Bonus gap — the differential that rarely appears in the annual report

When companies prepare to discuss pay equity, the conversation almost always opens with the base salary gap. The base gap is what published statistics report, what national authorities benchmark, and what the typical HR Director can produce from payroll without much friction.

The bonus gap — the differential in complementary or variable pay components — is rarely volunteered. Not because it is hidden, but because it is less observable in the workflows companies already run. The directive requires it anyway.

Two gaps, one report

The directive treats variable pay as a separate reporting axis precisely because the two gaps move differently. A company can have a clean base gap and a substantial bonus gap. The base gap reflects what the company pays for the role on paper; the bonus gap reflects what the company pays for the role in practice.

Why the bonus gap is often the bigger number

Variable pay structurally amplifies underlying patterns in two ways.

First, eligibility is non-uniform. Not every employee receives a bonus. Roles in some functions — sales, executive, finance — have variable pay; others rarely do. Where women are over-represented in functions without bonus structures, the proportion-receiving metric (Article 9, items 05 and 06) surfaces a participation gap before any pay-amount gap is calculated.

Second, when eligible, the amounts vary more. Base salaries cluster around a defined band. Bonuses can be 0% or 30% of base depending on individual performance, target achievement, or discretionary allocation. The wider the variability, the more room for systematic patterns to develop.

The compounding is mechanical: a 5% base gap plus a 15% bonus gap, with variable pay at 20% of total compensation, produces a total-compensation gap of about 7% — meaningfully larger than the base gap alone. Over a five-year horizon, the differential propagates into pension accruals, severance calculations, and offers extended at re-entry to the labour market.

A worked example

Two employees in the same category of work, both at the company for three years. Same base salary band: €70k. Both eligible for an annual performance bonus targeted at 20% of base, achieved at company discretion based on individual performance and team contribution.

The reported base gap is 0%. The bonus gap, by Article 9 metric 03, is roughly 27%. The total compensation difference over three years is €12,000 — meaningful, and not visible in the base-only conversation.

What Article 9 actually requires for variable pay

Article 9, paragraph 1, lists three variable-pay metrics among the nine total. Reading them in sequence:

1. Mean gender pay gap in complementary or variable components. Calculated across all employees who receive any variable pay, by sex.
2. Median gender pay gap in complementary or variable components. Same population, the middle value.
3. Proportion of female and male workers receiving complementary or variable components. The eligibility-and-receipt rate, by sex.

The third metric is the one most easily overlooked. It is not asking "how much do recipients receive?"; it is asking "who is among the recipients at all?" A company where 80% of men but only 50% of women receive any variable pay has a structural pattern that the amount-based metrics may not surface.

Article 8 — the right-to-information angle

Article 8 of the directive (Information on gender pay gap) interacts with the reporting requirement in Article 9. Under Article 7, individual employees have the right to receive comparator information on their pay level — and "pay" includes variable pay. An employee comparing themselves to a colleague will compare not just base salary but also total compensation, including bonus.

An employer that has documented the bonus gap and the rationale for it is positioned to answer an Article 7 request defensibly. An employer that has measured only the base gap, having never run the bonus calculation, is answering with incomplete information.

How to calculate the bonus gap defensibly

Three definitional choices determine whether the calculation is reproducible:

Which payment cycle. The reference period is the calendar year preceding submission. All variable payments made during that year are in scope: annual bonuses, quarterly bonuses, retention payments, signing bonuses (if applicable to the period), commissions, allowances, equity awards (typically at vesting value).

Annualisation and FTE normalisation. Part-time employees and partial-year tenured employees require normalisation. A common approach: annualise to full-time equivalent. Document the method; apply consistently across sexes.

The population. Metrics 03 and 04 (mean/median bonus gap) are calculated only on recipients. Metrics 05 and 06 (proportion receiving) are calculated on the full eligible population. Mixing these populations produces incorrect numbers.

The base gap is what the report shows. The bonus gap is what the report makes visible that the company hadn't measured.

Where the diagnostic starts

Calculating the bonus gap requires a payroll export that breaks out variable components, an FTE/period normalisation methodology, and a defined category structure to compute the per-category figures Article 9 requires. The methodology must be documented before it is applied.

The ReadinessCheck™ surfaces whether the prerequisite documentation is in place — by axis of the directive's principal obligations. It does not calculate the bonus gap. It tells you whether the company can.