Held, that the late payment surcharge was the additional amount levied on the customers for default in the payment of the electricity bill by the due date. It was levied to motivate the customers to pay the electricity bill on time. It was levied in the next billing cycle when the customer defaulted in earlier bill payment. However, it was recognised in the books of account on a collection basis. The assessee-company consistently recognised late payment of surcharge as and when it was recovered from the consumer, due to the uncertainty attached to its collection/recoverability. This was in tune with Accounting Standard 9 revenue recognition issued by the Institute of Chartered Accountants of India.  Addition  is deleted. (AY.2011-12, 2012-13)