Almost half the businesses in a national survey said the carbon tax had little or no impact on their operations, with larger firms reporting the least effect, according to research over the past year by DBM Consultants.
The findings, from almost 18,000 respondents, come as the Rudd government weighs up cutting the carbon price by bringing forward the shift from a fixed price to a floating one sooner than July 1, 2015.
Of the firms surveyed, 45 per cent said the carbon price - which rose from $23 per tonne of carbon dioxide to $24.15 at the start of July - was negative for their business, with one in seven describing the impact as "very negative". DBM said 47 per cent said there was no effect.
The reported effects varied across industries, with the impact described as negative by 67 per cent of mining businesses and 59 per cent of manufacturers. By contrast, firms in education, finance, health and property reported negative impacts for between 31 per cent and 38 per cent of respondents.
"There is real polarisation - with very different results between the service industries and those which produce things or use a lot of energy, such as transport," said Tim Honcoop, account director at DBM.
Businesses with an annual turnover of $50 million tended to become less negative about the tax as the survey progressed. Those reporting a negative impact dropped to 33 per cent from 39 per cent.
The report contrasts with a survey released last month by the Australian Industry Group showing that - negative impact or not - most companies had not reduced the carbon intensity of their operations during the first year of the carbon tax.
Among the reasons for the limited response was that companies had already taken steps to improve energy efficiency after several years of rising gas and electricity prices. Some said they were too cash-strapped.
The Australian Industry Group survey also found some firms were not cutting emissions intensity because they expected the carbon price to fall - possibly to zero - raising doubts about the return on any investment in energy saving.
The Coalition has vowed to scrap the carbon tax, if elected, while the Rudd government is considering whether it can move to a floating price linked to the European emissions market - trading at less than $6 per tonne as of Thursday - sooner than mid-2015.