I have a client who I am fairly confident, given recent cases, will escape IR35 but who has nonetheless asked me to give him an estimate of the additional tax and NI payable if he is successfully challenged, which I have prepared. However I want to include in addition an estimate of the penalties that he would suffer if he were at a later date - perhaps three years given the time it typically takes HMRC to pick these up - to be successfully challenged. I know for instance that the PAYE penalties start to accrue very quickly: could someone very kindly help with what amounts I need to include?
Any help would be much appreciated.
Alan