Carry forward of loss only when return is filed in time u/s 139(3)

Section 139(3) If a person has sustained a loss under the head “Profits and gains of business or profession” or under the head “Capital Gains” and claims that such loss should be carried forward under section 72 or section 73 or section 74 or section 74A, then he may furnish a return of loss within the time prescribed under section 139(1) and all provisions of the Income-tax Act shall apply as if it were a return furnished under section 139(1).

Section 80 Notwithstanding anything contained in Chapter VI, the loss which has not been determined in pursuance of a return filed in accordance with the provisions of section 139(3), shall not be allowed to be carried forward and set-off under section 72 or section 73 or section 74 or section 74A.

Note 1 : If loss return is filed as per section 142(1) then loss cannot be carried forward.