Yes, this step is mandatory – return-filing won’t be considered complete until you verify the returns. You have to complete this process within 120 days of having filed your ITR. But many forget to do so even though the electronic process can be completed through simple modes such as Aadhaar-OTP or net banking in a matter of minutes. You can also download the ITR-V, or acknowledgement form, and send it physically to the income tax department’s CPC office in Bengaluru.