Your sustainability team is chasing emissions factors and supplier surveys. Meanwhile the harder question sits in your ledger: whose numbers are these, from which entities, reconciled how, signed off by whom? Under the Corporate Sustainability Reporting Directive (CSRD), that is a consolidation problem — and consolidation is finance's job.
Much of the CSRD conversation has been framed as a sustainability exercise. For a group, it is closer to a second consolidation cycle: many entities, one boundary, one assured statement. The office of the CFO already runs that machine for the financial statements. The sustainability statement now needs the same discipline.
Why is CSRD a consolidation problem, not a sustainability one?
Because the reporting happens at group level, over a defined perimeter of entities — exactly the problem finance solves every close. Under ESRS 1, a parent that prepares consolidated financial statements prepares its sustainability statement on a consolidated basis too, covering the parent and its subsidiaries. So the deliverable is not a single company's ESG data; it is the aggregation of many entities' data into one coherent statement. That is consolidation. The subject matter is emissions, workforce and governance rather than revenue and EBITDA, but the mechanics — collect from each entity, apply a consistent boundary, eliminate double-counting, roll up, reconcile, sign off — are the ones finance runs already.
Does the ESG reporting boundary really track the financial consolidation perimeter?
Yes — under ESRS 1 the sustainability statement is prepared for the same group as the consolidated financial statements. The boundary you consolidate for financially is, in substance, the boundary you report sustainability for. That is a gift to finance and a trap for everyone else: the perimeter is already defined, mapped and maintained in your consolidation system, so ESG reporting should inherit it rather than reinvent it in a spreadsheet. Get this wrong and the two statements describe different groups — an obvious problem once anyone assures them side by side. Who actually owns that boundary election, and its edge cases like joint ventures and newly acquired entities, is a question in its own right; we cover it in our sibling piece on who owns the CSRD reporting boundary.
What does "the same rigour as financial data" actually mean?
It means controls, an audit trail, and sign-off — because the sustainability statement is assured, not self-declared. CSRD requires assurance over the sustainability statement, which changes the standard an ESG number must meet. A figure that would embarrass no one in a voluntary report has to withstand an assurance provider asking for its source, its calculation, its controls and its owner. In practice that means a defined source system per data point; version control and an audit trail; intercompany-style consistency so the same metric is measured the same way in every entity; and a named person who signs off. Finance recognises all of this — it is how the numbers in the annual report are already governed. ESG data has typically not been held to it. Closing that gap is the work.
Can a subsidiary still be exempt from producing its own report?
Generally yes, where the parent produces a conforming consolidated sustainability report that covers it. Much like the financial-statements exemption, a subsidiary can usually be relieved of its own detailed sustainability reporting when it is captured within a compliant group report. That reinforces the point: the centre of gravity is the group statement, prepared once, over the consolidation perimeter, to an assured standard. It is another reason the data belongs in the group's consolidation machinery rather than scattered across local sustainability spreadsheets that no one has to reconcile.
One caveat on all of the above. CSRD is still moving. Under the 2026 "Omnibus" changes, the scope of who must report and the timing of when they must report have been scaled back, and the detail continues to shift. Treat any specific threshold or date as provisional and check the current position before you act — the direction of travel in this article (group-level, boundary-linked, assured) is the durable part; the precise perimeter of who is caught is not.
Where should ESG data actually live?
In — or directly alongside — the same consolidation system finance already runs, not in disconnected spreadsheets. If the ESG reporting boundary tracks the financial perimeter, and the data needs financial-grade controls, and the output is an assured group statement, then the logical home is the machinery already built for exactly that shape of problem. Disconnected spreadsheets fail on every count: no shared boundary, no audit trail, no consistent definitions, no reconciliation to the financial group. Putting ESG data into the consolidation layer gives you one perimeter, one set of controls, and one sign-off path for both financial and sustainability numbers. That is the finance-owned cut of CSRD: not a new reporting team, but an extension of the discipline you already have.
If you want to see where your finance function stands on this today, the Finance Value Score scores ESG reporting as one of its areas — treated exactly this way, as a finance-owned consolidation problem rather than a sustainability side-project. It is a free two-minute self-assessment that rolls up into one 0–100 score, with the gap to a mature, AI-embedded finance function costed in pounds.
Common questions
Is CSRD a finance or a sustainability responsibility?
Both functions contribute, but the parts that decide whether the statement holds up — the reporting boundary, entity-by-entity consolidation and data-level controls — are finance's home ground. The sustainability team owns much of the subject-matter expertise; finance owns the rigour that makes the numbers assurable.
Does the ESG reporting boundary match the financial consolidation perimeter?
Under ESRS 1, a parent that prepares consolidated financial statements prepares its sustainability statement on the same consolidated basis, covering the parent and its subsidiaries. In substance the ESG boundary therefore tracks the financial consolidation perimeter, so it should be inherited from your consolidation system rather than rebuilt separately.
Why does ESG data suddenly need financial-grade controls?
Because the sustainability statement under CSRD is subject to assurance, not left as self-declared narrative. Once a third party has to sign off, each figure needs a defined source, a calculation, an audit trail and an owner — the same standard finance already applies to the annual report.
Can a subsidiary avoid producing its own CSRD report?
Generally it can be exempt where the parent produces a conforming consolidated sustainability report that covers it, mirroring the familiar financial-statements exemption. This keeps the centre of gravity on one group statement, prepared over the consolidation perimeter to an assured standard.
Have the 2026 Omnibus changes removed the obligation?
No — but they have scaled back the scope of who must report and the timing of when, and the detail is still settling. Treat specific thresholds and dates as provisional and verify the current position; the group-level, boundary-linked, assured shape of the requirement is the part that is durable.