Rob hyrons - Fotolia IR35 private sector reforms: HMRC reminds firms to use ‘reasonable care’ when applying new tax rules As the countdown to the IR35 reforms being rolled out to the private sector continues apace, HM Revenue and Customs issues compliance guidance for firms in-scope of the new rules Share this item with your network: By Published: 16 Feb 2021 9:40 HM Revenue and Customs (HMRC) has confirmed that ensuring private sector firms are taking “reasonable care” when determining how the contractors they engage with should be taxed will be part of its IR35 compliance activities post-April 2021. The organisation has published a guidance document, designed for use by the medium to large private sector firms in scope of the IR35 reforms, to set out the approach it will take to ensure compliance with the changes once they come into effect on 6 April 2021.