Most finance departments aren't ready for FRS 101 and FRS 102 financial reporting standards that started in January.
Only a third of 500 finance departments surveyed by IRIS said that they complied with the new simpler rules for financial reporting for small and medium-sized companies and companies with consolidated accounts.
Around 27% of accountants questioned were unsure whether their business complied with the new rules.
In addition 43% said that the "bureaucracy of compliance" was the biggest issue facing finance departments.
Phill Robinson, chief executive of IRIS, said: "Considering the notice period that was given for these changes to GAAP to include FRS 101 and 102, we were surprised to find such a large number of corporate accountants still aren’t compliant.
"Although the repercussions of non-compliance can vary, failure to comply with the current financial reporting standards would be problematic for both the organisation and any accountancy firms acting on their behalf," he said.