60 Years of Equal Pay Law. What Each Milestone Changes in Your Compensation System.

This is not a new problem. It is a new obligation to disclose it. In this series, we trace sixty years  of legislation that gradually expanded the definition of equal pay. From prohibiting discrimination within the same workplace to mandatory reporting across the entire organisation. Each of the five acts changed something  specific: what can be measured, who bears the burden of proof, what counts as pay at all. Together they form a map without which it is hard to design a pay structure compliant with Directive 2023/970. The Mind the Pay Gap: World Tour setlist is not decoration. It is sixty years of law — and five moments that changed the rules of compensation. Next stop: your company, 2027.

Five acts, Five Definitions of Equality

Each law addressed a specific gap in the previous one. Together theybuild the logic now reflected in Directive 2023/970. For C&B, this is the requirementsarchitecture you will work with for years to come.

Act I — United States, 1963. Equal pay for the same work — the first threshold.The Equal Pay Act prohibited pay differentiation based on sex for "substantially equal work" within the same establishment. It was a breakthrough, but with a built-in limitation: it covered only one axis of comparison and only workers in the same workplace. Women discriminated against for multiple reasons at once remained invisible to the law. A key concept emerges: "substantially equal work" — the foundation for later definitions of job categories and job evaluation. Today this translates into the obligation to compare pay across job groups, not just identical job titles.

Act II — United Kingdom, 1970. The Ford strike and the maternity penalty.
The Equal Pay Act in the UK was forced through by the grassroots strike of 187 seamstresses at Ford's Dagenham plant. The issue: classification of their work as skilled labour. The Act equalised pay for the same work — but did not close the gap, because its silent driver turned out to be maternity. Pay differences are often not direct discrimination — they are the cumulative effect of pay decisions made over years. Pay gap analysis must account for tenure, promotion history, and variable pay components, not just base salary.

Act III — European Union, 1975. Work of equal value — the change that struck at the root.
Directive 75/117/EEC replaced the criterion of "the same work" with "work of equal value." This was a fundamental shift: for the first time the law recognised the systemic undervaluation of entire occupations dominated by women. This is the origin of the job evaluation requirement in Directive 2023/970. C&B must build a methodology based on 4 criteria (skills, effort, responsibility, working  conditions) that is gender-neutral and defensible in a joint pay assessment.

Act IV — European Union, 2006. The burden of proof shifts to the employer.
Directive 2006/54/EC (Recast  Directive) consolidated existing legislation and shifted the burden of proof. The employer must demonstrate that a pay difference does not result from discrimination. The law no longer requires proof of intent. Every unjustified pay difference is a potential legal risk — regardless of intent. Documentation of pay differentiation criteria is no longer optional. It is now the foundation of any defence in a joint pay assessment.

Act V — European Union, 2023. Transparency as a tool — and as a requirement.
Directive 2023/970 does not create a new right to equal pay. That right has existed since 1957. It creates a transparency obligation. Pay ranges in job postings, the right of workers to pay information, pay gap reporting by quartile — every company with 250+ employees must implement this by 2027. This is the moment when Comp &  Ben becomes a strategic function. Pay data previously kept internal will be disclosed. Time for a pay structure audit. The right to equal pay never waited for a convenient political moment. The 2023 Directive is not waiting either. Deadline for 250+ companies: June 2027.

Why we're telling this story now

Directive 2023/970 has a transposition deadline: 7 June 2026. The first mandatory pay gapreports for organisations employing 250 or more workers will be required fromJune 2027 (under the Directive). This is not an abstraction — it is a date inthe Comp & Ben team's calendar. In thearticles that follow, we unpack each legislative act separately: with data, research, and specific implications for pay structure. At the end of theseries: a practical action map for Comp & Ben covering 2026–2027. Your pay gap already exists. The question is: Who will find it first? An auditor, a job candidate, or anemployment tribunal.

This article is part of the Mind the Pay Gap: WorldTour series — Levelly.ai's educational campaign dedicated to Directive 2023/970and compensation strategy aligned with the principle of equal pay.

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