(a) 30th September of the assessment year, where the assessee, other than an assessee referred to in clause (aa), is -
(i) a company,
(ii) a person (other than a company) whose accounts are required to be audited under the Income-tax Act, 1961 or any other law in force; or
(iii) a working partner of a firm whose accounts are required to be audited under the Income-tax Act, 1961 or any other law for the time being in force.
(aa) 30th November of the assessment year, in the case of an assessee who is required to furnish a report referred to in section 92E.
(b) 31st July of the assessment year, in the case of any other assessee.
17 October 2013
For such corporate assessees which is required to furnish a report u/s 92E of the Income Tax Act, 1961 due date is 30.11.2013
For any other assessees Like Salaried Income ,Person having Income from House property ,Interest income , Business Income where accounts are not required to be audited due date is 31.07.2013..
18 October 2013
In addition to what Aryan suggested also for those company who are having specified domestic transaction needs to file Return of income along with Form 3CEB on 30.11.2013.