IHTM36167 | Investigating incorrect accounts, information or documents: deciding the amount of penalty due
From HM Revenue & Customs · Inheritance Tax Manual
For a penalty to be due on an incorrect account, information or document (IHTM36101) you need
If there is no evidence of fraud or negligence then no penalty is due in respect of delivering, furnishing or producing incorrect accounts, information or documents. But if there was a failure to correct an error without unreasonable delay (IHTM36208) then you will need to consider a penalty under IHTA84/S248.
Before negotiating a penalty (IHTM36221) with the taxpayer you will need to get prior approval (IHTM36223) from your manager for the amount of penalty (‘the expected offer’ (IHTM36174)) you are seeking.
Even if you decide not to take a penalty you should consider writing to or telephoning the taxpayer (IHTM36271) to explain what might be done in future when providing an account, information or document so that the question of penalties does not arise.