AASB S2 Reporting Software for Group 2 and Group 3: Disclosure Figures Your Assurer Can Trace

Good AASB S2 reporting software gives you emissions figures your assurer can trace. Every Scope 1, 2 and 3 number in the climate statement should link to the document it came from. Each one should carry the method, the emission factor and the global warming potential set used to calculate it. The governance, strategy, risk and transition plan sections should sit in the same place as the figures, so one change flows through.

That is the test. Group 2 entities are already four months into their first reporting year, which began on 1 July 2026. Group 3 starts on 1 July 2027. Both face limited assurance under ASSA 5010 from year one.

So the choice between spreadsheets, a consultant-only approach and software comes down to one question. Which option produces a figure that survives an assurer pulling a sample?

What an assurer will ask for in year one

Limited assurance sounds light. In practice the assurer still picks a sample of disclosed numbers and asks where each one came from. They want the invoice or meter read, the quantity, the unit, the factor, the calculation and the person who approved it.

In a spreadsheet that trail lives in someone's head. The quantity was typed from a PDF, the factor was pasted from last year's workbook, and the GWP column was never labelled. We spent years running production data pipelines in Australian enterprise environments, and this is the most common failure we saw. The number was right. Nobody could prove it.

Reasonable assurance applies from periods starting 1 July 2030. At that level the assurer tests the whole chain. A trail that is hard to rebuild now can turn into a qualified opinion later.

There's also the sign-off. Directors declare the sustainability report under the Corporations Act. For the first three years the declaration covers whether the entity took reasonable steps to comply. A board can only say that with a straight face if the data has controls around it. Our guide to ASRS assurance requirements walks through what the assurer tests in more detail.

The 10-point checklist for choosing ASRS reporting software

We built this list from the AASB S2 text and from what ASSA 5010 engagements ask for. Use it in vendor demos. Ask each question with your own documents on screen, never a vendor's sample file.

#	What to check	The question to ask in a demo
1	Source traceability	Click a Scope 3 tonne. Can you open the invoice line it came from?
2	Physical quantities	Does it read physical quantities from supplier documents, or map dollars to a spend factor?
3	Data quality disclosure	Are spend-based figures flagged as low quality automatically?
4	Scope 2 both ways	Does it hold location-based and market-based Scope 2 side by side?
5	GWP and factor provenance	Is the GWP set and factor version stored on each record?
6	Boundary and consolidation	Can it consolidate a joint venture under operational control, financial control and equity share?
7	Period locking and restatement	Can you lock a period, and does a restatement demand a written reason?
8	Audit events	Is every ledger change logged with who, what and when?
9	Disclosure sections	Do governance, strategy, risk, scenario inputs and transition plan sit beside the metrics?
10	Assurer access	Can your assurer get read-only access and an evidence pack without a data dump?

Points 1 to 5 decide whether the numbers hold. Points 6 to 8 decide whether they stay put after sign-off. Points 9 and 10 decide how much rework the disclosure needs in the final six weeks.

Scope 3 figures that move when your purchasing changes

Scope 3 relief applies in your first reporting year. Most Group 2 entities will disclose Scope 3 from their second period. Use that year to build supplier data that holds up.

The hard part sits in the documents. A concrete docket says "N32". That is a strength grade, and it says nothing about carbon. Concrete gets ordered in cubic metres while the factor is per tonne. Reo arrives in lineal metres. A supply-and-install subcontract can put the same tonne in your inventory and your subcontractor's.

Spend-based estimates hide all of that. GHG Protocol ranks spend-based data at the bottom of its Scope 3 data hierarchy for good reason. Buy a lower-carbon concrete at the same price and a spend-based figure shows no change at all. The dollars didn't move, so the reported number doesn't either.

Carbonly reads supplier invoices, delivery dockets, utility bills, EPDs, waste and freight records in eight file formats, including scanned PDFs. It pulls the physical quantity from each line and keeps the verbatim line text as evidence. Five-tier material matching links each line to an Australian NGA factor, an EPD factor or your own factor library, with a confidence score.

A low-confidence match goes to a reviewer. So does a unit that can't be converted without a figure the document doesn't state, like cubic metres to tonnes with no density. When a reviewer corrects a match, the line text is saved as an alias for your organisation only. Lines that only have a dollar value are flagged low data quality, which is the disclosure AASB S2 expects you to make about your measurement approach.

That covers checklist points 1, 2 and 3.

Scope 1 and 2 with the method written on every row

Scope 1 and 2 have no first-year relief. They're also where the method choices pile up.

AASB S2 references AR6 global warming potentials. NGER uses AR5, set in regulation 2.02 of the NGER Regulations. AASB S2025-1 lets an NGER reporter keep AR5 for the NGER-covered portion of its AASB S2 figures. Confirm the application date and any early-application position for your first reporting period with your assurer.

Carbonly calculates on AR5 GWPs, with methane at 28. AR5 is the only GWP set it writes. If part of your footprint sits outside NGER coverage and needs AR6, that conversion is a step you or your adviser perform on top of the ledger. Our post on how AR5 and AR6 change the calculation has the full gas table and worked examples.

The platform records provenance instead. The emission factor version, the GWP set and the calculation method are snapshotted onto each record when it's confirmed. Change the factor library next year and last year's figures keep the values they were calculated on.

Scope 2 is held both ways. Location-based figures use state grid factors. The NGA Factors 2026 edition from DCCEEW applies to activity from 1 July 2026, with NSW and ACT at 0.60 kg CO2-e per kWh and Victoria at 0.74. Market-based figures sit alongside, so you can describe your contractual instruments with the numbers that support them. That covers points 4 and 5.

Boundaries, period locks and restatements

The figures need to stay put after the board signs.

Joint ventures are a common trap in construction and resources. Operational control and equity share can each give a different answer for the same project. Carbonly consolidates under operational control, financial control or equity share from one ledger and shows the unadjusted total beside the result. That puts the boundary choice in front of the assurer. Point 6.

Periods can be locked once reported. A restatement needs a recorded reason before it goes through, and every ledger write creates a typed audit event. Records are retained for seven years under internal policy, above the NGER Act's five. When last year's figure changes, you can show what moved and why. Variance explanation splits a change into activity, factor, source and method effects, which is the substance of a good restatement note. Points 7 and 8.

Deterministic anomaly checks run daily at 6am and after each document batch. They catch duplicates, outliers and unit mismatches using rules, which an assurer can read and test. A Data Health Agent reports coverage gaps and stale data, so a missing month of electricity bills shows up early in the year.

The disclosure sections and the parts software won't write

AASB S2 asks for more than metrics. It wants governance, strategy, risk management, scenario analysis and any transition plan, all consistent with the numbers.

Carbonly runs an AASB S2 disclosure workflow across governance, strategy, the climate risk register, scenario analysis inputs, the transition plan and metrics. It exports to PDF and Word. The metrics in the draft come from the same ledger the assurer samples, so a late correction flows through. Our post on what ships in the auto-generated AASB S2 document shows the output section by section.

For your assurer there's an Auditor Workspace with a read-only role, plus an evidence pack designed to support ASSA 5010 limited assurance. The pack bundles the source documents, matches and approvals behind the disclosed figures. Points 9 and 10.

There are limits. Software does not write your scenario narrative. It holds the inputs, but choosing scenarios, judging their financial effect and explaining resilience is analytical work. Software also doesn't make the materiality judgement about which climate risks and opportunities belong in the statement. Those calls belong to management, the board and, often, a consultant who has done this across many entities.

We think that split is right. If a consultant is leading your engagement, the software is their workshop equipment. Their hours go on the judgement, while the platform handles the dockets and last year's workbook.

We're less sure how far quantity-based Scope 3 can go in year two for an entity with hundreds of small suppliers. Some categories will stay estimates for a while. The Supplier Portal and the Supplier Data Chase Agent help, because suppliers submit data scoped per project and get followed up on a configured cadence. But a supplier who never replies still leaves a gap, and the honest move is to disclose it as an estimate.

Where Group 2 and Group 3 should start

Group 2 entities are mid-year. The priority is Scope 1 and 2 evidence for the current period and a working trail before the assurer arrives. Our Group 2 reporting requirements guide covers the timetable, and the CFO playbook for a first AASB S2 disclosure covers sign-off and budget.

Group 3 entities have until 1 July 2027. That is enough time to run software beside your current spreadsheet for a quarter and compare the two. Our Group 3 requirements guide sets out the thresholds and what to build first. For the wider buying decision, see how to choose carbon accounting software in Australia.

Pricing is a per-project licence plus an A$100 per month workspace minimum, with no per-seat fees. The full feature list is on the features page, and the AASB S2 topic hub collects everything we've written on the standard.

Pick three documents that gave your team trouble last quarter: a concrete docket, a multi-site electricity bill and a supplier invoice with a credit line. Bring them to a 30-minute walkthrough and watch each one become a traceable line, or email hello@carbonly.ai.

FAQ

Do Group 2 entities have to report Scope 3 in their first year? No. AASB S2 gives first-year relief for Scope 3, so most Group 2 entities disclose it from their second reporting period. The supplier data still takes about a year to build, so it is worth starting now.

Which global warming potentials does Carbonly use? Carbonly calculates on AR5 GWPs, the NGER basis, with methane at 28. AASB S2025-1 lets NGER reporters keep AR5 for the NGER-covered portion of their AASB S2 figures. Any portion that needs AR6 is converted outside the platform by you or your adviser.

Will software make my climate statement pass assurance? No software can promise that. The reporting entity and its assurer remain responsible for the outcome. Software can give the assurer a trail from each disclosed figure back to its source document, with the factor, method and approval recorded.

Can AASB S2 software write the scenario analysis? It can hold the inputs, such as scenarios chosen, assumptions and linked risks. It does not write the narrative or judge the financial effect. That analytical work sits with management, the board and any consultant leading the engagement.

When does reasonable assurance apply to AASB S2 disclosures? Reasonable assurance applies from periods starting 1 July 2030. Until then, limited assurance under ASSA 5010 applies from year one. As at November 2026, Treasury has consulted on options to change the assurance timeline, so check for updates before you plan.

How is Carbonly priced for ASRS reporting? Carbonly charges a per-project licence plus an A$100 per month workspace minimum. There are no per-seat fees, so finance, sustainability, your consultant and your assurer can all have access.