Which amount shall be taken to calculate interest under Section 234B if the advance tax paid is less than 90% of the assessed tax?
Where the advance tax paid by the assessee is less than 90% of the assessed tax, the interest shall be charged on the amount of assessed tax less advance tax paid.

If tax is paid on the basis of self-assessment under Section 140A, interest will be calculated on the amount by which advance tax paid falls short of assessed tax up to the date of payment of self-assessment tax, after that interest will be calculated on the amount by which aggregate of advance tax and self-assessment tax paid under Section 140A falls short of the assessed tax.​