Earlier this year, ISEAL and IDH published two new guidance documents to help companies and verification providers turn living wage-gap data into reliable evidence for meaningful action.

At the IDH Living Wage & Living Income Summit in Rotterdam on 30 June, ISEAL joined over 500 participants to reflect on the importance of living wages and the steps needed to ensure living wage efforts lead to real-world impact. The Summit discussions reflected how the conversation has shifted: from making the case for living wages and measuring wage gaps, to understanding how companies can act on findings and show credible progress.

The scale of the challenge is clear. One in three workers does not earn a decent wage yet corporate commitment remains strikingly low. An important first step is understanding the living wage gap: the difference between workers’ current remuneration and a credible living wage estimate. Closing that gap requires action, but it also requires reliable information that companies, suppliers and sustainability standards can trust to identify the most appropriate response and assess progress over time.

The need for reliable evidence was a recurring theme at the Summit, and it is where ISEAL and IDH’s new guidance on credible living wage verification can help. One supports verification providers with good practice for validating living wage gaps. The other helps companies understand what credible verification involves so they can commission verification services, assess providers and evaluate the findings they produce. Together, they provide a shared framework for more consistent, credible and practical verification across different sectors and supply-chain contexts.

What makes living wage verification credible?

Living wage gap verification provides independent assurance that a previously calculated gap is accurate and reliable. It is not simply a check that payroll records exist or that legal minimum wages are being paid. As the Summit discussions highlighted, measurement and verification are not only technical exercises; they also require trust among companies, suppliers, workers and other organisations involved. Credible verification requires transparency about gaps and honesty about what the numbers show.

The guidance centres three questions. First, what is being verified? Wage data, in-kind benefits and calculation assumptions need to be traceable and suitable for comparison with a living wage estimate. Second, how is the information being verified? Robust practice typically includes systematic procedures, triangulation, risk-informed sampling, worker interviews and transparent documentation of methods, assumptions and limitations. Third, who is doing the verification? Providers need the right technical competence, independence and impartiality to reach defensible conclusions.

These requirements distinguish living wage verification from a standard audit. Validating wages and in-kind benefits in informal sectors, piece-rate payment arrangements, or other complex forms of remuneration call for specific technical checks that go beyond confirming compliance with legal minimum wages. Though verification can be integrated into existing certifications or audit processes, it should not be reduced to one extra checklist question. Additional technical checks and technically qualified auditors or verification personnel are essential.

From reliable evidence to credible claims

As expectations around sustainability claims, human rights due diligence and progress reporting grow, companies need wage-related information that is accurate and traceable. The company guidance explains the evidence needed to support credible reporting and claims related to living wage gaps. Practitioners at the Summit also reinforced that reporting should support ongoing accountability and learning, helping organisations improve decisions and refine their approach rather than simply communicate results.

Verification is an important step, not the end goal. It can help companies, suppliers and sustainability systems understand the scale and distribution of wage gaps and investigate their underlying causes. Closing wage gaps still depends on wider conditions including social dialogue, supplier engagement, and coordinated action and alignment across the supply chain.

For suppliers and producers or manufacturers, stronger verification can bring practical benefits such as better wage management and payroll systems, stronger commercial relationships and clearer evidence of responsible business performance. Those benefits increase when buyers also acknowledge their role by adapting purchasing practices and helping to meet implementation costs.

One of the Summit’s clearest messages was that organisations do not make progress by waiting for perfect clarity. They take the next step, learn and adapt. Credible living wage verification is a vital part of that process. Measurement should not be an end in itself. It should generate reliable evidence that supports better-informed decisions and sustained action to close living wage gaps.

To learn more, explore ISEAL’s resources on living wage and read IDH’s article for an overview of key issues discussed at the Summit.