PurposeThis research employs a behavioural approach to investigate the determinants of CEO disclosure tone inconsistency. By examining CEO characteristics and psychological attributes, the study aims to unravel the complexities underlying tone variations in Management Discussion and Analysis (MD&A) reports. Through this exploration, the research seeks to contribute to understanding ethical considerations in corporate communications and provide insights into the nuanced interplay between personal, job-related and psychological factors influencing CEO disclosure tone.Design/methodology/approachThe study utilises a dataset comprising 1,411 MD&A reports from 143 companies listed on the Tehran Stock Exchange between 2012 and 2021. Multiple regression analyses with year- and industry-fixed effects are employed to examine the relationships between CEO gender, tenure, duality, ability and psychological attributes such as narcissism, myopia, overconfidence and tone inconsistency. Data analysis involves MAXQDA software for analysing MD&A reports and Rahavard Novin software for document analysis, supplemented by audited financial statements.FindingsThe findings reveal significant relationships between CEO characteristics, psychological attributes and tone inconsistency. Female CEOs exhibit reduced tone inconsistency, contrasting with previous research trends. CEO tenure correlates negatively with tone inconsistency, whereas CEO ability shows a positive correlation, indicating a nuanced relationship with performance. However, CEO duality does not exhibit a significant association. Psychological attributes such as narcissism and myopia are positively associated with tone inconsistency, while no substantial connection is found with managerial overconfidence.Originality/valueThis research contributes to the inaugural exploration of CEO disclosure tone inconsistency through a behavioural lens, advancing measurement precision in the field. By delving into CEO characteristics and psychological attributes, the study offers unique insights into the roots of tone inconsistency. Applying comprehensive lexicon and phraseology enriches the methodological approach, fostering dialogue among diverse stakeholders and adding distinct perspectives to the discourse on ethical issues in business. Through its meticulous examination of behavioural underpinnings, this study becomes a catalyst for reflection, dialogue and progress in corporate communications and ethical considerations.