With the implementation of Real Time Information (RTI) imminent, the Forum of Private Business (FPB) has warned that it is "last chance saloon time" for companies to prepare for the switch.
The new PAYE tax system requires all enterprises with employees to report earnings every month in real time rather than at the end of the tax year. It is set to be introduced on April 6th and by this date businesses will need to have new payroll software installed to handle the change.
A survey carried out by the organisation this week revealed that 18 per cent of firms still say they are unprepared for RTI. A further 21 per cent said it was not relevant to them and 60 per cent said they were ready.
HM Revenue and Customs (HMRC) has told Britain's business owners that it will be lenient in the initial introductory stages of RTI, ensuring firms that make mistakes will not be severely punished.
Nonetheless, companies that have not organised themselves ahead of April 6th may find themselves in difficult with HMRC.
"It's quite clear that there are businesses out there still not ready even at this late stage. The message we would like to get out there now, even at this point, is that it's still not too late to get on board for RTI – the ship has not sailed," said the group's head of policy, Alex Jackman.
"We know it can seem a daunting prospect to small firms, but it's just not an option to do nothing. Better to act now than have a phone call from an unhappy tax man after April 6th, and that could happen."
Rachel Andrews, payroll specialist at the FPB, offered last minute advice to businesses, suggesting they ensure they have everything they need ready ahead of the date. This includes employee addresses, their dates of birth and national insurance numbers, for example.
"The date of birth is more important now than previously, it has to be correct," she said.
"And the correct NI number is also crucial. If any business is unsure to the number's authenticity, they must submit an NI validation check with HMRC, and they will come back to you."