Which period shall be considered for interest under Section 234A if the return is not furnished in re-assessment?
​​Where return of income is required by a notice issued under Section 148 (Income escaping assessment), but it is not furnished, the interest shall be charged for the period commencing from the day immediately following the expiry of the time allowed under the notice and ending on the date of completion of re-assessment.

Interest shall be charged on the amount by which the tax determined under re-assessment exceeds the tax determined as per the completed assessment.​