Debit note or supplementary invoice with GST if amount charged was less :
Where a tax invoice has been issued for supply of any goods or services or both and the taxable value and/or tax charged in that tax invoice is found to be less than the taxable value and/or tax payable in respect of such supply, the taxable person, who has supplied such goods or services or both, shall issue to the recipient a debit note containing such particulars as may be prescribed – section 34(3) of CGST Act.
‘Debit Note’ shall include a supplementary invoice – Explanation to section 34(4) of CGST Act.
Declaration of debit note in the return of supplier – Any registered person who issues a debit note in relation to a supply of goods or services or both shall declare the details of such debit note in the return for the month during which such debit note has been issued and the tax liability shall be adjusted in such manner as may be prescribed- section 34(4) of CGST Act.