Corrective account (C4): introduction
Form C4 is a corrective account. Taxpayers or agents complete this form to tell us of amendments to the original account. Strictly speaking, they are required to deliver a corrective account (IHTM10805) within 6 months of discovering that the original account was incorrect. However, in certain circumstances (IHTM31023) the taxpayer or agent can save up the amendments and tell us about them in one go.
You only need to insist on the taxpayers completing a formal C4 in a few circumstances (IHTM10702).
In Scotland the C4(S) doubles as a Corrective Inventory to obtain an Eik to Confirmation.