IT Return for 2017-18

No, you can't but You can apply for Condonation of Delay in Filing ITR Section 119(2)(b) (if have refund or carry forward loss) within 6 years of from the end of the assessment year for which income tax return has to be filed or You may receive a notice from the Income Tax Department with penalty charges for not filing ITR. The alternatives and the risk for not filing the ITR vary from individual to individual depending on their tax due. You should pay off your income tax liability as soon as possible rather than waiting for the Income Tax Notice. 

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