One dataset, many regimes

Picture a manufacturing group headquartered in Germany, with a UK listing, an Australian subsidiary and US sales above a billion dollars. In 2027 and 2028 it could be reporting under the ESRS, the UK Sustainability Reporting Standards, the Australian Sustainability Reporting Standards and California's SB 253, while also answering CDP and customer questionnaires.

Treat each of those as a separate project and you will run four materiality exercises, four data collections and four sign-off processes. Treat them as outputs of one system and most of the work is shared.

The common core

The climate requirements are where the overlap is greatest. ESRS E1, IFRS S2, UK SRS S2 and AASB S2 all build on the TCFD structure of governance, strategy, risk management, and metrics and targets. All of them use the GHG Protocol for Scope 1, 2 and 3 emissions. SB 253 asks for the same emissions numbers. A well-built greenhouse gas inventory serves all five.

Where they differ

• Materiality: the ESRS use double materiality; the ISSB-based regimes use financial materiality.
• Scope and boundaries: legal entity versus group, and how joint ventures and associates are treated.
• Timing and relief: each regime has its own first year, Scope 3 relief and assurance path.
• Extra topics: the ESRS go much wider than climate.

A practical architecture

1. One materiality process, two lenses. Assess impacts and financial effects together. The financial lens feeds ISSB-based reports; both feed the ESRS.
2. One inventory, tagged. Store each datapoint once, with tags showing which frameworks use it, and with its boundary, method and owner.
3. One control framework. Assurance providers will test the same numbers. Design controls once, at the level of the data, not the report.
4. Many outputs. Generate each report from the same dataset, adding the framework-specific narrative at the end.

Start with the gaps that hurt

The most common problem is not the frameworks. It is Scope 3 data quality, inconsistent boundaries between finance and sustainability teams, and no clear owner for each number. Fix those, and adding a new regime becomes a mapping exercise, not a new project.

Educational content, not legal advice.