What’s the minimum sample size for pay gap reporting, and what if we don’t meet it?

The EU Pay Transparency Directive doesn’t set a hard minimum group size for pay reporting. But the general principle is clear: avoid reporting on groups so small that individual employees could be identified. If a group is too small, aggregate it with others or apply privacy protections.

There’s no single EU-wide rule for minimum group size. Instead, employers are expected to apply good judgment and align with broader data protection principles (such as GDPR).

Common guidance includes:

• Avoid publishing data for groups with fewer than 3–5 people.
• Aggregate small groups into broader job families or categories.
• Use anonymisation techniques (e.g. masking figures).

When employees request pay comparisons:

Even if formal reporting isn’t possible for small groups, employees may still ask for average pay levels. In those cases, employers should:

• Share aggregated averages, never individual salaries.
• Be transparent about why some data is withheld.
• Explain how pay relates to established salary bands.

Other considerations:

• Small samples can distort results, making gaps look bigger or smaller than they really are
• Rolling averages or multi-year comparisons can help smooth spikes
• Don’t rely on employee “consent” to share pay data. Under EU law, consent in employer–employee relationships isn’t considered valid.

To manage small group data, employers should:

• Define clear minimum thresholds for reporting.
• Build aggregation and anonymisation techniques into reporting systems.
• Prepare managers to explain why some information can’t be shared, without undermining employee trust.

See also: Which employees are included in the scope of the Directive? 

Protecting privacy while being transparent is a delicate balance. Handling small groups carefully keeps reporting credible and compliant, without exposing individual pay data.

Done right, this reassures employees that pay transparency is about fairness, not exposure.