Pay equity lawsuits are expensive to defend, difficult to win once discovered, and create lasting reputational damage with both current employees and prospective candidates. Voluntary pay equity analysis and systematic remediation is always cheaper than litigation — and increasingly, it is required by law rather than optional best practice. Understanding how to conduct a rigorous analysis and what to do with the results is now a core competency for HR Directors in both the UK and US.
What Pay Equity Analysis Is and Why It Matters Now
Pay equity analysis is the systematic examination of compensation across an organisation to identify whether employees in comparable roles are paid differently based on characteristics that should be legally irrelevant to compensation — typically gender, race, ethnicity, age, or disability status.
The reason pay equity has accelerated from a compliance checkbox to a strategic priority is threefold. First, legislative momentum is building: the UK's mandatory Gender Pay Gap Reporting requirement applies to all organisations with 250 or more employees, pay transparency laws are advancing across US states (Colorado, California, New York, Illinois, and others now require salary ranges in job postings), and the EU Pay Transparency Directive will require member states to mandate pay equity reporting by 2026. Second, enforcement is increasing — EEOC pay discrimination charges are rising annually, and UK Employment Tribunal claims related to equal pay have increased significantly. Third, candidate and employee expectations have changed — pay transparency and equity are now active factors in employer brand perception and talent attraction.
For HR Directors, this means pay equity analysis is no longer a task to be delegated to a consultant every three years. It needs to be a regular, data-driven process embedded in compensation planning cycles.
The Business Case Beyond Compliance
McKinsey's research consistently finds that gender-diverse companies outperform their peers by 15–25% on profitability metrics. Pay equity is both a direct gender diversity issue and an indicator of broader compensation management quality. Companies with systematic pay equity practices report lower voluntary turnover, higher employee engagement scores, and better performance review calibration — all of which have measurable P&L impact beyond compliance risk reduction.
The Difference Between Unadjusted and Adjusted Pay Gaps
One of the most important distinctions in pay equity analysis is between the unadjusted (raw) gap and the adjusted (controlled) gap. Understanding this distinction is critical for correctly interpreting analysis results and communicating them to leadership.
The unadjusted gap compares average pay across demographic groups without controlling for any other variables. For example, if women in your organisation earn on average 15% less than men, that is the unadjusted gap. This number is important and legally significant — it reflects actual earnings differences — but it does not reveal their cause. The gap may be driven by occupational segregation (women are concentrated in lower-paying roles), seniority differences, part-time vs full-time split, or genuine pay discrimination within comparable roles.
The adjusted gap controls for job-relevant variables — role, level, tenure, performance rating, location — to compare pay between employees who are genuinely similarly situated. If women in your engineering team at the same level and tenure as their male peers earn 4% less, that adjusted gap is unexplained by legitimate compensation factors and requires investigation and remediation.
UK Gender Pay Gap Reporting requires disclosure of the unadjusted gap. But effective pay equity management requires both: the unadjusted gap identifies where to look, and the adjusted gap identifies where discrimination risk actually lies.
How to Run a Pay Equity Analysis: Step by Step
A rigorous pay equity analysis follows a structured methodology. Here is the standard approach used by compensation consultants and HR analytics functions:
- Define the comparison groups: Identify which employees are genuinely comparable for compensation purposes. This typically means grouping employees by job family, level/grade, and work location — not by job title, which varies too much across organisations to be analytically reliable.
- Collect compensation data: Gather base salary, total cash compensation (including bonus and commission), and relevant benefits that have economic value. For equity awards in listed companies, include fair value estimates. Ensure you have data for the same point in time across all employees.
- Run the regression analysis: Use a multiple regression model with compensation as the dependent variable and job family, level, tenure, performance rating, and location as control variables. The demographic variables (gender, race/ethnicity) are added last. Statistically significant coefficients on demographic variables after controlling for all legitimate factors indicate a pay equity issue.
- Identify the affected population: Quantify both the number of employees with statistically significant pay gaps and the aggregate remediation cost. Most organisations find that 3–8% of their workforce has an unexplained adjusted gap requiring attention.
- Validate the findings: Cross-check statistical outliers against individual employee records. Some adjusted gaps are explained by factors not captured in the model — recent promotion timing, performance trajectory, or unique role characteristics. Document the cases where adjusted gaps are legitimate and the cases requiring remediation.
- Design the remediation plan: Prioritise remediation by gap magnitude and statistical significance. Not all gaps can be closed in one compensation cycle. Create a multi-year plan with annual progress tracking.
Pay Compression: The Hidden Equity Problem
Pay compression — where newer employees are hired at market rates that approach or exceed longer-tenured employees' salaries — creates an equity problem that is not demographic in origin but often intersects with demographic gaps. If women or ethnic minorities are disproportionately represented in the longer-tenured group affected by compression, pay compression amplifies a demographic gap. Treegarden's pay equity analytics include pay compression detection, flagging cases where hire-date pay rates are within 10% of longer-serving colleagues in the same role band.
What to Do When You Find a Gap
Discovering a statistically significant pay gap after controlling for legitimate factors creates both a legal obligation and a management challenge. The response must be structured, documented, and implemented consistently.
The first decision is whether to remediate immediately or in the next compensation cycle. Gaps above a threshold — typically 5% or more of affected employees' base salary — generally warrant immediate off-cycle adjustments. Smaller gaps can typically be addressed in the annual merit review without disrupting compensation cycle integrity.
When implementing remediation, raise the affected employees' compensation to eliminate the gap. Never lower other employees' pay to reduce a gap — this creates a separate legal and morale problem. Document the remediation clearly in each affected employee's compensation record with a note indicating it is an equity adjustment, not a merit increase. This distinction matters for future compensation decisions.
Importantly, equity adjustments should not be communicated to employees as corrections of past errors unless the organisation has a legal disclosure obligation. Instead, frame them as part of the company's compensation review process — accurate, respectful of the employees affected, and avoiding creation of litigation triggers for employees who may not have been aware of a discrepancy.
UK: Gender Pay Gap Reporting Requirements for 250+ Employees
UK employers with 250 or more employees must publish six specific metrics annually under the Equality Act 2010 (Gender Pay Gap Information) Regulations 2017:
- Mean gender pay gap in hourly pay
- Median gender pay gap in hourly pay
- Mean bonus pay gap
- Median bonus pay gap
- Proportion of men and women receiving bonus pay
- Proportion of men and women in each pay quartile
These figures must be published on the employer's website and on the government reporting service by 4 April each year (private sector) or 30 March (public sector). Narrative explanation is not mandatory but is strongly recommended — employers who publish only numbers without context face reputational risk if their figures are unfavourable compared to industry peers.
The UK reporting requirement is an unadjusted gap — it does not require employers to demonstrate that the gap is explained by legitimate factors. However, the public nature of the data means that employers with high gaps face scrutiny from media, employees, and prospective candidates, creating a strong incentive for voluntary adjusted analysis and remediation.
US: Pay Equity Laws by State
The US pay equity landscape is fragmented, with federal law (the Equal Pay Act 1963 and Title VII) providing a floor and state laws increasingly creating higher standards. Key developments for US HR Directors:
- Colorado (EPEWA 2021): Requires salary ranges in all job postings and imposes prohibition on pay discrimination based on sex and other protected classes. First state to mandate salary transparency in job postings.
- New York City (Local Law 32, 2022): Requires salary ranges in all job postings for NYC-based roles. Applies to employers with four or more employees.
- California (SB 1162, 2022): Requires pay scale disclosure in job postings and mandates annual pay data reporting to the California Civil Rights Division, including median and mean hourly rates by race, ethnicity, and sex for each job category.
- Illinois (Equal Pay Act amendments, 2021): Requires equal pay registration certificates for employers with 100+ employees, including demographic pay data reporting to the Illinois Department of Labor.
- Washington, Rhode Island, Nevada, Maryland, Connecticut: Additional states with salary disclosure requirements that took effect between 2021 and 2024.
For multi-state US employers, the most conservative compliance approach is to include salary ranges in all job postings regardless of state requirement, run annual pay equity analyses, and maintain documentation sufficient to respond to state civil rights department data requests.
| Feature | Treegarden Pay Equity Module | Manual Spreadsheet Analysis |
|---|---|---|
| Automated data aggregation | ✓ Pulls from employee records directly | Manual export and merge required |
| Gender pay gap calculation (UK) | ✓ Six statutory metrics generated | Manual formula construction |
| Pay compression detection | ✓ Automated flag at configurable threshold | Manual tenure vs salary comparison |
| Role band-level analysis | ✓ Group by level, family, location | Manual pivot table construction |
| Remediation cost modelling | ✓ Scenario modelling built-in | Manual spreadsheet modelling |
| Audit trail for remediation decisions | ✓ Documented per employee | Manual documentation required |
How Treegarden's Salary Analytics Runs Pay Equity Reports
Treegarden's compensation analytics module connects directly to employee salary records and role data, enabling pay equity reporting without manual data exports. The analysis is run from the HR analytics dashboard, where administrators select the analysis period, define the comparison variables (role family, level, tenure bracket, location), and select the demographic dimensions to analyse.
The output includes both unadjusted gaps (mean and median compensation by demographic group) and controlled analysis output organised by role band, making it straightforward to identify which groups and which role levels show statistically significant unexplained gaps. UK employers receive the six Gender Pay Gap Reporting statutory metrics directly from the report, formatted for submission to the government reporting service.
Pay compression detection runs alongside the equity analysis, flagging cases where newer employees in the same role band are paid within a configurable threshold (default: 10%) of longer-tenured colleagues. These cases are presented separately from demographic equity gaps, enabling HR Directors to manage both issues with appropriate remediation approaches in the annual compensation cycle.
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Frequently Asked Questions
What is the difference between gender pay gap and pay equity?
The gender pay gap is a measure of the average earnings difference between all men and all women in an organisation, regardless of role. It is an unadjusted, aggregate measure. Pay equity analysis compares pay within comparable roles, controlling for legitimate compensation factors, to identify whether employees doing equivalent work are paid differently based on protected characteristics. A company can have a significant gender pay gap driven by occupational segregation (more women in lower-paid roles) while achieving pay equity within each role band. Both require attention, but they reflect different problems with different solutions.
How often should a company run a pay equity analysis?
Annually is the standard recommendation, timed to coincide with the compensation review cycle so that equity findings can inform merit increase decisions. UK employers with 250+ employees must publish gender pay gap data annually, making annual analysis a compliance requirement. US employers in pay transparency states have reporting obligations that require at minimum annual data collection. Companies undergoing rapid growth, acquisitions, or significant hiring campaigns may benefit from mid-year spot checks.
Do we need to disclose the results of a pay equity analysis to employees?
UK employers with 250+ employees are legally required to publish Gender Pay Gap metrics publicly. US employers are generally not required to disclose pay equity analysis results to employees, though state laws vary. Sharing aggregate results (without individual data) with employees as part of a pay equity commitment communication is a best practice that builds trust — but legal counsel should review the communication to avoid creating document obligations in potential litigation.
What causes pay equity gaps after controlling for role and level?
The most common causes of unexplained adjusted pay gaps are: negotiation patterns at hire (men historically negotiate starting salaries more aggressively, creating a gap that compounds with merit increases), promotion timing differences, performance rating bias (research shows women and minorities receive lower performance ratings at equivalent performance levels), and manager discretion in merit increase allocation without central calibration. All of these require targeted intervention beyond simply adjusting compensation after the fact.
Is pay equity analysis protected from legal discovery?
In some circumstances, pay equity analyses conducted under attorney-client privilege may be protected from discovery in litigation. This depends on jurisdiction, the nature of the privilege claim, and how the analysis was conducted. HR Directors considering this protection should consult employment counsel before commissioning an analysis they wish to protect. Note that voluntarily disclosing the results of an analysis — even in general terms — may waive privilege protection in some jurisdictions.
Pay equity is no longer a compliance activity that HR Directors can delegate to a consultant every few years. Legislative momentum on both sides of the Atlantic, rising enforcement activity, and changing candidate and employee expectations mean that regular, rigorous pay equity analysis is now a baseline expectation for professional HR management. Treegarden's salary analytics module brings this capability in-house — with automated data aggregation, UK statutory metric generation, pay compression detection, and remediation modelling — at a cost point that makes it accessible to growing companies without enterprise HRIS budgets. Book a demo to see the pay equity module with your specific workforce data structure.