For your operations to be regarded as business activities, they must involve transactions of an economic nature. What you do must have the potential of producing a profit. Business resulting in losses over the first few years is still considered business as long as the activities may generate a profit in the future.
The tax authorities will consider the period over which the activities are carried out as well as the extent of these activities when deciding whether it is a business or a hobby.
Note that the conditions are not absolute – there are no definite thresholds that must be exceeded for the hobby to be regarded as business. However, in one case (business) all costs related to the activities are deductible on your tax return, in the other (hobby) they are not. It is therefore very important that you engage in a dialogue with the tax authorities at an early stage to prevent any surprises later on.
One particular condition is related to sales of goods and/or services and value added tax (VAT). Your business shall not add VAT to your sales until the total sales of goods or services that are subject to VAT exceed NOK 50 000 over a period of 12 months.
It is important that the first invoice causing the limit to be exceeded includes VAT. Also, prior to the invoice, the business must be registered in the Value Added Tax Registration List.