Sustainability adjustments creep higher in reporting amongst UK’s largest companies

Sustainability adjustments creep higher in reporting amongst UK’s largest companies

• Almost half (46) of the FTSE 100 made restatements on their sustainability metrics in 2025, for the second year running;
• Of these total restatements, 77% related to greenhouse gas metrics, with the remainder (23%) comprised of a variety of non-GHG topics;
• 25 (or 60%) of the entities that reported a prior year adjustment (PYA) in 2024, did so again this year.

Almost half (46) of FTSE 100 companies made material prior-year adjustments (PYAs) to their climate and sustainability metrics for the second year running according to Deloitte UK. While the total number of companies making adjustments remained unchanged, analysis showed that six more companies made multiple adjustments this year, resulting in a total of 69 individual adjustments.

The latest analysis looked at climate and sustainability disclosures in the most recently published annual and/or sustainability reports as of 31 December 2024. Notably, 25 (60%) of the entities that reported a PYA last year (year end 31 December 2023), did so again this year.

Steve Farrell, partner and head of sustainability assurance at Deloitte UK, said: “Our analysis shows that these adjustments are now a regular feature of FTSE 100 climate reporting. Whilst the number of companies with material adjustments is the same as last year, this remains a significantly high amount, with continued challenges in getting sustainability reporting right. However, some of these companies have adjusted due to data improvements – that’s a real positive – showing reporters are focusing on better quality reporting.”

Of the restatements made, 77% related to greenhouse gas (GHG) emissions metrics, with the remainder (23%) comprised of a variety of other sustainability topics (including waste, water, diversity & inclusion, and health & safety). In comparison, last year 89% related to GHG emissions.

Farrell added: “This is reflective of the continued focus on improving reported GHG information, whilst at the same time, companies are considering the quality of a broader set of key sustainability information outside of GHGs.”

This year, the most frequent reason for a PYA was a change in method (35%), compared to 44% of PYAs reported in 2024. Adjusting for errors in historical reporting was slightly less common in this data set with 26% relating to correction of errors, compared to 29% of PYAs last year.

Emily Hesketh, sustainability assurance partner at Deloitte UK, said: “There are many challenges when it comes to sustainability reporting, and sustainability restatements are likely to continue for the foreseeable future. Caution is needed by the users of the information – including regulators, investors, and customers – when relying on the reported data to understand the progress companies are making to meet their targets.”

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