The error may be due to incorrect invoicing of amount or quantity, or the commodity may have defects or other impairment.
Erroneous invoicing may be corrected by the following actions, depending on what type of error it is meant to amend:
· A credit invoice is issued for the part that was faulty invoiced to begin with.
· The correction is made in the next invoice (to the customer) with a clear reference as to what has been corrected.
· A new invoice is issued, at the same time as a credit invoice is issued in order to reset the original invoice.
· An additional invoice is issued. May for instance occur if the delivered quantity was greater than originally invoiced.
Some new businesses must use an additional invoice at the time when the sales exceed the VAT eligibility limit. E.g. a commodity is sold and invoiced without VAT, causing the total sales to tip over the NOK 50 000, thus requiring registration of the business in the VAT Register, followed by an invoice of the additional VAT on the last sale.
The credit invoice must indicate clearly which original invoice it is referring to.