Cash payment disallowance rules restrict business deductions for large non-banking payments, subject to specified exceptions and relaxations. Disallowance applies to expenditure paid otherwise than through specified banking or online modes where the payment to a single person in a day exceeds the prescribed cash threshold, so that such expenditure is not allowed as a deduction in computing business income. Where an expense previously allowed as a deduction is later settled in cash beyond the prescribed threshold, the payment is deemed to be income of the subsequent year under the head Profits and gains of business or profession. The framework also preserves rule-based exceptions for designated payments, banking modes, agricultural produce, cottage-industry goods, employee benefits, salary in special posting situations, agent payments, and foreign-currency transactions.