AASB S2 Climate Disclosure for Your Clients — We Do the Compliance, You Do the Assurance
Australia’s mandatory climate disclosure framework — the Treasury Laws Amendment (Financial Market Infrastructure and Other Measures) Act 2024 — requires large Australian entities to produce audited climate-related financial disclosures under AASB S2 and IFRS S2. For the first time, climate disclosures are subject to external assurance requirements enforced by the AUASB — creating a direct and growing revenue stream for accounting and audit firms.
Carbonhalo handles every element of the disclosure work: baseline emissions assessment, climate risk analysis, gap analysis, and the complete AASB S2 report. Your firm focuses on what you do best — delivering the limited assurance engagement, building the client relationship, and earning the assurance revenue.
In Partnership With
What AASB S2 Means for Your Accounting Firm
Australia’s mandatory climate disclosure regime creates two distinct and complementary obligations — one for large businesses (to prepare climate-related financial disclosures) and one for their accounting and audit providers (to provide external assurance on those disclosures).
The Assurance Requirement
Under AASB S2, large entities are required to obtain external assurance over their climate-related financial disclosures. The assurance obligations are phased in by group:
Reporting Group | First Report | Assurance Level (Year 1) | Assurance Level (Later Years) |
|---|---|---|---|
Group 1 |
FY2025 (lodged 2026) |
Limited assurance |
Reasonable assurance — phased in from FY2028 |
Group 2 |
FY2026 (lodged 2027) |
Limited assurance |
Reasonable assurance — phased in from FY2030 |
Group 3 |
FY2027 (lodged 2028) |
No assurance required (Years 1–3) |
Limited assurance from FY2031 |
Assurance is conducted under AUASB standards — specifically ASAE 3000 (Assurance Engagements Other than Audits or Reviews) and ASAE 3410 (Assurance Engagements on Greenhouse Gas Statements). These standards require the assurance provider to have access to the underlying data, calculation methodology, and working papers that support the climate disclosure.
What this means for your Accounting Firm
Every Group 1 and Group 2 entity that is also an audit client of your firm will require an AASB S2 limited assurance engagement. That engagement requires the assurance provider to review the climate disclosure against the AASB S2 standard, verify the emissions calculations, and assess the adequacy of the governance and risk management disclosures.
The challenge for most accounting firms is that this work requires specialised climate accounting knowledge — emissions factor databases, GHG Protocol methodology, scenario analysis frameworks — that falls outside a typical audit team’s existing competency. Firms that try to build this in-house face significant investment in training, software, and specialist hiring.
Carbonhalo’s partner program resolves this by handling all of the climate compliance work upstream — so your team receives a complete, audit-ready disclosure package that meets AUASB working paper standards. Your firm can deliver the assurance engagement using your existing audit capabilities, without needing to become a climate accounting specialist.
Why Accountants Should Care
Your clients will soon be required to report – many don’t know it yet!
Accounting firms are the trusted advisors to Australian businesses. As new climate reporting laws roll out, your role now includes identifying which clients meet legislative thresholds and ensuring they are prepared. Partnering with Carbonhalo helps you become that indispensable advisor.
Identify Client Needs
We help you identify clients impacted by AASB S2, giving you the leading edge by being proactive
Build Client Trust
Clients trust forward-thinking advisors. Demonstrate your expertise and avoid losing them to full-service firms
New Assurance Services
Businesses will require assurance to meet compliance — and your firm should be the one delivering it to your clients
How the Partnership Works
Other platforms require you to be a carbon accounting and legislative expert. Our process is designed so you focus on your core services – our experts handle the complexity and deliver simple solutions to you and your client.
Identify and Introduce
Review your client list using our threshold guide.
Introduce Carbonhalo where applicable.
We do the Compliance Work
Our experts complete all carbon accounting, climate disclosures and sustainability reporting, all delivered to you for assurance.
You Deliver the Audit or Assurance
You access our dedicated audit portal - undertake your assurance work - Bill the client
Grow Your Practice
Minimal effort for your firm. Maximum value to your clients.
Designed for Accountants and Advisors
Audit Ready Packs
Built to meet assurance standards. Making your audit process smooth and efficent.
We aren’t Competitors
We don’t offer audit or assurance services. No conflict, no competition for your core business.
Dedicated Audit Portal
Exclusive access to our secure portal for each of your clients. Clear view of data and methodologies.
Zero Climate Skills
Your team doesn’t need specalised climate expertise or skills. We handle the technical work.
Not Just Software
Not generic machine-generated garbage. Real experts combined with technology at every stage.
Affordable &
Flexible
Monthly pricing with
no lock in contracts or
annual price shock.
Does Your Client Need to Report?
Mandatory climate reporting is being phased in based on entity size, but awareness is low. Use these thresholds to identify which of your clients fall under the new legislation. Many businesses are still unaware of their obligations, giving you the perfect opportunity to provide proactive, valuable guidance.
Benefits for Accountants
New Billable Revenue
Your clients need assurance services to get compliant. Someone will earn that work — it should be your firm.
Zero Learning Required
We don’t make accountants learn carbon software — we do the work, you do the assurance.
Sticky Client Relationships
You become the proactive advisor protecting your clients from competitors and increasing long-term value
Frequently Asked Questions — AASB S2 and the Accounting Firm Partner Program
AASB S2 Obligations for Accounting Firms
Under AASB S2, entities subject to mandatory climate disclosure are required to obtain external assurance over their climate-related financial disclosures. Group 1 entities (FY2025) and Group 2 entities (FY2026) are required to obtain limited assurance from their first year of reporting. Assurance must be conducted by a registered company auditor under AUASB standards — specifically ASAE 3000 (Assurance Engagements Other than Audits or Reviews) and ASAE 3410 (Assurance Engagements on Greenhouse Gas Statements). Group 3 entities have no assurance requirement in their first three years, with limited assurance required from FY2031.
A client is required to report if it is an entity required to prepare financial reports under the Corporations Act 2001 and meets at least two of the three size thresholds for its reporting group: Group 1 (revenue >$500M, assets >$1B, or employees >500); Group 2 (revenue >$200M, assets >$500M, or employees >250); Group 3 (revenue >$50M, assets >$25M, or employees >100). The obligation applies to large proprietary companies, public companies, and registered managed investment schemes — not only ASX-listed entities. Carbonhalo provides a client threshold assessment tool for partner firms.
No — provided the assurance provider is not also the party that prepared the climate disclosure. APES 110 (Code of Ethics for Professional Accountants) prohibits a firm from providing both the preparation and assurance of the same disclosure. Carbonhalo’s partner program is specifically structured to preserve independence: Carbonhalo prepares the climate disclosure; your firm provides the assurance. The preparation / assurance split is structurally clean and consistent with APES 110 independence requirements. Your firm does not participate in the preparation of the disclosure at any stage.
Limited assurance engagements over AASB S2 climate-related financial disclosures are conducted under ASAE 3000 (Assurance Engagements Other than Audits or Reviews) and ASAE 3410 (Assurance Engagements on Greenhouse Gas Statements), both issued by the Auditing and Assurance Standards Board (AUASB). ASAE 3410 is specifically designed for GHG emissions data and covers the procedures required to verify emissions calculations, emission factors, organisational boundaries, and the completeness of the GHG inventory. Both standards require the assurance provider to have access to the underlying data, methodology documentation, and working papers that support the disclosure.
Not if your firm uses Carbonhalo as the compliance preparation partner. Carbonhalo provides a complete audit-ready working paper pack — including the full emissions inventory with source data, calculation methodology, emission factor references, scenario analysis documentation, and governance disclosure support materials — specifically structured for review by a competent auditor without climate expertise. Your team engages with the documented methodology and verifies the data against source materials using standard audit procedures. Carbonhalo’s technical team is available throughout the engagement to answer questions on emissions calculations and disclosure decisions.
About the Carbonhalo Partner Program
The program operates on a clean division of labour. Your firm identifies which clients meet the AASB S2 reporting thresholds using Carbonhalo’s client assessment tool, then makes an introduction to Carbonhalo. Carbonhalo scopes and prices the engagement directly with the client, manages the full compliance process — baseline emissions assessment, climate risk analysis, governance and strategy disclosures, and the complete AASB S2 report — and delivers the finished disclosure package to your firm through a secure, dedicated audit portal. Your firm then conducts the limited assurance engagement, issues the assurance report, and bills the client for the assurance work.
No. Carbonhalo is a climate disclosure preparation specialist only. We do not offer audit, assurance, or review services of any kind. We do not hold an Australian Financial Services Licence and we do not produce assurance opinions. The complete separation of preparation (Carbonhalo) and assurance (your firm) is fundamental to the program design and is consistent with APES 110 independence requirements. Your firm retains exclusive ownership of the assurance engagement and the client relationship.
The dedicated audit portal for each client engagement contains: the complete AASB S2 sustainability report and disclosures; the full GHG emissions inventory with Scope 1, 2, and 3 data, source data references, emission factor citations, and calculation methodology documentation; scenario analysis working papers; governance and risk management disclosure documentation; and all supporting materials required for a limited assurance engagement under ASAE 3000 and ASAE 3410. The portal provides full version history, audit trail, and access controls. Your assurance team accesses the portal directly — no data is transferred via email or unsecured channels.
There is no cost to accounting firms to join or operate as a Carbonhalo partner. Carbonhalo charges clients directly for the climate compliance work on a fixed monthly basis with no lock-in contracts. The accounting firm earns its revenue from the assurance engagement, which it bills to the client independently. Carbonhalo does not take any share of the accounting firm’s assurance fees.
For a first-time Group 1 reporter, the typical timeframe from Carbonhalo’s engagement with the client to delivery of the audit-ready disclosure package is 10–16 weeks. This covers the data collection phase (4–6 weeks), baseline emissions assessment and climate risk analysis (3–4 weeks), governance and strategy documentation (3–4 weeks), and report preparation and internal review (2–3 weeks). Group 2 entities with June 2027 deadlines can be engaged from early 2026 on a standard timeline. An accelerated pathway is available for Group 1 clients with urgent current-year deadlines.
Client Eligibility and Threshold Questions
Yes, if they meet two of the three size thresholds for their reporting group and are required to prepare financial reports under the Corporations Act 2001. The mandatory reporting obligation applies to large proprietary companies, not only to publicly listed entities. This is a common misconception among clients and their advisors — many large private businesses have not yet identified that they are captured. Group 2 and Group 3 large proprietary companies represent a significant, largely unaddressed advisory opportunity for accounting firms.
Non-compliance with mandatory climate disclosure obligations can result in civil penalties under the Corporations Act 2001. ASIC is responsible for enforcement and has signalled active oversight of the quality and completeness of disclosures, particularly for Group 1 entities. Directors of entities that fail to lodge required disclosures may face personal liability. ASIC has indicated it will apply proportionate enforcement in the early transition years, with a focus on good-faith compliance rather than technical perfection — but this does not remove the legal obligation to report. Accounting firms that have identified an affected client but not alerted them to their obligations also face potential professional and reputational exposure.
Become a Carbonhalo Partner
- Join other advisory firms generate more revenue
- Grow your practice
- Build closer client relationships
- See how we make the process simple
Your information is secure and will never be shared.