In VAT, the variation note (also known as a credit note or debit note) is an integrative invoice that is issued when, after the original invoice was issued or registered, there have been changes in how much turnover or registered.
The procedure for issuing a VAT change note must follow the same requirements as the issuance of an invoice; but has special rules for variations that occur within a year, and others without time limits.
The rules of are art. 26 of the VAT Decree (D.P. 26 October 1972, No. 633).
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