Time Limit for completion of Assessment u/s. 143 or 144 of the Income-tax Act, 1961: AY 2016-17 - withing 21 months from the end of Assessment Year i.e. 31.12.2018 AY 2017-18 - withing 21 months from the end of Assessment Year i.e. 31.12.2019 AY 2018-19 - withing 18 months from the end of Assessment Year i.e. 30.09.2020 AY 2019-20 - withing 12 months from the end of Assessment Year i.e. 31.03.2021 Period of Limitation Table under the Income-tax Act, 1961