The filing of income tax return is a legal obligation for every person whose total income during the previous year exceeds the maximum amount which is not chargeable to income tax under the provisions of the Income Tax Act, 1961. An individual is required to file his return of income by 31^st July of the assessment year. If an assessee after furnishing the return u/s 139(1) or in pursuance of a notice issued u/s 142(1) discovers any omission or any wrong statement therein, he may file a revised return within one year from the end of the relevant assessment year or before the assessment is made. For example, a person filing return for Assessment year (AY) 2009-10  can file return either up to 31/03/2011 or before the assessment is completed for AY 2009-10 , whichever events happens first. However, a revised return can be filed only if the original return has been filed within due date u/s 139(1) or in pursuance of a notice issued u/s 142(1).  Revised return is filed u/s 13(5) of the Income Tax Act, 1961. Even a loss return filed u/s 139(3) can be revised and loss as per the revised return can be carried forward.  Revise return can be filed online or physically. But you can file revised return online only and only if you have filed the original return online and have the 15 digit acknowledgement number. Income Tax Act does not prohibit filing online revised return against original physical return filed earlier. But when one try to file revised online return income tax department searches detail of original return filed which is not find and error is communicated as details of original return filed in hard copy yet to punch in department net work data. Accordingly, the assessee can file revised return online only if he had filed the original return online otherwise revise return is to be filed in hard copy. We at Taxmantra.com have the expertise in handling issues relating to individual taxation (Tax Returns + Tax Support+ Tax Planning). Taxmantra.com provides most hassle free tax return filing/ online return filing experience. Once you have collected, your salary certificate and other documents, we request you to please log in to www.taxmantra.com/ereturns or you can also directly mail at info@taxmantra.com to submit the details. Upon receiving the documents, we would contact you to file your return of income.