Behavioural Insights in Action: Improving Tax Compliance Through Behaviourally Informed Training

Abstract This study examines whether behaviourally informed training can improve the effectiveness of phone-based tax debt collection in a public-sector setting. In collaboration with the Bulgarian National Revenue Agency, we implemented a two-day training programme for call centre agents focused on persuasion, negotiation and behavioural influence techniques derived from behavioural science and nudge theory. The impact of the intervention is assessed using descriptive comparisons of monthly aggregated debt-collection performance indicators before and after the training. We find that, following the intervention, trained agents achieved markedly better outcomes relative to pre-intervention periods, including an increase of approximately 20% in the total amount of debt collected over the subsequent three months and a higher rate of secured payment agreements. Notably, these improvements contrast with historical seasonal patterns that typically show a decline in collections during the same period. While the analysis is descriptive and does not permit definitive causal inference, the results provide strong indicative evidence that targeted behavioural training can enhance compliance outcomes in live, interpersonal interactions. The study contributes to the behavioural public policy and persuasion literatures by extending behavioural insights beyond written or digital nudges to real-time, conversational settings. From a practical perspective, the findings highlight the potential value of soft-skills and behavioural training for frontline public servants as a scalable and cost-effective tool for improving tax administration performance.