between MA and firm growth. This suggests that competent managers can capitalise on the potential benefits of these investments to achieve firm growth.Practical implicationsCompetent managers can utilise different IC investments to grow the financial performance and strength of their businesses. Managers should continually scan, secure opportunities and adjust their investments in knowledge assets in accordance with the dynamic capabilities view. That is, managers, in general, and operations managers, in particular, can implement guidelines that prioritise IC investments in the future to expedite firms’ development.Originality/valueThis study extends the existing frameworks that study investment variables as mediators between MA and firm outcomes. Most particularly, this study adopts four components of IC for measurement. Moreover, firm performance is measured using dynamic growth indicators rather than static measures.