Many contractors have been left with an undetermined or unexpected result regarding IR35 from the HM Revenue & Customs’ (HMRC) CEST (Check Employment Status for Tax) tool.

However, in light of recent data from HMRC, experts are calling on contractors to seek expert advice from a human to appeal unfair decision.

HMRC’s latest figures show that the indetermined rate of CEST is as high as 22 per cent, meaning that more than a fifth of the results provided do not deliver a status outcome for employers – leaving them with difficult decisions about a person’s IR35 status.

Chris Mattingly, CEO of IR35 Navigator, said: “The number of outcomes where the decision is undetermined continues to rise. This demonstrates that automated tools, such as CEST, cannot be relied upon to decide a worker’s employment status for tax.