29 March 2017
You can file belated return u/s 139(4) for the FY 2015-16 i.e., AY 2016-17 on or before 31.03.2017 without any penalty. Return for AY 2016-17 can also be filed u/s 139(4) upto 31.03.2018 but subject to a maximum penalty of Rs 5000/- u/s 271F. So it is advisable to file the return on or before 31.03.2017.