cash expenses

Sec 40A(3)(a) of the Income Tax Act, 1961 provides that any expenditure incurred in respect of which payment is made in a sum exceeding Rs. 10000/- in a single day otherwise than by account payee cheque drawn on a bank or by an account payee bank draft or through use of electronic clearing system, shall not be allowed as a deduction. 

Sec 40A(3)(b) also provides for deeming a payment as profits and gains of a business or profession if the expenditure is incurred in a particular year but the payment is made in any subsequent year in a sum exceeding Rs. 10000/- otherwise than by account payee cheque or by an account payee bank draft or through use of electronic clearing system.