PurposeThis paper investigates the challenges and opportunities for the deployment of whistleblowing as an accountability mechanism to curb corruption and fraud in a developing country. Nigeria is the institutional setting for the study.Design/methodology/approachAdopting an institutional theory perspective and a survey protocol of urban residents in the country, the study presents evidence on the whistleblowing program introduced in 2016. Nigeria’s whistleblowing initiative targets all types of corruption, including corporate fraud.FindingsThis study finds that, even in the context of a developing country, whistleblowing is supported as an accountability mechanism, but the intervention lacks awareness, presents a high risk to whistleblowers and regulators, including the risk of physical elimination, and is fraught with institutional and operational challenges. In effect, awareness of whistleblowing laws, operational challenges and an institutional environment conducive to venality undermine the efficacy of whistleblowing in Nigeria.Originality/valueThe study presents a model of challenges and opportunities for whistleblowing in a developing democracy. The authors argue that the existence of a weak and complex institutional environment and the failure of program institutionalization explain those challenges and opportunities. The authors also argue that a culturally anchored and institutionalized whistleblowing program encourages positive civic behavior by incentivizing citizens to act as custodians of their resources, and it gives voice to the voiceless who have endured decades of severe hardship and loss of dignity due to corruption.