Almost one in five of Australia's top 200 companies are providing very little reporting on their climate risks ahead of the implementation of mandatory disclosure.
The Australian Council of Superannuation Investors report released on Friday found the majority of ASX200 members have net-zero commitments and most have also set interim targets, which helps investors to gauge the credibility of a company's plans.
But gaps remain in the depth and scope of climate reporting, with some companies only partially reporting on their climate risks and 18 per cent doing almost nothing.
Researchers also considered the companies' integration of climate into financial statements, with less than a third (29 per cent) disclosing how climate change was considered when evaluating financial performance.
Many of these assessments remained qualitative, and moving from words to numbers would be necessary if investors were to understand the potential financial impact of climate change, the report found.
The big end of town will be the first to be covered by under proposed legislation slated to take effect on January 1 that puts climate reporting on par with traditional financials.
More than 6000 entities will be required to report under new climate-related disclosure requirements in the next few years, with critics concerned about the cost of more green tape for business.
The survey found large firms were better prepared with two-thirds of ASX200 companies having a net zero commitment, up eight per cent on a year ago.
That means 82 per cent of the market capitalisation of the companies, or $2.2 trillion, is invested in companies that have set net-zero ambitions.
"Mandatory climate reporting will provide investors with clearer information about Australian companies' exposure to climate risk," the industry body's CEO Louise Davidson said.
She said most companies had moved away from box-ticking reporting and were providing greater detail on how climate change considerations were being integrated into strategy and key business decisions.
"We have seen significant improvements in climate reporting in the last few years, but transitioning to a low-carbon future remains a huge challenge," Ms Davidson said.
"To meet it, company climate plans need to be credible and backed by science," she said.
Two-thirds or 132 companies undertook and disclosed analysis of physical risks from climate change, up 12 per cent on a year ago.
But the quality and depth of disclosure remains a challenge for investors, according to the report.
Some 33 companies recognised the need for a "just and equitable transition" for workers and communities impacted by change and a further 16 have committed to it or disclose targets to achieve a just transition - mostly in sectors such as energy and mining.
"While the issue of a transitioning workforce is less relevant to some companies, where it does pose a material risk, disclosures are still lacking," Ms Davidson said.