UK moves ahead with voluntary oversight regime for sustainability assurance

Following the Government’s consultation on developing an oversight regime for assurance of sustainability-related financial disclosures (see our article on the Government's consultation), the UK Government has confirmed it will establish a voluntary, regulator backed oversight regime for sustainability assurance providers, operated by the Financial Reporting Council (FRC). 

What is the aim of the oversight regime?

The aim of the oversight regime is to build trust in sustainability-related financial disclosures and develop a robust, competitive assurance market without over regulating a nascent ecosystem. 

What is the register?

An interim, non‑legislative public register of sustainability assurance practitioners will launch by mid 2026, ahead of the 1 January 2027 reporting year. The Government has tasked the FRC to proceed now, with potential statutory underpinning to follow “when Parliamentary time allows”, but registration will remain voluntary. The interim register will initially verify practitioners’ skills and expertise and will evolve over time to embed quality characteristics. 

What is the scope of the voluntary oversight regime?

The scope is deliberately broad. Registered practitioners are intended to be recognised for assurance over the, in development, UK Sustainability Reporting Standards (UK SRS), TCFD aligned disclosures, the European ESRS and other standards aligned with the ISSB. The regime is profession agnostic and will prioritise registration of firms first, with individuals to be considered later. We expect registration conditions around skills, experience, quality management, ethics and independence, with strong support for use of ISSA (UK) 5000 as the benchmark assurance standard. 

What has the market reception been like?

Market reception has been broadly supportive. In theory, enhanced oversight and standardisation of assurance providers will help ensure that information investors and asset managers rely on for investment decisions is robust and trustworthy. In turn, investors, should have a greater degree of confidence in the quality and comparability of sustainability-related financial disclosures which managers and issuers disclose.

The voluntary start has been welcomed, however, some are concerned that a two tier market will emerge and lead to potential confusion between registration and assurance quality with associated cost consequences. 

In the longer term, if assurance over sustainability disclosures becomes mandatory the market can expect a more consistent baseline of assured information, further supporting effective capital allocation and risk management. However, in practice, this additional oversight could lead to increased costs of assurance providers. These costs are likely to be passed on in the form of an increase in the costs of their assurance services. 

Timing and next steps

The FRC plans to set up the non-legislative public register by mid-2026. In parallel, the FCA’s consultation on the UK SRS proposes updates to the UK Listing Rules to reference the incoming UK SRS and, critically, to require in‑scope listed issuers to state in their annual financial report whether they have obtained third‑party sustainability assurance over their UK SRS disclosures. This consultation was published in January 2026 and is intended to shape issuer reporting and market signaling ahead of the first UK SRS reporting years.