Non Performing Assets:A non-performing asset (NPA) is a loan or advance for which the principal or interest payment remained overdue for a period of 90 days. Description: Banks are required to classify NPAs further into Substandard, Doubtful, and Loss assets. Substandard assets: Assets which has remained NPA for a period less than or equal to 12 months. Doubtful assets: An asset would be classified as doubtful if it has remained in the substandard category for a period of 12 months. Loss assets: As per RBI, œLoss asset is considered uncollectible and of such little value that its continuance as a bankable asset is not warranted, although there may be some salvage or recovery value. 