Tax Deduction at Source on interest on securities requires deduction when credited or paid, subject to specified exemptions. The person responsible for paying interest on securities must deduct tax at source at the time of credit to the payee's account or at payment, whichever is earlier, where the amount or aggregate during the financial year exceeds the prescribed threshold, at rates in force. The section specifies exemptions for various bonds, government securities and certain recipients subject to conditions such as written declarations, account-payee cheque payment or holding limits. Crediting interest to any account in the payer's books is deemed credit to the payee for triggering deduction.