If you give your customers credit, you should write the invoices as quickly as possible after delivery of the goods or services. It is important to collect your money without unnecessary delay

What should the invoice look like?

• Date of the issue of the documentation.
  
• Number that is assigned by the invoicing system or pre-printed.
  
• Name and address of the business selling the commodity or service.
  
• The business’ organisation (company) number followed by the letters “MVA” (VAT) if the business is registered in the VAT Register.
  
• Name and address or the organisation number of the business that receives the commodity or service. Note that the name and address of the buyer is not obligatory when selling for cash.
  
• A description of the commodity or service.
  
• The quantity or extent of the goods/services rendered.
  
• The price of the goods/services and when payment is due.
  
• The time and place of delivery.
  
• If applicable, VAT and other taxes.
  

Tax eligible and tax free sales, as well as sales exempted from VAT shall be listed separately and the total for each group calculated. The same rules apply when the sales consist of goods/services that have different VAT rates.

The invoice is issued in at least two copies, where one is kept by the selling company.

Erroneous invoices must be stored, but marked obliterated (in Norwegian "makulert"). Thus, the series of numbers on the invoices is kept intact, and one may easily find those that are not included in the accounting.

Using manual bookkeeping of the (output) invoices, one may choose not to register the erroneous ones. Using automatic transfer from the invoice part of the accounting software, the erroneous invoices must be credited internally.

Adding VAT

All businesses registered in the VAT Register must in principle add VAT to the output invoices, regardless of the recipients. The exceptions are for instance export, sales of second hand cars and work on public roads.

When to invoice?

Write the invoice as soon as possible after the goods/services are delivered, preferably in the very day of the delivery.

In the directives to the Bookkeeping Act, the deadlines for different types of invoices are regulated.

The act itself states that the invoice must be sent as soon as possible, and not later than one month after the delivery. The exceptions are:

VAT eligible businesses must invoice the same year as the delivery takes place.
Pre-invoicing is normally not allowed. However, there are exceptions for licences, rent and similar services. Such services may be pre-invoiced (and pre-paid) within the actual year.

Reminders

When an invoice is overdue, you should send a reminder immediately. Getting paid for services sold is one of the key factors determining if the business is a success or not. The rules for reminders (and legal recovery of the debts) are listed here.

Cost of credit time

Over the last few years there has been a significant increase in the number of legal recoveries of debts. One of the reasons is that the customers try to stretch the credit as far as possible – at the sellers' expenses. If, for instance, the business has an agreed overdraft costing 9% and the value of the credit sales is NOK 4 million, then a reduction of the credit time by 20 days will mean an extra income of NOK 20 000.