AimTo explore how undergraduate nursing students are assessed on nursing numeracy and medication calculations from the perspective of Australian nurse education leaders.DesignA qualitative study.MethodsSemi‐structured interviews were conducted with 17 nurse education leaders between November 2022 and January 2023. Braun and Clarke's six phases of thematic analysis were used to analyse the data.ResultsFive key themes were identified: (i) high expectations to keep the public safe, (ii) diverse assessment formats, (iii) different ways of managing assessment integrity, (iv) assessment conditions incongruent to the clinical setting and (v) supporting struggling students.ConclusionNurse education leaders set high standards requiring students to achieve 100% in numeracy and medication calculation assessments, thus maintaining the reputation of nursing and patient safety. However, students struggled to meet this expectation. Diverse assessment formats were implemented, with some examination conditions contrary to clinical practice. Currently, there is no benchmark or independent point of registration examination in Australia, hence the problem is each university had a different standard to judge students' competence. Gaining insight into how these assessments are conducted provides an opportunity to work towards an evidence‐based model or benchmark for the assessment of numeracy.Implications for the ProfessionDosage errors in clinical practice threaten patient safety and the reputation of the nursing profession. The accuracy rate of calculations by undergraduate and registered nurses is deficient worldwide. This research highlights a major educational issue, that being the wide variation in how numeracy assessments are conducted with no clear pedagogical rationale for a standardised method. Such assessments would establish a national standard, contributing to quality assurance, the development of the nursing profession and improve patient safety.