IHTM10702 - Corrective account (C4): when is an account required (England, Wales and Northern Ireland)?

In strictness a C4 should be completed in all cases where there is an amendment to the account. But in most cases you can accept amendments that are notified in a letter or even in straightforward cases over the telephone. This applies even where the taxpayers make a voluntary disclosure of an omitted asset.

In general you should only ask for a C4 where

• a repayment is due and the taxpayers supporting evidence is slender so that the signatures of the accountable persons (IHTM10801) is thought desirable
• where there are numerous or complicated amendments, or
• additional tax is payable following the receipt of a Cap Form A 5C (IHTM05083)
• when property given an estimated value in a reduced account (IHTM10471) is redirected to a chargeable beneficiary (IHTM10478).

If you have to call for a corrective account you should consider raising provisional assessments or calling for a deposit if there are significant amounts of unpaid tax not in dispute.