IHTM10252 - Certificates of tax deposit: calculating interest

Certificates of Tax Deposit (CTD) carry simple interest calculated on a daily basis from the date of deposit until the earliest of either:

• the date of payment of the tax which they are being used to pay
• the date on which they are surrendered for cash, or
• six years after the date the deposit was made.

Full details of how interest is paid on CTDs can be found on GOV.UK.

Where the certificate is purchased after the date that a tax liability became due, interest is not added to the deposit, but no further interest is charged on the equivalent amount of the tax liability.