A potential strike by tax workers means that motor retailers subject to the self-assessment tax regime need to ensure that they complete their tax returns as soon as possible, warns the Retail Motor Industry Federation (RMIF).

The Public and Commercial Services Union (PCS), which represents around 70,000 staff in Her Majesty’s Revenue and Customs (HMRC), is voting on strike action over pay, office closures, job cuts and privatisation.

It could decide to order a walk-out shortly after the ballot is declared, on January 23, just over a week before the 31 January deadline for completed forms.

Any outstanding tax should also be paid before the deadline. If not, interest will be charged.

Those in the industry who could be affected include sole traders, those in partnerships, company directors, certain staff in receipt of benefits in kind and those who can claim tax relief on business expenses.

According to RMIF tax expert Louise Wallis, late returns could prove costly: “Those that do not get their returns in on time, strike or not, will be fined £100.”

“Returns can be completed online at www.hmrc.gov.uk which could be the best option considering the potential delays that the strike could cause if it goes ahead.”