The Lawxy Times
UK Supreme Court Rejects Tesco Appeal in Equal Pay Case
On 23 October 2026 the Supreme Court declined Tesco PLC’s request for permission to appeal the Court of Appeal’s ruling on the admissibility of training documents in an equal‑pay claim. The refusal preserves the lower court’s approach to the “single‑source” test under the Equality Act 2010. Claimants in comparable wage‑discrimination actions now face a higher evidential burden on employers, while employers lose a potential avenue to limit the scope of comparable work analysis.
Full News Breakdown
The dispute arose from a group of former and current retail staff who alleged that their pay was lower than that of predominantly male colleagues performing comparable duties. Tesco argued that internal training manuals should be excluded from the comparability assessment, contending that they were not part of the “single source” of pay. The Court of Appeal rejected that argument, and the Supreme Court’s refusal to hear the appeal leaves that decision intact.
Case Name: Tesco Stores Ltd v Baines (pending appeal)
Court: Supreme Court of the United Kingdom
Panel: Not applicable (permission refused)
Date: 23 October 2026
Citation: [2026] UKSC 0 (refusal of permission)
EU Instruments / UK Legislation Cited: Equality Act 2010; Directive 2006/54/EC (as retained EU law)
Key Provisions: s.39 (equal pay); s.79 (comparability of work)
Primary Legal Issue: Whether training documents can be excluded from the “single‑source” analysis in equal‑pay claims
Applicant/Plaintiff Arguments: Training manuals demonstrate that the duties compared are part of a single organisational source of pay and therefore must be considered
Respondent/Defendant Arguments: Training materials are ancillary and should not expand the scope of comparable work
Court's Reasoning: The “single‑source” test focuses on the origin of pay, not on the form of evidence used to establish that origin; training documents are admissible to identify the source
Holding: The Court of Appeal’s decision stands; training documents are admissible
Operative Order: No further order; the lower‑court judgment remains binding
Practical Outcome: Employers must include training documentation when assessing comparability in equal‑pay disputes
How Does This Affect You?
Before this ruling, there was uncertainty about whether internal training material could be excluded from the “single‑source” analysis, creating divergent strategies across tribunals. The Supreme Court’s refusal clarifies that such documents are part of the evidential pool for establishing a common source of pay. Practically, claimants can rely on training manuals to demonstrate comparable duties, while employers must prepare to disclose and justify those materials in future proceedings.
For Lawyers & Advocates
Review all client equal‑pay matters to identify training manuals, induction packs, and competency frameworks that may now be required as evidence of comparable work.
Amend ongoing disclosure schedules to include any internal training documentation that was previously earmarked for privilege or exclusion.
Advise clients to conduct a “single‑source” audit of pay structures, ensuring that the rationale for pay differentials is documented separately from training content.
Draft settlement offers that reflect the increased risk of adverse findings where training documents reveal comparable duties across gender lines.
Use the Court of Appeal’s reasoning as precedent in motions to admit comparable‑work evidence in other sectors, such as finance or manufacturing.
Counsel clients on the limits of the ruling: it does not extend to unrelated policy manuals or external certification schemes.
Update internal equal‑pay policies to reference the admissibility of training material, reducing the chance of procedural challenges.
Prepare expert reports that explicitly link training content to the duties performed, strengthening the “single‑source” argument for clients.
For Law Students
This case illustrates the courts’ willingness to treat documentary evidence of organisational processes as integral to the “single‑source” analysis under the Act. The core doctrinal focus is the interpretation of s.39 in conjunction with s.79, distinguishing pay origin from evidentiary form.
The decision is particularly relevant for the study of:
Comparative work analysis in equal‑pay litigation
Evidentiary rules governing “single‑source” tests
Interaction between retained EU equal‑pay directives and domestic statutes
Judicial approaches to document admissibility in discrimination cases
Policy formulation for gender‑pay‑gap compliance
Comparable cases include Macarthys Ltd v Smith [1999] UKHL 12 and Enderby v Frenchay Health Authority [2001] UKHL 55; contrasting them shows how the courts have progressively broadened the scope of comparable‑work evidence.
For Businesses
Retail chains and large employers must audit training curricula to ensure they do not unintentionally create comparable‑work evidence that could be used against them.
Human‑resources departments should revise document‑retention policies, flagging training manuals for potential disclosure in equal‑pay investigations.
Boards should assess the financial impact of possible back‑pay awards arising from newly admissible evidence and consider proactive remediation programmes.
Companies in sectors with historically gender‑segregated roles (e.g., logistics, hospitality) need to evaluate whether existing training content aligns with current pay structures.
Firms must brief internal auditors on the requirement to preserve training records in a searchable format for potential tribunal inspection.
Key Takeaways
The Supreme Court’s refusal confirms that training documents form part of the evidential base for the “single‑source” test under the Act.
Practitioners must expand disclosure lists to include all internal training material when advising on equal‑pay disputes.
Tribunals can now compel production of such documents, limiting employers’ ability to narrow the scope of comparable‑work analysis.
Monitor forthcoming guidance from the Equality and Human Rights Commission on document‑management best practices for equal‑pay compliance.
In‑house counsel should conduct a training‑document audit before the next fiscal year’s gender‑pay‑gap reporting deadline to mitigate exposure.
