WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT • Attitude is an important factor impacting pharmacists' reporting of adverse drug events (ADE) to pharmacovigilance centres. • However, little is known about United States (US) pharmacists' attitudes with respect to ADE reporting. No known study has assessed US pharmacists' attitude to report serious ADEs to the FDA. WHAT THIS STUDY ADDS • This study results suggest that pharmacists hold favourable attitudes toward reporting serious ADEs to the FDA and there is an association between pharmacists' attitude and intention to report serious ADEs. • Pharmacists' beliefs that reporting serious ADEs was time consuming and disrupted the normal workflow impact on reporting intentions. • Pharmacists' attitudes towards reporting need to be improved in order to enhance patient and drug safety. AIM To investigate the influence of pharmacists' attitudes on intention to report serious adverse drug events (ADEs) to the Food and Drug Administration (FDA). METHODS This cross-sectional study used a mail survey to collect data from hospital and community pharmacists practicing in Texas, United States. Three and 16 items were used to measure intention and attitudes, respectively, using a seven-point bipolar scale. Pharmacists' demographic and practice characteristics, and past reporting were also measured. RESULTS The response rate was 26.4% (n= 377/1500 pharmacists). Most pharmacists intended (n= 297, 78.8%) to report serious ADEs that they will encounter to the FDA through MedWatch. Overall, pharmacists held favourable attitudes towards reporting serious ADEs (mean = 24.5, SD = 6.7, possible range 1–49, neutral = 16). Pharmacists intending to report serious ADEs had more favourable attitudes than those who did not (P < 0.001). About 90% of the pharmacists believed that reporting serious ADEs would improve patient safety. However, 72.6% indicated that reporting serious ADEs was time consuming and over half (55.5%) of the respondents believed that reporting serious ADEs disrupted the normal workflow. Non-intenders held stronger beliefs that ADE reporting would disrupt the normal workflow and was time consuming compared with intenders. Years of experience, number of hours worked and practice setting were associated with pharmacists' attitudes towards reporting (P < 0.05). CONCLUSIONS Most pharmacists held moderately favourable attitudes and high intentions toward reporting serious ADEs to the FDA. This study's findings contribute to an increased understanding of individual factors that influence pharmacists' attitude and intention towards reporting serious ADEs to the FDA.