Chief Sustainability Officer Role Shrinks 10% as New Appointments Dry Up

The chief sustainability officer role is contracting across US public companies for the first time after years of growth, with the total headcount falling 10% to 193 as of 1 July, according to Trellis. The driver is not a wave of departures but something quieter and, arguably, more telling: companies are simply not replacing CSOs when they leave.

The figures come from the latest annual CSO report by sustainability recruiter Weinreb Group, which has tracked the position across US-based public companies for over a decade. Headcount stood at 216 in 2025. The fall to 193 marks the first decline after consecutive years of growth. The rate of CSOs leaving their posts has remained relatively stable; what has shifted is the rate at which the role is being filled once vacated.

In other words, the question is not whether companies are pushing out their sustainability leads. The question is whether they see enough strategic value in the position to keep it at all.

Fewer CSOs Reporting to the CEO, the Organisational Signal That Matters

The headline number is one thing. The structural shift beneath it is another. Since January 2025, the proportion of CSOs reporting directly to the CEO has fallen from 33% to 14%, according to the Weinreb Group report. That is a collapse in seniority, not a marginal adjustment. When sustainability functions are pushed further from the boardroom, the capacity to influence capital allocation, supply chain decisions and Scope 3 strategy diminishes accordingly.

This matters for anyone trying to assess whether a company’s net-zero commitments carry organisational weight or exist primarily in a PDF. A CSO with a dotted line to a divisional head is not the same as one with a seat at the executive table. Science-based targets require cross-functional authority to land. Reporting obligations under frameworks such as TCFD and the emerging mandatory climate disclosure rules require someone with real internal leverage. A sustainability function buried two layers down from the CEO has less of both.

Some of those departing the CSO role have not left corporate sustainability entirely. In May, Tara Hemmer moved from the CSO position to the chief operating officer role at environmental services firm WM. Whether that represents a promotion of sustainability thinking into operational leadership, or simply the end of a dedicated sustainability function, is the kind of distinction that deserves scrutiny on a case-by-case basis.

The Chief Sustainability Officer Role in Long-Run Context

It would be wrong to read the current dip as a straightforward reversal of corporate sustainability commitment. Fifteen years ago, the role barely existed as a formal position: Weinreb Group recorded just 29 CSOs across US public companies in 2011. The current figure of 193, even after a 10% fall, is still a multiple of that baseline. The institutionalisation of sustainability as a board-level concern is not being undone by one year of flat hiring.

What the numbers do suggest is that the role is maturing and, in some cases, being absorbed. Sustainability considerations are increasingly embedded in finance, legal, procurement and operations functions rather than sitting in a standalone office. That integration can be a genuine sign of mainstreaming. It can also be a way of diffusing accountability without replacing it, and of making ESG commitments harder to track from the outside.

The Weinreb Group data does not resolve which dynamic is dominant. What it does confirm is that the pipeline of new CSO appointments has thinned sharply, and that the seniority of those still in post has declined. For sustainability professionals evaluating whether to pursue or retain a CSO-level position, and for ESG analysts trying to read organisational commitment from corporate structure, those are the two figures worth watching.

The full Weinreb Group CSO report, covering appointments, tenure, reporting lines and sector breakdowns, is available for further context. Edie has covered the longer-run trajectory of the role alongside the current year’s data.