Suppose you think of auditors’ work as completing a puzzle. Auditors can’t form a complete picture to conclude that the financial statements are “free from material misstatement” when evidence is missing or incorrect.

Audit evidence, then, is the information the auditors rely on to form a sound judgment.

But not all evidence is created equal. The standards emphasize two key qualities. First, the evidence must be appropriate, meaning it must be both relevant and reliable. Evidence must also be sufficient, referring to the quantity of evidence considered enough to convincingly support the auditor’s opinion.

While audit standards state that evidence must be “sufficient and appropriate,” in practice, those standards rarely specify precisely how much evidence is enough.

Drawing on interviews with 45 auditors from firms of varying sizes, we analyzed how professionals determine that they have collected sufficient appropriate evidence to conclude.

We found that auditors typically begin with established guidance: predefined document lists, criteria, and clear sampling and testing thresholds. These structured tools offer initial certainty, but they often fall short in complex or ambiguous situations, where risk, estimation, or unusual transactions challenge expectations. In such cases, auditors described a shift from checklist-based reasoning to a more adaptive, fluid process of interpreting and contextualizing evidence.

A central finding is that comfort drives many sufficiency decisions. Comfort reflects a provisional state that emerges through iterative judgment. When discomfort arises, auditors adjust expectations by revising thresholds, gathering incremental evidence, or forming new mental models. They also draw on prior experience, client history, and peer consultation to recalibrate what counts as enough evidence.

This suggests that evidence sufficiency is not a one-time determination, but a recursive feedback loop between structured procedures, interpersonal interactions, and auditors’ affective sense of when evidence sufficiency has been achieved. In practice, the process is shaped by interpersonal interactions as much as technical standards: discussions with clients, specialists, and reviewers often tip the balance toward either “we’re good” or “we need to keep going.”

Overall, the study contributes to a more realistic understanding of how sufficiency judgments are made. By uncovering how auditors blend procedural rules with evolving discomfort/comfort cues, our findings offer insights for standard setters, regulators, and practitioners seeking clearer guidance on evidence expectations, especially in complex areas involving estimates and uncertainty.

The reference for this article can be found below:

Altiero, E. C., Baudot, L., & Hazgui, M. (2025). ‘Are we good? or do we need to keep going?’: unraveling auditors’ comfort with evidence sufficiency determinations. European Accounting Review, 1–27. https://doi.org/10.1080/09638180.2025.2589183