A Regulatory Line Drawn in 2026
Singapore’s Accounting and Corporate Regulatory Authority has moved from aspiration to enforcement architecture. Under the climate reporting requirements confirmed in ACRA’s 25 August 2025 announcement and operationalised through 2026, Straits Times Index constituents must report Scope 3 greenhouse gas emissions from financial year 2026, while Scope 3 remains voluntary for non-STI listed companies until further notice. The distinction is not cosmetic. It creates a two-speed disclosure landscape in which the largest listed entities become the de facto data anchors for entire supply chains, while smaller listed firms watch and prepare.
Why Scope 3 Is the Hard Part
Scope 1 and Scope 2 reporting is now mandatory for all listed companies from FY2025. Those categories are relatively bounded: fuel burned on site, electricity purchased. Scope 3 stretches outward into purchased goods and services, upstream transport, business travel, and the use and end-of-life treatment of sold products. For a Singapore-listed manufacturer or retailer, the majority of emissions typically sit outside its own fence line. ACRA’s staggered approach acknowledges that supplier data infrastructure does not materialise overnight. The relief is not a retreat from transparency; it is a sequencing decision that places the heaviest data burden first on the companies with the greatest market weight and the most developed reporting capabilities.
The Large Non-Listed Company Horizon
The more consequential long-term signal lies beyond the STI. Large non-listed companies will face climate reporting obligations from financial years commencing on or after 1 January 2030. That five-year runway matters because many of these entities are privately held subsidiaries, family-controlled conglomerates, or regional headquarters operations whose procurement decisions cascade through the local economy. When a large non-listed property group or logistics operator begins disclosing Scope 3, its Singapore-based suppliers will face requests for emissions data whether or not those suppliers are themselves listed. Transparency travels downstream faster than regulation.
The Supplier Engagement Reality
For STI constituents preparing FY2026 reports, the operational question is no longer whether to report but how to obtain defensible numbers. Supplier questionnaires, spend-based estimates, and hybrid approaches are all in play, but assurance-readiness favours primary data where feasible. The Singapore Emission Factors Registry, expanded to 319 factors in January 2026, provides a national reference point for converting activity data into emissions estimates, covering all Scope 1 and Scope 2 categories and four of the fifteen Scope 3 categories. That still leaves eleven Scope 3 categories without full local factor coverage — a gap that will force companies to rely on international datasets, industry averages, or direct supplier measurement.
The Competitive Logic of Early Disclosure
ACRA’s framework is often framed as a compliance cost. A more useful lens is supply-chain positioning. Companies that establish credible Scope 3 baselines in FY2026 will be better placed to respond to customer decarbonisation requirements, access green financing, and defend market share as regional procurement standards tighten. The tiered mandate gives Singapore’s largest listed companies a first-mover advantage in building the supplier engagement machinery that will eventually become table stakes. The transparency era is not arriving uniformly; it is arriving first at the top, and it will flow downward.
