Mandatory reporting started for your customers, not for you. That's the trap.

On 1 July 2026, the second wave of Australia's mandatory climate-reporting regime switched on: companies in the next size band down now have to produce climate disclosures for financial years starting from that date, joining the largest companies who came under the rules eighteen months earlier.

If you run a business with 20–500 staff, you read that news (if you read it at all) and correctly concluded it doesn't apply to you. It doesn't. You will probably never file a climate disclosure in your life.

Here's the part that does apply to you.

Covered companies can't report without your numbers

The reporting standard requires covered companies to account for their supply chain: the emissions of the businesses they buy from. A supermarket, a major builder, a bank, a large logistics customer: if they're covered, their suppliers' emissions are part of their number.

They cannot invent those figures. So they ask their suppliers. The request arrives as a questionnaire, a supplier-portal form, a clause in the next contract renewal, or a line in a tender: provide your emissions data.

This is how an obligation that legally sits on a few thousand large companies reaches businesses that will never file a disclosure of their own. The regulation flows downhill, and it arrives without the compliance budget that was supposed to come with it.

Two things about the timing that most coverage gets wrong

The supply-chain part hasn't switched on yet. Companies in this second wave get first-year relief on supply-chain emissions. Their first disclosure that has to include your numbers covers financial years starting 1 July 2027, not 1 July 2026. So the purely regulatory reason for a covered customer to chase you is still about a year out.

And the Government may narrow the asking. In the 2026-27 Budget it committed to consult on clearer boundaries around what covered companies can demand from their suppliers, naming small business specifically. No consultation paper has been published yet, so nobody knows how far it goes.

We would rather tell you that than sell you a deadline. It does raise the obvious question, though: if the regulatory wave is a year out and might get trimmed, why would a supplier do anything now?

Because the requests arriving now aren't really about the regulation

The emissions questions actually landing on mid-sized Australian businesses today mostly come from somewhere other than the disclosure regime, and none of those sources are waiting for it:

Supermarket supplier programs. Both majors expect emissions engagement well below the multinational tier now, with science-based-target expectations carrying dates in the 2027 range. That is retailer purchasing policy, set by the retailer, and it does not move if Canberra changes its mind.

Government tenders. The Commonwealth's sustainable procurement rules already require emissions information on contracts above roughly $1m, with periodic reporting after award. That is a condition of bidding, today.

Corporate scorecards. EcoVadis, Sedex and the like are driven by multinational procurement teams answering to their own global frameworks. Australian disclosure rules are not the reason those forms arrive.

A certification that's closing. Climate Active ends on 30 June 2027, and every business that used it as its answer to this question needs a new one.

Tender templates that used to ask “do you have an environmental policy?” now ask for numbers, and customer scorecards that scored intentions now score evidence. We should be straight about the limits of what anyone knows here: there is no published survey of how many Australian suppliers have received these requests, so treat any vendor who quotes you a number on that (including us) with suspicion. What we can say is where the requests come from, and that those sources have their own timetables.

And almost every software vendor in the market has responded by chasing the covered companies, the ones with mandates and budgets, leaving the suppliers, who face the same questions without the mandate, to a consultant or a spreadsheet.

What a sensible response looks like

Not panic, and not a sustainability program. Three things, sized to the actual ask:

Know your number before you're asked. A baseline built from your electricity bills, fuel records and gas bills covers the bulk of what a mid-sized business is asked for. The data already exists in your accounts-payable folder.

Make it defensible, not impressive. The analyst reading your submission checks whether the method holds up: published factors, stated boundaries, working shown. A modest, well-evidenced number beats an ambitious estimate every time.

Own it in a form you can reuse. The same customer asks again next year. If your number lives in a consultant's model, next year costs what this year cost. If it lives in a system you keep, next year is an afternoon.